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C语言是面向过程的,函数+结构体组成,C++是在C语言的基础上增加面向对象的能力,兼容C语言但是C语言不兼容C++,是Android中NDK开发的主要语言,对于学习NDK开发而言重要性是不言而喻的,接下来总结C++的学习,欢迎一起学习和交流~


打印日志

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void print() {
// c的打印方式
printf("c++ 语言的学习!\n");
// c++的打印方式,endl == \n
cout << "c++ 语言的学习!" << endl;
}

交换两个数

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// c的交换方式
void numberChange(int *num1, int *num2){
int temp;
temp = *num1;
*num1 = *num2;
*num2 = temp;
}
// c++的交换方式
void numberChange2(int &number1,int &number2){
// 内存地址与外部一致
cout << "n1内存地址:" << &number1 << ", n2内存地址:" << &number2 <<endl;

int temp;
temp = number1;
number1 = number2;
number2 = temp;
}
int main(){
int num1 = 10;
int num2 = 20;
// numberChange(&num1, &num2);
// cout << "n1:" << num1 << ", n2:" << num2 << endl;
cout << "n1内存地址:" << &num1 << ", n2内存地址:" << &num2<<endl;
numberChange2(num1, num2);
cout << "n1:" << num1 << ", n2:" << num2 << endl;
return 0;
}

通过内存地址修改某个值

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int n1 = 999;
int n2 = n1;
// n1 n2内存地址不同
cout << &n1 << "---" << &n2 << endl;

int n3 = 999;
int &n4 = n3;
// n3 n4内存地址相同
cout << &n3 << "---" << &n4 << endl;
n4 = 777;
// n3 n4都改为777
cout << n3 << "---" << n4 << endl;

定义结构体

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typedef struct {
char name[20];
int age;
}Student;
int main(){
Student student = {"小明", 30};
return 0;
}

函数重载

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int add(int number1,int number2 ){
return number1 + number2;
}

int add(int number1,int number2,int number3){
return number1 + number2 + number3;
}

// 支持默认形参,直接重载1-4个参数方法
//int add(int number1 = 1,int number2 = 2,int number3 = 3, int number4 = 4){
// return number1 + number2;
//}

类的定义

  • Teacher.h中声明
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    #include <iostream>
    using namespace std;
    class Person{
    private:
    char *name;
    int age;
    public:
    Person(char * name, int age):name(name){
    this -> age = age;
    cout << "Person 构造函数" << endl;
    }
    void print(){
    cout << this -> name << "," << this -> age << endl;
    }
    };

    // 默认私有继承,子类中可以访问父类的成员,类外不行
    // 公开继承,子类在类外也可以访问父类的成员 class Student:public Person
    class Student: Person{
    private:
    char * course;
    Student(char * name, int age, char * course): Person(name, age),course(course){
    cout << "Student 构造函数" << endl;
    }
    public:
    void test(){
    print();
    }
    // 构造函数顺序:Person,Student,析构函数顺序Student,Person
    ~Student(){
    cout << "Student 析构函数" << endl;
    }
    };
    class Teacher{
    private:
    char *name;
    int age;
    public:
    void setAge(int age);
    void setName(char *name);
    int getAge();
    char* getName();
    // 静态变量声明再实现
    static int id;
    // 友元函数可以访问/修改所有私有成员
    friend void updateAge(Teacher *teacher, int age);
    };
  • Teacher.cpp中定义
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    #include "Teacher.h"
    #include <string.h>
    using namespace std;

    public:
    int Teacher::id = 9
    // 不需要::
    void updateAge(Teacher *teacher, int age){
    teacher -> age = age;
    }
    void Teacher::setAge(int age){
    this->age = age;
    }
    void Teacher::setName(char *name){
    this -> name = name;
    }
    int Teacher::getAge(){
    return this -> age;
    }
    char* Teacher::getName(){
    return this -> name;
    }
    // 先调两个参数的构造函数,再调用一个参数的构造函数
    Teacher(char *name):Teacher(name, 87){
    this.name = name;
    }
    // 拷贝构造函数,被const修饰只能写在类中访问私有成员
    Teacher(const Teacher &teacher){
    this -> age = teacher.age;
    // 浅拷贝
    // this -> name = teacher.name;
    // 如果存在堆成员采用深拷贝
    this -> name = (char *)malloc(sizeof(char*) * 10);
    strcpy(this -> name, teacher.name);
    }
    Teacher(char *name, int age){
    // 堆区创建的name
    this -> name = (char *)malloc(sizeof(char*) * 10);
    strcpy(this -> name, name);
    this.age = age;
    }
    ~Teacher(){
    // 释放堆区创建的属性
    if (this -> name){
    free(this -> name);
    this -> name = NULL;
    }
    }


    int main(){
    // 栈空间分配内存
    Teacher teacher;
    teacher.setAge(99);
    teacher.setName("李华");
    cout << "name:" << teacher.getName() << ", age:" << teacher.getAge() << endl;

    // free 不会调析构函数,malloc不会调构造函数
    // 堆空间分配内存
    Teacher *teacher2 = new Teacher(); //堆区 手动释放
    teacher2 ->setAge(88);
    teacher2 ->setName("李华成");
    // 堆空间的内存需要手动释放
    if (teacher2){
    delete teacher2; // 析构函数一定执行
    teacher2 = NULL;
    }

    Teacher teacher1("张三",34); //栈区 弹栈自动释放
    // 不会调用拷贝构造函数
    // Teacher teacher2;
    // teacher2 = teacher1;
    Teacher teacher2 = teacher1; // 调拷贝构造函数
    Teacher *teacher1 = new Teacher("李四",35);
    Teacher *teacher2 = teacher1; // 不会调拷贝构造函数
    int number = 9;
    int number2 = 8;
    // 常量指针
    const int *numberP1 = &number;
    *numberP1 = 100; // 不允许修改常量指针存放地址对应的值
    numberP1 = &number2; // 允许修改常量指针存放的地址
    // 指针常量
    int* const numberP2 = &number;
    *numberP2 = 100; // 允许修改指针常量存放地址对应的值
    numberP2 = &number2; // 不允许修改指针常量存放的地址
    // 常量指针常量
    const int* const numberP3 = &number;
    *numberP3 = 100; // 不允许修改常量指针常量存放地址对应的值
    numberP3 = &number2; // 不允许修改常量指针常量存放的地址
    return 0;
    }

    自定义命名空间

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    namespace MyNameSpace1{
    namespace MyNameSpace2{
    namespace MyNameSpace3{
    void out(){
    cout << "" << endl;
    }
    }
    }
    }
    int main(){
    // 第一种调用方式
    using namespace MyNameSpace1::MyNameSpace2::MyNameSpace3;
    out();
    // 第二种调用方式
    // MyNameSpace1::MyNameSpace2::MyNameSpace3::out();
    return 0;
    }

    可变参数

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    #include <stdarg.h> // 支持可变参数
    using namespace std;
    void sum(int count, ...){
    va_list vp; // 可变参数的动作
    // count 内部需要一个存储地址参考值,否则无法处理存放参数的信息,也用于循环遍历
    va_start(vp, count);
    int number = va_arg(vp, int);
    cout << number << endl;

    number = va_arg(vp, int);
    cout << number << endl;

    number = va_arg(vp, int);
    cout << number << endl;

    va_end(vp);
    }

    int main(){
    sum(54,6,7,8)
    return 0;
    }

    友元类

  • java反射的实现原理 native层利用友元类访问私有成员
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    # include<iostream>
    using namespace std;

    class ImageView{
    private int viewSize;
    friend class Class; // 声明Class为友元类
    };
    class Class{
    public ImageView imageView;
    void changeViewSize(int size){
    imageView.viewSize = size;
    }
    int getViewSize(){
    return imageView.viewSize
    }
    };

    int main(){
    Class imageViewClass;
    imageViewClass.changeViewSize(600);
    return 0;
    }

    运算符重载

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    class Position{
    private:
    int x, y;
    public:
    Position(int x, int y):x(x), y(y) {}
    void setX(int x){
    this -> x = x;
    }
    void setY(int y){
    this -> y = y;
    }
    int getX(){
    return this -> x;
    }
    int getY(){
    return this -> y;
    }

    // 如果没有&会创建副本,影响性能
    Position operator + (Position &position) {
    int x = this -> x + position.x; // 类里可以访问私有成员
    int y = this -> y + position.y;
    return Position(x, y);
    }

    void operator ++(){ //++对象
    this -> x = this -> x + 1;
    this -> y = this -> y + 1;
    }

    void operator ++ (int) { //对象++
    this -> x = this -> x + 1;
    this -> y = this -> y + 1;
    }

    friend void operator << (ostream &_START, Position position){
    _START << position.x << "," << position.y << endl;
    }

    friend ostream & operator >> (ostream &_START, Position position){
    _START << position.x << "," << position.y << endl;
    return _START; // 可多次打印
    }

    friend istream & operator >> (istream &_START, Position position){
    _START >> position.x;
    _START >> position.y;
    return _START; // 可多次打印
    }
    };

    class ArrayClass {
    private:
    int size = 0;
    int *arrayValue;
    public:
    void set(int index, int value){
    arrayValue[index] = value;
    size += 1;
    }
    int getSize(){
    return this -> size;
    }
    int operator[](int index){
    return this -> arrayValue[index];
    }
    void printfArrayClass(ArrayClass arrayClass){
    for (int i = 0; i < arrayClass.getSize(); ++i){
    cout << arrayClass[i] << endl;
    }
    }
    };


    int main(){
    Position position1(100, 200);
    Position position2(200, 300);
    Position res = position1 + position2;
    cout << res.getX() << "," << res.getY() << endl;
    Position pos(1, 2);
    pos ++;
    ++ pos;
    cout << pos.getX() << "," << pos.getY() << endl;
    cout >> position2 >> position2 >> position2;
    Position position;
    cin >> position;
    cout << position.getX() << "," << position.getY() << endl;

    ArrayClass arrayClass;
    arrayClass.set(0, 1000);
    arrayClass.set(1, 2000);
    arrayClass.set(2, 3000);
    printfArrayClass(arrayClass);
    return 0;
    }

    多继承

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    #include <iostream>
    using namespace std;
    class BaseActivity1{
    public:
    void onCreate(){
    cout << "BaseActivity1 onCreate" << endl;
    }
    void onStart(){
    cout << "BaseActivity1 onStart" << endl;
    }
    };
    class BaseActivity2{
    public:
    void onCreate(){
    cout << "BaseActivity2 onCreate" << endl;
    }
    void onStart(){
    cout << "BaseActivity2 onStart" << endl;
    }
    };
    class BaseActivity3{
    public:
    void onCreate(){
    cout << "BaseActivity3 onCreate" << endl;
    }
    void onStart(){
    cout << "BaseActivity3 onStart" << endl;
    }
    };
    class MainActivity1: public BaseActivity1,BaseActivity2,BaseActivity3{
    void onCreate(){
    cout << "MainActivity1 onCreate" << endl;
    }

    };
    int main(){
    MainActivity1 mainActivity1;
    mainActivity1.onCreate();
    // mainActivity1.onStart(); 有歧义,不知道调哪个父类的onStart,子类重写onStart就没问题
    mainActivity1.BaseActivity1::onStart();
    mainActivity1.BaseActivity2::onStart();
    mainActivity1.BaseActivity3::onStart();

    return 0;
    }

    class Object{
    public:
    int number;
    };

    // 虚继承解决歧义问题
    class BaseActivity1:virtual public Object{

    };

    // 虚继承解决歧义问题,原理是把多个变量化成一份
    class BaseActivity2:virtual public Object{

    };

    class Son :public BaseActivity1,public BaseActivity2{
    public:
    int number; // 覆盖父类number
    }
    int main(){
    Son son;
    son.BaseActivity1::number = 1;
    son.BaseActivity2::number = 1;
    son.number = 1;
    return 0;
    }

    多态

  • 重写和重载
  • 同一个方法有不同的实现,父类指向子类
  • 动态多态:程序在运行期间才确定调用哪个类的函数
  • C++默认关闭多态,在父类上给方法增加virtual关键字开启多态
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    #include <iostream>
    using namespace std;
    class BaseActivity{
    public:
    virtual void onStart(){
    cout << "BaseActivity onStart" << endl;
    }
    };
    class HomeActivity: public BaseActivity{
    public:
    void onStart(){
    cout << "HomeActivity onStart" << endl;
    }
    };
    class LoginActivity: public BaseActivity{
    public:
    void onStart(){
    cout << "LoginActivity onStart" << endl;
    }
    };
    void startToActivity(BaseActivity *baseActivity){
    baseActivity -> onStart();
    }

    void add(int number1, int number2){
    cout << number1 + number2 << endl;
    }

    void add(float number1, float number2){
    cout << number1 + number2 << endl;
    }

    void add(double number1, double number2){
    cout << number1 + number2 << endl;
    }
    int main(){
    BaseActivity *homeActivity = new HomeActivity();
    BaseActivity *loginActivity = new LoginActivity();
    startToActivity(homeActivity);
    startToActivity(loginActivity);
    if (homeActivity && loginActivity) delete homeActivity; delete loginActivity;

    add(100, 100);
    add(1.1f, 2.1f);
    add(23.2, 21.2);
    cout << endl;
    }

    纯虚函数

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    #include <iostream>
    using namespace std;
    class BaseActivity{
    private:
    void setContentView(String layoutId){
    cout << "解析布局文件,反射" << endl;
    }
    public :
    void onCreate(){
    setContentView(getLayoutId());
    initView();
    initData();
    initListener();
    }
    //纯虚函数就是抽象函数,必须实现,虚函数virtual String getLayoutId();不是必须实现的
    virtual String getLayoutId() = 0;
    virtual void initView() = 0;
    virtual void initData() = 0;
    virtual void initListener() = 0;
    };
    // 如果子类没有实现纯虚函数就是抽象类,不能实例化
    class MainActivity: public BaseActivity{
    String getLayoutId(){
    return "R.layout.activity_main";
    }
    void initView(){

    }
    void initData(){

    }
    void initListener(){

    }
    };
    int main(){
    MainActivity mainActivity;
    return 0;
    }

    全纯虚函数

  • C++没有接口,所有的函数都是纯虚函数就是C++的接口
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    #include<iostream>
    using namespace std;
    Class Student{
    int _id;
    string name;
    int age;
    };
    // 定义接口
    class Student_DB{
    virtual void insertStudent(Student student) = 0;
    virtual void deleteStudent(int id) = 0;
    virtual void updateStudent(int id, Student student) = 0;
    virtual void queryStudent(Student student) = 0;
    }
    // 接口的实现类
    class Student_DBImpl: public Student_DB{
    public:
    void insertStudent(Student student){

    }
    void deleteStudent(int id){

    }
    void updateStudent(int id, Student student){

    }
    Student queryStudent(Student student){

    }
    }
    int main(){
    Student_DBImpl student_DBImpl;

    return 0;
    }

    回调

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    // 返回的数据对象
    class SuccessBean {
    public:
    String username;
    String userpwd;
    SuccessBean(String username, String userpwd):username(username),userpwd(userpwd){}
    }
    // 回调接口
    class ILoginResponse{
    public:
    virtual void loginSuccess(int code, string message, SuccessBean successBean) = 0;
    virtual void loginError(int code, string message) = 0;
    }
    // 登录操作
    void loginAction(String name, String pwd, ILoginResponse loginResponse){
    if (name.empty() || pwd.empty()){
    cout << "用户名或密码为空" << endl;
    return;
    }
    if ("admin" == name && "123" == pwd){
    loginResponse.loginSuccess(200, "登录成功", SuccessBean(name, "恭喜你成功登入"));
    loginResponse.loginError(404, "用户名或密码错误");
    }
    }
    // 接口的实现类
    class ILoginResponseImpl: public ILoginResponse{
    public:
    void loginSuccess(int code, string message, SuccessBean successBean){
    cout << "登录成功" << "code:" << code << "message" << message << "successBean" << successBean.username << "," << successBean.userpwd << endl;
    }
    void loginError(int code, string message){
    cout << "登录失败" << "code:" << code << "message" << endl;
    }
    }
    int main(){
    string username;
    cout << "请输入用户名.." << endl;
    cin >> username;
    string userpwd;
    cout << "请输入密码.." << endl;
    cin >> userpwd;
    ILoginResponseImpl iLoginResponseImpl;
    loginAction(username, userpwd, iLoginResponseImpl);
    return 0;
    }

    泛型

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    template <typename TT>
    void addAction(TT n1, TT n2){
    cout << "模版函数:" << n1 + n2 << endl;
    }

    int main(){
    addAction(1, 2);
    addAction(10.2f, 20.3f);
    addAction(545.34, 324.3);
    return 0;
    }


随着工作年限的增长,越来越意识到C语言的重要性,Android的底层是C和linux内核,Android中为提高安全性,防止反编译,防止二次打包,提升程序的执行效率都是用C去实现的,作为Android开发者,掌握C语言才能进行NDK开发,提高自己的核心竞争力,拓宽职业道路


指针与地址

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int main(){
int i = 100;
double d = 200;
printf("i的值是:%d\n", i); // 100
printf("d的值是:%lf\n", d); // 200

printf("i的值是:%d\n", *(&i)); // 100 取该地址的值
printf("d的值是:%lf\n", *(&d)); // 200 取该地址的值

int *intP = &i;
double *doubleP = &d;

*intP = 220; // 修改内存地址对应的值为220
printf("i的值是:%d\n", *intP); // 220 取该地址的值
printf("d的值是:%lf\n", *doubleP); // 200 取该地址的值
}

交换两个变量

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void change(int *a, int *b){
int temp = *a;
*a = *b;
*b = temp;
}
int main(){
int a = 100;
int b = 200;
printf("a的值为:%d\n", a); // 100
printf("b的值为:%d\n", b); // 200

change(&a, &b);

printf("a的值为:%d\n", a); // 200
printf("b的值为:%d\n", b); // 100
return 0;
}

多级指针

  • 指针变量存放的是内存地址,指针变量自己也有地址
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    // 多级指针
    void test1(){
    int num = 999;
    int * p1 = &num;
    int ** p2 = &p1;
    int *** p3 = &p2;
    printf("p1的值是:%p, p2的值是:%p, p3的值是:%p\n", p1, p2, p3);// p1存放num内存地址,p2存放p1内存地址,p3存放p2内存地址
    printf("p1的值是:%p, p2的值是:%p, p3的值是:%p\n", &p1, &p2, &p3);// p1,p2,p3自己的内存地址都不一样
    printf("p2的内存地址对应的值是:%d\n",**p2); // 999
    printf("p3的内存地址对应的值是:%d\n",***p3); // 999
    }

    数组指针

  • 指针变量在32位下占4个字节,64位下占8个字节,指针类型决定了sizeof,获取元素时的偏移
  • 数组变量就是一个指针,存放的是第一个元素的内存地址,也等于它自己的内存地址
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    // 数组指针
    void test2(){
    int arr[] = {1,2,3,4};
    int *arr_p = arr;
    int i = 0;
    for (i = 0; i < sizeof arr / sizeof(int); ++i){
    printf("下标为%d的值是%d\n", i,*(arr_p + i));
    printf("下标%d的内存地址是%p\n",i, arr_p + i); // 地址间隔4个字节
    }
    // 同一个地址
    printf("arr = %p\n", arr);
    printf("&arr = %p\n", &arr);
    printf("&arr[0] = %p\n", &arr[0]);

    // 取数组第二个值
    arr_p ++;
    printf("%d\n", *arr_p);

    // 超出范围,野指针
    arr_p += 200;
    printf("%d\n", *arr_p);
    }

    内存静态开辟和动态开辟

  • 动态开辟需要手动释放,手动释放后如果不赋值为NULL,就是悬空指针
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    void dynamicAction(int num){
    // 堆区动态开辟1M内存
    int *arr = malloc(num * sizeof(int));
    printf("dynamicAction函数,arr自己的内存地址:%p,堆区开辟的内存地址:%p\n",&arr,arr);
    // dynamicAction函数,arr自己的内存地址:0x7ffee47e1480,堆区开辟的内存地址:0x7fdb5dd00000
    // 释放堆区开辟的内存
    if(arr){
    free(arr);
    arr = NULL; // 如果不赋值为NULL,就是悬空指针
    printf("dynamicAction函数2,arr自己的内存地址:%p,堆区开辟的内存地址:%p\n",&arr,arr);
    // dynamicAction函数2,arr自己的内存地址:0x7ffee47e1480,堆区开辟的内存地址:0x0
    }
    }
  • 静态开辟,使用栈内存,自动释放
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    void staticAction(){
    int arr[6];
    printf("staticAction函数,arr自己的内存地址:%p,堆区开辟的内存地址:%p\n",&arr,arr);
    }

    realloc重新开辟内存

  • 扩容内存时,地址不一定连续,物理内存被其它占用会返回新的地址,所以内存重新开辟时需要传入指针和总大小进行拷贝
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    int main(){
    int num;
    printf("请输入新的个数:");
    // 获取用户输入的值
    scanf("%d", &num);

    int *arr = (int *)malloc(arr, sizeof(int) * num);
    for (int i = 0; i < num; ++i){
    arr[i] = i + 10001;
    }
    printf("开辟的内存地址:%p\n", arr);
    // 开辟新的内存空间
    int newNum;
    printf("请输入新增加的个数");
    scanf("%d", &newNum);
    int *newArr = (int *)realloc(arr, sizeof(int) * (num + newNum));
    if (newArr){
    int j = num;
    for (;j < (num + newNum); ++j){
    arr[j] = j + 10001;
    }
    printf("新开辟的内存地址:%p\n", newArr);
    }
    // 释放内存操作
    if (newArr){
    free(newArr);
    newArr = NULL;
    arr = NULL;
    }
    else{
    free(arr);
    arr = NULL;
    }
    return 0;
    }

    函数指针

  • 使用函数指针实现回调,相当于Java的接口
  • 函数指针和它自己的内存地址相同
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    void add(int num1, int num2){
    printf("num1 + num2 = %d\n", (num1 + num2));
    }

    void mins(int num1, int num2){
    printf("num1 - num2 = %d\n", (num1 - num2));
    }

    // 传递函数指针
    void operate(void(*method) (int,int),int num1, int num2){
    method(num1,num2);
    }

    void test4(){
    operate(add, 10, 20);
    void(*method)(int,int) = mins;
    operate(method, 100, 20);
    // 函数指针和它自己的内存地址相同
    printf("%p, %p\n", add, &add);
    }

    生成随机数

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    #include <stdlib.h>
    #include <time.h>
    void test5(){
    srand((unsigned) time(NULL));
    int i;
    for (i = 0; i < 10; ++i) {
    printf("随机数%d\n", rand() % 100);
    }
    }

    复制字符串

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    #include <string.h>
    void test6(){
    char string[10];
    char* str1 = "abcdefghi";
    strcpy(string, str1);
    printf("%s\n", string);
    }

    字符串获取长度

  • 也可以直接使用strLen
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    void getLen(int *resultLen, char *str){
    int count = 0;
    while(*str){
    str ++;
    count ++;
    }
    *resultLen = count;
    }
    /**
    * C/C++会把数组优化成指针提高效率,导致长度计算错误
    int getLen(int arr[]){
    int len = sizeof(arr) / sizeof(int);
    return len;
    }
    */
    void test7{
    char str1[] = {'H','e','l','l','o','\0'}; // 遇到\0停下来
    str1[2] = 'z'; // 栈空间,允许修改
    printf("第一种方式:%s\n", str1);
    int count;
    getLen(&count, str1);
    printf("长度为:%d\n", count);
    char *str2 = "Hello"; // 结尾隐式增加\0
    // str2[2] = 'z'; 会报错,不允许修改全局区的字符串
    printf("第二种方式:%s\n", str2);
    }

    字符串转换

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    void convertInt(){
    char *num = "1";
    int res = atoi(num);
    printf("转换结果:%d\n", res);
    }

    void convertDouble(){
    double resD = atof(num);
    printf("转换结果:%lf\n", resD);
    }

    字符串比较

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    void test8(){
    char *str1 = "Hello";
    char *str2 = "hello";
    // int res = strcmp(str1, str2); // 区分大小写
    int res = strcmpi(str1, str2); // 不区分大小写
    if (!res){
    printf("相等");
    }else{
    printf("不相等")
    }
    }

    字符串查找子串

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    void test9(){
    char *text = "hello world";
    char *subtext = "w";
    // 从搜索到子串的下标位置截取到末尾
    char *pop = strstr(text, subtext);
    if (pop){
    printf("查找到了,pop的值是%s\n",pop);
    }
    else{
    printf("没有查找到,subtext的值是%s\n",subtext);
    }
    int index = pop - text;
    printf("%s第一次出现的位置是:%d\n",subtext, index);
    }

    字符串拼接

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    void test10(){
    char destination[25];
    char *blank = "--到--", *CPP = "C++", *Java = "Java";
    strcpy(destination, CPP); // 先拷贝到数组
    strcat(destination, blank); // 拼接blank
    strcat(destination, Java); // 拼接Java
    printf("拼接后的结果%s\n", destination);
    }

    字符串截取

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    void substring1(char *res, char *str, int start, int end){
    char *temp = str;
    int index = 0; // 当前截取的位置
    while(*temp){
    if (index > start && index < end){
    *res = *temp;
    res ++;
    }
    temp ++;
    index ++;
    }
    }
    void substring2(char **res, char *str, int start, int end){
    char *temp = str;
    char resArr[end - start]; // 方案1. 临时变量在栈中分配内存,方法结束会被释放
    // char *resArr = malloc(end - start); // 方案2. 堆中开辟内存
    int index = 0;
    for (int i = start, i < end; ++i){
    resArr[index] = *(temp + i);
    index ++;
    }
    // 二级指针的一级指针等于test11的res一级指针
    // *res = resArr; // 方案2. 结果指向堆中的数组,方法结束后也不能释放所以不推荐
    strcpy(*res, resArr); // 方案1. 拷贝到数组
    printf("截取后的结果:%s\n", resArr);
    }
    void substring3(char *res, char *str, int start, int end){
    for (int i = start; i < end; ++i){
    *(result++) = *(str + i);
    }
    }
    void substring4(char *res, char *str, int start, int end){
    strncpy(result, str + start, end - start);
    }
    void test11(){
    char *str = "hello";
    char *res;
    substring1(res, str, 1, 4);
    // substring2(&res, str, 1, 4);
    printf("截取后的内容是:%s",res);
    }

    大小写转换

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    void lower(char *dest, char *text){
    int *temp = text;
    while(*temp){
    *dest = tolower(*temp);
    temp ++;
    dest ++;
    }
    *dest = '\0'; // 结尾增加\0避免打出系统值
    printf("name:%s\n", text);
    }
    void test12(){
    char *text = "hello";
    char dest[20];
    lower(dest, text);
    printf("小写转换后的结构是:%s\n", dest);
    }

    结构体

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    struct Dog{
    char name[10];
    int age;
    char sex;
    }
    struct Person{
    char *name;
    int age;
    char sex;
    } person1 = {"小明", 21, 'M'}
    struct Study{
    char *studyContent;
    }
    struct Student{
    char name[10];
    int age;
    char sex;
    struct Study study; // 引用外部结构体,声明结构体对象
    // 定义结构体并声明结构体对象
    struct Wan {
    char *wanContent;
    }wan;
    }
    // 匿名结构体定义别名
    typedef struct {
    char *name;
    int age;
    char sex;
    } Cat;
    int main(){
    struct Dog dog;
    strcpy(dog.name, "旺财");
    dog.age = 2;
    dog.sex = 'M';
    printf("name:%s, age:%d, sex:%c \n", dog.name, dog.age, dog.sex);

    struct Student student = {"小红", 18, 'F', {"学习C"}, {"王者荣耀"}};
    printf("name:%s, age:%d, sex:%c, study:%s, wan:%s \n", student.name, student.age, student.sex, student.study.studyContent, student.wan.wanContent);

    struct Dog dog2 = {"旺财2"4, 'M'};
    struct Dog *dogp = &dog2;
    dogp -> age = 3;
    dogp -> sex = 'F';
    strcpy(dogp->name, "旺财3");
    printf("name:%s, age:%d, sex:%c \n", dogp->name, dogp->age, dogp->sex);
    free(dogp);
    dogp = NULL;

    struct Dog dogArr[10] = {
    {"旺财4"4, 'M'},
    {"旺财5"5, 'M'},
    {"旺财6"6, 'M'},
    {},
    {},
    {},
    {},
    {},
    {},
    {}
    };
    struct Dog dog9 = {"旺财9"9, 'M'};
    // dogArr[9] = dog9;
    *(dogArr + 9) = dog9;
    printf("name:%s, age:%d, sex:%c \n", dog9.name, dog9.age, dog9.sex
    // 动态申请内存
    struct Dog *dogArr2 = malloc(sizeof(struct Dog) * 10);
    strcpy(dogArr2->name, "大黄1");
    dogArr2 -> age = 2;
    dogArr2 -> sex = 'M';
    printf("name:%s, age:%d, sex:%c \n", dogArr2->name, dogArr2->age, dogArr2->sex);
    // 指针移到第8个元素
    dogArr2 += 7;
    strcpy(dogArr2 -> name, "大黄8");
    dogArr2 -> age = 3;
    dogArr2 -> sex = 'M';
    printf("name:%s, age:%d, sex:%c \n", dogArr2->name, dogArr2->age, dogArr2->sex);
    free(dogArr2);
    dogArr2 = NULL;

    Cat *cat = malloc(sizeof(Cat)); // 结构体指针
    return 0;
    }

    枚举

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    enum CommentType{
    TEXT = 10,
    TEXT_IMAGE,
    IMAGE
    };
    typedef enum {
    TEXT1 = 10,
    TEXT_IMAGE1,
    IMAGE1
    } CommentType1;
    int main(){
    enum CommentType commentType = TEXT;
    printf("%d\n", commentType);

    CommentType1 commentType1 = TEXT1;
    printf("%d\n", commentType1);
    return 0;
    }

    文件读写

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    void readFile(){
    char *fileName = "/Users/JessieKate/CLionProjects/TestProject/test.txt";
    FILE *file = fopen(fileName,"r"); // 此文件必须存在
    if (!file){
    printf("文件打开失败,请查看路径");
    exit(0);
    }

    char buffer[10]; // 创建buffer读取
    while(fgets(buffer, 10, file)){
    printf("%s", buffer);
    }
    // 关闭文件
    fclose(file);
    }

    void writeFile(){
    char *fileName = "/Users/JessieKate/CLionProjects/TestProject/test1.txt";
    FILE *file = fopen(fileName, "w"); // 此文件可以不存在
    if (!file){
    printf("文件打开失败,请查看路径");
    exit(0);
    }
    fputs("这是我写入的测试内容", file);
    fclose(file);
    }

    文件复制

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    void copyFile(){
    char *fileName = "/Users/JessieKate/CLionProjects/TestProject/test.txt";
    char *fileNameCopy = "/Users/JessieKate/CLionProjects/TestProject/testCopy.txt";
    FILE *file = fopen(fileName, "rb");
    FILE *fileCopy = fopen(fileNameCopy, "wb");
    if (!file || !fileCopy){
    printf("文件打开失败,请查看路径");
    exit(0);
    }
    int buffer[514]; // 缓存数组
    int len; // 每次读取的长度

    // fread 读入缓存buffer, 偏移数量, 读取字节数写入缓存
    while((len = fread(buffer, 1, 514, file)) > 0){
    fwrite(buffer, len, 1, fileCopy);
    }

    fclose(file);
    fclose(fileCopy);
    }

    文件大小

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    void getSize(){
    char *fileName = "/Users/JessieKate/CLionProjects/TestProject/test.txt";
    FILE *file = fopen(fileName,"r");
    if (!file){
    printf("文件打开失败,请查看路径");
    exit(0);
    }
    fseek(file, 0, SEEK_END); //从0开始挪动到文件结束
    long fileSize = ftell(file); //读取file的信息
    printf("%s文件的字节大小是:%ld",fileName, fileSize);
    }

    文件加密解密

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    void encrypt(){
    char * fileName = "/Users/JessieKate/CLionProjects/TestProject/Image.jpg";
    char * fileNameEncode = "/Users/JessieKate/CLionProjects/TestProject/Image_encode.jpg";
    FILE * file = fopen(fileName, "rb");
    FILE * fileEncode = fopen(fileNameEncode,"wb");

    if (!file || !fileEncode){
    printf("文件打开失败,请查看路径");
    exit(0);
    }
    char *password = "123456";
    // 加密,破坏文件,解密,还原文件
    int c;
    int index = 0;
    int pass_len = strlen(password); // 获取密码的长度

    // fgetc 返回EOF = end of file
    while((c = fgetc(file)) != EOF){
    // 循环获取密码的每个字符,1,2,3,4,5,6,1,2,3...
    char item = password[index % pass_len];
    printf("item:%c%\n",item);
    fputc( c ^ item, fileEncode);
    index++;
    }
    fclose(file);
    fclose(fileEncode);
    }

    void decrypt(){
    char * fileNameEncode = "/Users/JessieKate/CLionProjects/TestProject/Image_encode.jpg";
    char * fileNameDecode = "/Users/JessieKate/CLionProjects/TestProject/Image_decode.jpg";
    FILE * file = fopen(fileNameEncode, "rb");
    FILE * fileDecode = fopen(fileNameDecode,"wb");
    if (!file || !fileDecode){
    printf("文件打开失败,请查看路径");
    exit(0);
    }
    char *password = "123456";
    int c;
    int index = 0;
    int pass_len = strlen(password);

    // fgetc 返回EOF = end of file
    while((c = fgetc(file)) != EOF){
    char item = password[index % pass_len];
    fputc( c ^ item, fileDecode);
    index++;
    }
    fclose(file);
    fclose(fileDecode);
    }


最近入了一台pixel3当测试机和备用机,完美刷入最新的Android系统11,据说12这样刷入也是可以的,magisk刷root权限和电信模块,确实是最佳测试机,完整的google套件,原汁原味的Android系统,喜欢尝鲜,喜欢原生系统且有梯子的小伙伴可以考虑入手一台,它不会让你失望的。下面记录一下我的刷机流程,第一次刷pixel还是踩了不少的坑


Pixel3不支持中国电信,需要手机root后刷入电信模块才可以使用电信卡(包括打电话和流量上网),Root方案选择了magisk,兼容性好

刷入完整的官方Rom包

  1. 根据自己的手机型号和刷入的系统版本,下载对应的镜像文件,google官方Rom包地址:https://developers.google.com/android/images
  2. 打开开发者模式,狂戳Setting -> Build number,打开USB调试,Setting -> System -> Developer Options打开Usb debugging,勾选oem unlocking
  3. 配置adb命令,如果不是Android开发者可下载android-platform-tools,这里就不赘述了
  4. 解压下载的blueline-rq2a.210505.002-factory-687d8468.zip,有个flash-all.sh的脚本
  5. 手机进入fastboot模式,adb reboot bootloader,再执行这个脚本./flash-all.sh

安装Magisk并Root

github下载最新Magisk并安装到手机,https://github.com/topjohnwu/Magisk/releases

提取boot.img

刚下载的blueline-rq2a.210505.002-factory-687d8468.zip文件解压后内部仍有一个压缩文件image-blueline-rq2a.210505.002.zip,继续解压,解压后的文件夹中会得到一个boot.img,把它push到手机

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adb push ./blueline-rq2a.210505.002/image-blueline-rq2a.210505.002/boot.img sdcard/Download

Magisk修改boot.img

打开magisk选择第一个install,选择select and patch a file选择刚才push的文件boot.img,执行后会在该目录下生成一个magisk_patched.img,把这个文件pull到PC
adb pull /sdcard/Download/magisk_patched-23000_J2eHI.img

magisk_patched.img刷入手机

  1. 手机进入fastboot模式,adb reboot bootloader
  2. fastboot解锁,fastboot flashing unlock
  3. 刷入magisk_patched.img,fastboot flash boot magisk_patched-23000_J2eHI.img
  4. 重启手机,fastboot reboot

    验证是否root

    执行命令adb shell
    执行命令su
    查看pixel是否有确认root授权的提示

刷入电信模块

  1. github下载china_telecom_supporter,https://github.com/apporc/china_telecom_supporter
  2. 把压缩包push到手机上
    adb push ./china_telecom_supporter.zip /sdcard/Download
  3. adb命令解压
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    unzip -d /sdcard/Download/china_telecom_supporter /sdcard/Download/china_telecom_supporter.zip
  4. 移动解压后的文件夹到系统目录/data/adb/modules/
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    mv /sdcard/Download/china_telecom_supporter /data/adb/modules/china_telecom_supporter
  5. 删除 fdr_check 文件
    rm /data/vendor/modem_fdr/fdr_check
  6. 重启,如果刷入成功此时进入系统可以看到电信的信号了,能正常打电话和流量上网~


又是一段时间没有更新博客了,这段时间对以前的学习做了一个总结,还是很值得的,希望接下来的时间里,能继续保持学习的热情,稳定输出学习和工作的总结到博客,毕竟一个好习惯值得坚持下去~也希望和各位大佬一起学习和交流,接下来记录用kotlin手写PhotoView的过程


自定义View

  1. 居中位置绘制bitmap
  2. 计算小图,大图缩放比
  3. fling,双击,滑动时调整画布偏移值绘制
  4. 双击,缩放手势调整画布当前缩放比例绘制
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class PhotoView @JvmOverloads constructor(
context: Context, attrs: AttributeSet? = null, defStyleAttr: Int = 0
) : View(context, attrs, defStyleAttr) {
lateinit var bitmap: Bitmap
lateinit var paint: Paint
/**
* 原始位置
*/
var originalOffsetX = 0f
var originalOffsetY = 0f
/**
* 滑动偏移
*/
var offsetX = 0f
var offsetY = 0f
var smallScale = 0f // 小图缩放比
var bigScale = 0f // 大图缩放比
var currentScale = 0f // 当前缩放比
get() {
Log.i(TAG, "get: $field")
return field
}
set(value) {
field = value
invalidate()
Log.i(TAG, "set: $value")
}
var isLarge = false // 是否放大状态
lateinit var gestureDetector: GestureDetector // 手势回调
lateinit var scaleGestureDetector: ScaleGestureDetector // 缩放手势回调
val overScroller by lazy { OverScroller(context) } // 滚动工具类,边界回弹
// 缩放动画
val scaleAnimation: ObjectAnimator by lazy {
val temp = ObjectAnimator.ofFloat(this, "currentScale", 0f)
temp.setFloatValues(smallScale, bigScale)
temp
}

companion object {
const val SCALE_FACTOR = 1.5f
}

fun initBitmap(bitmap: Bitmap) {
if (width == 0 || height == 0) {
throw IllegalStateException("call after View is rendered")
}
this.bitmap = bitmap
paint = Paint(Paint.ANTI_ALIAS_FLAG)
gestureDetector = GestureDetector(context, PhotoGesture())
scaleGestureDetector = ScaleGestureDetector(context, PhotoScaleGestureListener())
// bitmap居中渲染
originalOffsetX = (width - bitmap.width) / 2f
originalOffsetY = (height - bitmap.height) / 2f
// 横图计算缩放比
if (bitmap.width.toFloat() / bitmap.height > width.toFloat() / height) {
smallScale = width.toFloat() / bitmap.width.toFloat()
bigScale = (height.toFloat() / bitmap.height.toFloat()) * SCALE_FACTOR
}
// 竖图计算缩放比
else {
smallScale = height.toFloat() / bitmap.height.toFloat()
bigScale = (width.toFloat() / bitmap.width.toFloat()) * SCALE_FACTOR
}
// 当前缩放为最小缩放
currentScale = smallScale
invalidate()
}

// 边界修正
private fun fixOffset(){
offsetX = min(offsetX,(bitmap.width * bigScale - width)/ 2)
offsetX = max(offsetX, -(bitmap.width * bigScale - width) / 2)
offsetY = min(offsetY, (bitmap.height * bigScale - height) / 2)
offsetY = max(offsetY, -(bitmap.height * bigScale - height) / 2)
}

override fun onDraw(canvas: Canvas?) {
if (this::bitmap.isInitialized) {
// 当前缩放占比
val scaleFaction = (currentScale - smallScale) / (bigScale - smallScale)
// 画布平移
canvas?.translate(offsetX * scaleFaction, offsetY * scaleFaction)
// 画布缩放
canvas?.scale(currentScale, currentScale, (width / 2).toFloat(), (height / 2).toFloat())
canvas?.drawBitmap(bitmap, originalOffsetX, originalOffsetY, paint)
}
}

override fun onTouchEvent(event: MotionEvent?): Boolean {
// 默认缩放回调处理
var res = scaleGestureDetector.onTouchEvent(event)
// 不是缩放操作时,由手势回调处理
if (!scaleGestureDetector.isInProgress) {
res = gestureDetector.onTouchEvent(event)
}
return res
}

// 滑动处理
val runnable = object :Runnable{
override fun run() {
if (overScroller.computeScrollOffset()){
offsetX = overScroller.currX.toFloat()
offsetY = overScroller.currY.toFloat()
invalidate()
postOnAnimation(this)
}
}
}

inner class PhotoGesture : GestureDetector.SimpleOnGestureListener() {

override fun onDown(e: MotionEvent?): Boolean {
return true // 拦截DOWN事件
}

override fun onFling(e1: MotionEvent?, e2: MotionEvent?, velocityX: Float, velocityY: Float): Boolean {
// 当前放大状态,调overScroller的fling
if (isLarge) {
overScroller.fling(offsetX.toInt(), offsetY.toInt(), velocityX.toInt(), velocityY.toInt(),
(-(bitmap.width * bigScale - width) / 2).toInt(),
((bitmap.width * bigScale - width) / 2).toInt(),
(-(bitmap.height * bigScale - height) / 2).toInt(),
((bitmap.height * bigScale - height) / 2).toInt(),
300,300)
// 滑动刷新偏移值处理
postOnAnimation(runnable)
}
return super.onFling(e1, e2, velocityX, velocityY)
}

override fun onDoubleTap(e: MotionEvent?): Boolean {
isLarge = !isLarge
// 当前是放大状态
if (isLarge) {
// 刷新绘制位置
e?.let {
offsetX = (it.x - width / 2f) - (it.x - width / 2f) * bigScale / smallScale
offsetY = (it.y - height / 2f) - (it.y - height / 2f) * bigScale / smallScale
}
// 边界修正
fixOffset()
// 缩放动画开始
scaleAnimation.start()
} else {
scaleAnimation.reverse()
}

return super.onDoubleTap(e)
}

override fun onScroll(e1: MotionEvent?, e2: MotionEvent?, distanceX: Float, distanceY: Float): Boolean {
// 当前是放大状态
if (isLarge) {
// 刷新绘制位置
offsetX -= distanceX
offsetY -= distanceY
// 边界修正
fixOffset()
invalidate()
}
return super.onScroll(e1, e2, distanceX, distanceY)
}

}

inner class PhotoScaleGestureListener:ScaleGestureDetector.OnScaleGestureListener{
var initScale = 0f
override fun onScaleBegin(detector: ScaleGestureDetector?): Boolean {
// 初始缩放比例
initScale = currentScale
return true
}

override fun onScaleEnd(detector: ScaleGestureDetector?) {

}

override fun onScale(detector: ScaleGestureDetector?): Boolean {
// 如果当前缩放比 大于 最小缩放比 并且 非放大状态 或 当前缩放比 等于 最小缩放比 并且非放大状态
if ((currentScale > smallScale && !isLarge) || (currentScale == smallScale && !isLarge)){
// 设置为放大状态
isLarge = !isLarge
}
// 如果初始缩放比 * 缩放系数 小于 最小缩放比 赋值为最小缩放比 否则为初始缩放比 * 缩放系数
detector?.let {
currentScale = if (initScale * it.scaleFactor < smallScale){
smallScale
} else{
initScale * it.scaleFactor
}
}
invalidate()

return false
}
}
}

在布局中使用

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<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<com.tws.moments.views.PhotoView
android:id="@+id/photo"
android:layout_width="match_parent"
android:layout_height="match_parent"/>

</androidx.constraintlayout.widget.ConstraintLayout>

设置bitmap

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try {
photo.initBitmap(bitmap)
} catch (e: Exception) {
Log.i(TAG, "subscribe: ${e.stackTrace}")
}


动态换肤算是APP开发中常见的技术,最近公司的项目也是正好用到,需求是从后台下载皮肤包到本地,用户可以选择自己喜欢的皮肤包进行页面的动态换肤,增强用户体验和应用的趣味性。大致整理了一下实现思路,在此做个记录,如果有更好的方案,欢迎交流~

  1. 读取apk的内容
    异步加载本地目录的皮肤资源apk,通过反射调用AssetManager添加资源路径的方法将apk的资源加载进去,得到全新的AssetManager并注册,加载资源时使用新AssetManager的资源,新resource赋给全局的resource,切回默认app皮肤时,再赋值回默认的resource。
  2. 收集换肤的View相关数据,干预xml解析拦截需要换肤的view,Factory2中生产view时记录需要换肤的属性
  3. 观察者模式绑定被观察者-资源管理器和观察者-自定义的LayoutInflater.Factory2,BaseActivity实现统一换肤接口ISkinUpdate的逻辑调资源管理器加载皮肤APK。
  4. 执行换肤逻辑
    设置自定义的LayoutInflater.Factory2,拦截xml中原本解析的view返回一个新的view,判断当前view是否需要换肤,需要则直接设置相应属性,不需要则执行原本逻辑。

皮肤管理器

在Application中初始化皮肤管理器,继承Observable类,是一个可被观察的对象,需要通知观察者对象,主要负责加载本地皮肤包apk并更新皮肤resource对象到资源管理器,通知各个需要换肤的View更新UI,并记录当前使用的皮肤包路径

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public class SkinManager extends Observable {

private volatile static SkinManager instance;
/**
* Activity生命周期回调
*/
private ApplicationActivityLifecycle skinActivityLifecycle;
private Application mContext;

/**
* 初始化 必须在Application中先进行初始化
*
* @param application
*/
public static void init(Application application) {
if (instance == null) {
synchronized (SkinManager.class) {
if (instance == null) {
instance = new SkinManager(application);
}
}
}
}

private SkinManager(Application application) {
mContext = application;
//初始化sp,记录当前使用的皮肤
SkinPreference.init(application);
//资源管理类,从皮肤resource对象中加载资源
SkinResources.init(application);
//注册Activity生命周期,并设置被观察者
skinActivityLifecycle = new ApplicationActivityLifecycle(this);
application.registerActivityLifecycleCallbacks(skinActivityLifecycle);
//加载上次使用保存的皮肤
loadSkin(SkinPreference.getInstance().getSkin());
}

public static SkinManager getInstance() {
return instance;
}


/**
* 加载皮肤并更新resource到皮肤资源管理器
*
* @param skinPath 皮肤路径 如果为空则使用默认皮肤
*/
public void loadSkin(String skinPath) {
if (TextUtils.isEmpty(skinPath)) {
//还原默认皮肤
SkinPreference.getInstance().reset();
SkinResources.getInstance().reset();
} else {
try {
//宿主app的resources;
Resources appResource = mContext.getResources();
//反射创建AssetManager与Resource
AssetManager assetManager = AssetManager.class.newInstance();
//资源路径设置,压缩包的目录
Method addAssetPath = assetManager.getClass().getMethod("addAssetPath",
String.class);
addAssetPath.invoke(assetManager, skinPath);

//根据设备显示器信息与配置(横竖屏、语言等)创建新的皮肤Resources
Resources skinResource = new Resources(assetManager, appResource.getDisplayMetrics
(), appResource.getConfiguration());

//获取本地皮肤Apk(皮肤包) 包名,并应用皮肤
PackageManager mPm = mContext.getPackageManager();
PackageInfo info = mPm.getPackageArchiveInfo(skinPath, PackageManager
.GET_ACTIVITIES);
String packageName = info.packageName;
SkinResources.getInstance().applySkin(skinResource, packageName);

//记录当前使用的皮肤路径
SkinPreference.getInstance().setSkin(skinPath);


} catch (Exception e) {
e.printStackTrace();
}
}
//通知采集的View 更新皮肤
//被观察者改变,通知所有观察者
setChanged();
notifyObservers(null);
}

}
  • SP工具类,记录皮肤包路径
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    public class SkinPreference {
    private static final String SKIN_SHARED = "skins";
    private static final String KEY_SKIN_PATH = "skin-path";
    private volatile static SkinPreference instance;
    private final SharedPreferences mPref;

    public static void init(Context context) {
    if (instance == null) {
    synchronized (SkinPreference.class) {
    if (instance == null) {
    instance = new SkinPreference(context.getApplicationContext());
    }
    }
    }
    }

    public static SkinPreference getInstance() {
    return instance;
    }

    private SkinPreference(Context context) {
    mPref = context.getSharedPreferences(SKIN_SHARED, Context.MODE_PRIVATE);
    }

    public void setSkin(String skinPath) {
    mPref.edit().putString(KEY_SKIN_PATH, skinPath).apply();
    }

    public void reset() {
    mPref.edit().remove(KEY_SKIN_PATH).apply();
    }

    public String getSkin() {
    return mPref.getString(KEY_SKIN_PATH, null);
    }

    }

    监听Activity生命周期

    传入被观察者-皮肤管理器对象,缓存activity到对应自定义LayoutInflaterFactory对象的映射
  1. Activity被创建时,反射设置mFactorySet属性为false,设置自定义的LayoutInflaterFactory,并记录与当前activity的映射关系到map,添加自定义的LayoutInflaterFactory对象为皮肤管理器对象的观察者对象,接收皮肤管理器加载完成的通知
  2. Activity被销毁时,获取到对应的自定义LayoutInflaterFactory对象,移除对被观察者-皮肤管理器对象的监听
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    public class ApplicationActivityLifecycle implements Application.ActivityLifecycleCallbacks {

    private Observable mObserable; // 被观察者,皮肤管理器对象
    private ArrayMap<Activity, SkinLayoutInflaterFactory> mLayoutInflaterFactories = new
    ArrayMap<>(); // 记录activity到对应自定义LayoutInflaterFactory对象的映射

    public ApplicationActivityLifecycle(Observable observable) {
    mObserable = observable;
    }

    @Override
    public void onActivityCreated(Activity activity, Bundle savedInstanceState) {
    /**
    * 更新状态栏
    */
    SkinThemeUtils.updateStatusBarColor(activity);

    /**
    * 更新布局视图
    */
    //获得Activity的布局加载器
    LayoutInflater layoutInflater = activity.getLayoutInflater();

    try {
    //Android 布局加载器 使用 mFactorySet 标记是否设置过Factory
    //反射设置 mFactorySet 标签为false
    Field field = LayoutInflater.class.getDeclaredField("mFactorySet");
    field.setAccessible(true);
    field.setBoolean(layoutInflater, false);
    } catch (Exception e) {
    e.printStackTrace();
    }

    //设置自定义的LayoutInflaterFactory,并记录与当前activity的映射关系到map
    SkinLayoutInflaterFactory skinLayoutInflaterFactory = new SkinLayoutInflaterFactory
    (activity);
    LayoutInflaterCompat.setFactory2(layoutInflater, skinLayoutInflaterFactory);
    mLayoutInflaterFactories.put(activity, skinLayoutInflaterFactory);

    mObserable.addObserver(skinLayoutInflaterFactory);
    }

    @Override
    public void onActivityStarted(Activity activity) {

    }

    @Override
    public void onActivityResumed(Activity activity) {

    }

    @Override
    public void onActivityPaused(Activity activity) {

    }

    @Override
    public void onActivityStopped(Activity activity) {

    }

    @Override
    public void onActivitySaveInstanceState(Activity activity, Bundle outState) {

    }

    @Override
    public void onActivityDestroyed(Activity activity) {
    SkinLayoutInflaterFactory observer = mLayoutInflaterFactories.remove(activity);
    SkinManager.getInstance().deleteObserver(observer);
    }
    }

    皮肤资源管理器

    记录原始宿主App的resource对象和新的皮肤resource对象,从皮肤resource对象中获取对应的属性
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    public class SkinResources {

    private String mSkinPkgName;
    private boolean isDefaultSkin = true;

    // app原始的resource
    private Resources mAppResources;
    // 皮肤包的resource
    private Resources mSkinResources;

    private SkinResources(Context context) {
    mAppResources = context.getResources();
    }

    private volatile static SkinResources instance;
    public static void init(Context context) {
    if (instance == null) {
    synchronized (SkinResources.class) {
    if (instance == null) {
    instance = new SkinResources(context);
    }
    }
    }
    }

    public static SkinResources getInstance() {
    return instance;
    }

    public void reset() {
    mSkinResources = null;
    mSkinPkgName = "";
    isDefaultSkin = true;
    }

    public void applySkin(Resources resources, String pkgName) {
    mSkinResources = resources;
    mSkinPkgName = pkgName;
    //是否使用默认皮肤
    isDefaultSkin = TextUtils.isEmpty(pkgName) || resources == null;
    }

    /**
    * 1.通过原始app中的resId(R.color.XX)获取到自己的 名字
    * 2.根据名字和类型获取皮肤包中的ID
    */
    public int getIdentifier(int resId){
    if(isDefaultSkin){
    return resId;
    }
    String resName=mAppResources.getResourceEntryName(resId);
    String resType=mAppResources.getResourceTypeName(resId);
    int skinId=mSkinResources.getIdentifier(resName,resType,mSkinPkgName);
    return skinId;
    }

    /**
    * 输入主APP的ID,到皮肤APK文件中去找到对应ID的颜色值
    * @param resId
    * @return
    */
    public int getColor(int resId){
    if(isDefaultSkin){
    return mAppResources.getColor(resId);
    }
    int skinId=getIdentifier(resId);
    if(skinId==0){
    return mAppResources.getColor(resId);
    }
    return mSkinResources.getColor(skinId);
    }

    public ColorStateList getColorStateList(int resId) {
    if (isDefaultSkin) {
    return mAppResources.getColorStateList(resId);
    }
    int skinId = getIdentifier(resId);
    if (skinId == 0) {
    return mAppResources.getColorStateList(resId);
    }
    return mSkinResources.getColorStateList(skinId);
    }

    public Drawable getDrawable(int resId) {
    if (isDefaultSkin) {
    return mAppResources.getDrawable(resId);
    }
    //通过 app的resource 获取id 对应的 资源名 与 资源类型
    //找到 皮肤包 匹配 的 资源名资源类型 的 皮肤包的 资源 ID
    int skinId = getIdentifier(resId);
    if (skinId == 0) {
    return mAppResources.getDrawable(resId);
    }
    return mSkinResources.getDrawable(skinId);
    }


    /**
    * 可能是Color 也可能是drawable
    *
    * @return
    */
    public Object getBackground(int resId) {
    String resourceTypeName = mAppResources.getResourceTypeName(resId);

    if ("color".equals(resourceTypeName)) {
    return getColor(resId);
    } else {
    // drawable
    return getDrawable(resId);
    }
    }

    }

    自定义LayoutInflatorFactory

  3. 自定义LayoutInflatorFactory继承LayoutInflater.Factory2和Observer,是一个观察者对象,需要对皮肤管理器对象进行监听,接收到通知时应用皮肤,刷新状态栏,所有需要换肤的View刷新UI
  4. 解析xml创建View时,如果不是SDK自带的view就反射创建,如果是SDK的view尝试增加固定前缀,再反射创建,再修改View的属性刷新UI,达到换肤的效果
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    public class SkinLayoutInflaterFactory implements LayoutInflater.Factory2, Observer {
    // 待尝试的系统view固定前缀
    private static final String[] mClassPrefixList = {
    "android.widget.",
    "android.webkit.",
    "android.app.",
    "android.view."
    };


    private static final Class<?>[] mConstructorSignature = new Class[] {
    Context.class, AttributeSet.class};
    // 记录view名称与对应构造函数的映射
    private static final HashMap<String, Constructor<? extends View>> mConstructorMap =
    new HashMap<String, Constructor<? extends View>>();

    // 当选择新皮肤后需要替换View与之对应的属性
    // Activity的属性管理器
    private SkinAttribute skinAttribute;
    // 用于获取窗口的状态栏
    private Activity activity;

    // 初始化属性管理器
    public SkinLayoutInflaterFactory(Activity activity) {
    this.activity = activity;
    skinAttribute = new SkinAttribute();
    }

    @Override
    public View onCreateView(View parent, String name, Context context, AttributeSet attrs) {
    //换肤就是替换View的属性(src、background等)
    //创建 View,再修改View属性
    View view = createSDKView(name, context, attrs);
    if (null == view) {
    view = createView(name, context, attrs);
    }

    if (null != view) {
    //加载属性
    skinAttribute.look(view, attrs);
    }
    return view;
    }


    private View createSDKView(String name, Context context, AttributeSet
    attrs) {
    //如果包含 . 则不是SDK中的view,可能是自定义view包括support库中的View,尝试使用后面的构造方法反射创建
    if (-1 != name.indexOf('.')) {
    return null;
    }
    //不包含,是SDK中的view,在解析的name节点前,拼接上一些前缀如:android.widget. 尝试反射创建View
    for (int i = 0; i < mClassPrefixList.length; i++) {
    View view = createView(mClassPrefixList[i] + name, context, attrs);
    if(view!=null){
    return view;
    }
    }
    return null;
    }

    // 反射创建View
    private View createView(String name, Context context, AttributeSet
    attrs) {
    Constructor<? extends View> constructor = findConstructor(context, name);
    try {
    return constructor.newInstance(context, attrs);
    } catch (Exception e) {
    }
    return null;
    }

    private Constructor<? extends View> findConstructor(Context context, String name) {
    Constructor<? extends View> constructor = mConstructorMap.get(name);
    if (constructor == null) {
    try {
    Class<? extends View> clazz = context.getClassLoader().loadClass
    (name).asSubclass(View.class);
    constructor = clazz.getConstructor(mConstructorSignature);
    mConstructorMap.put(name, constructor);
    } catch (Exception e) {
    }
    }
    return constructor;
    }

    @Override
    public View onCreateView(String name, Context context, AttributeSet attrs) {
    return null;
    }

    //如果有人发送通知,这里就会执行
    @Override
    public void update(Observable o, Object arg) {
    SkinThemeUtils.updateStatusBarColor(activity);
    skinAttribute.applySkin();
    }
    }

    属性管理器

    记录所有View需要替换的属性名称,需要换肤的View与View的属性信息列表,遍历当前解析的View的所有属性,过滤该View需要替换的属性并记录,对需要换肤的View进行属性修改
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    public class SkinAttribute {
    private static final List<String> mAttributes = new ArrayList<>();
    // 需要替换的属性名称
    static {
    mAttributes.add("background");
    mAttributes.add("src");
    mAttributes.add("textColor");
    mAttributes.add("drawableLeft");
    mAttributes.add("drawableTop");
    mAttributes.add("drawableRight");
    mAttributes.add("drawableBottom");
    }

    //记录需要换肤的View与View的属性信息
    private List<SkinView> mSkinViews = new ArrayList<>();


    // 遍历当前View的属性,记录需要替换的属性并执行换肤,对View进行属性修改
    public void look(View view, AttributeSet attrs) {
    List<SkinPair> mSkinPars = new ArrayList<>();

    for (int i = 0; i < attrs.getAttributeCount(); i++) {
    // 获得属性名如textColor/background
    String attributeName = attrs.getAttributeName(i);
    // 如果这个属性是需要替换的属性
    if (mAttributes.contains(attributeName)) {
    // 比如color的值有多种格式
    // #
    // ?722727272
    // @722727272
    // 以#开头表示写死的颜色 不可用于换肤
    String attributeValue = attrs.getAttributeValue(i);
    if (attributeValue.startsWith("#")) {
    continue;
    }
    int resId;
    // 以?开头的,去主题资源中找属性值
    if (attributeValue.startsWith("?")) {
    int attrId = Integer.parseInt(attributeValue.substring(1));
    resId = SkinThemeUtils.getResId(view.getContext(), new int[]{attrId})[0];
    } else {
    // 正常以 @ 开头
    resId = Integer.parseInt(attributeValue.substring(1));
    }
    // 记录到当前View需要替换的属性表
    SkinPair skinPair = new SkinPair(attributeName, resId);
    mSkinPars.add(skinPair);
    }
    }
    // 如果当前view有属性需要替换,或者该属性是支持换肤的自定义view
    if (!mSkinPars.isEmpty() || view instanceof SkinViewSupport) {
    SkinView skinView = new SkinView(view, mSkinPars);
    // 执行换肤,进行View的属性修改
    skinView.applySkin();
    // 添加到缓存
    mSkinViews.add(skinView);
    }
    }


    /*
    对所有需要换肤的view执行换肤操作
    */
    public void applySkin() {
    for (SkinView mSkinView : mSkinViews) {
    mSkinView.applySkin();
    }
    }

    static class SkinView {
    View view;
    // 当前View需要替换的属性列表
    List<SkinPair> skinPairs;

    public SkinView(View view, List<SkinPair> skinPairs) {
    this.view = view;
    this.skinPairs = skinPairs;

    }
    /**
    * 对一个View中所有需要替换的属性进行修改
    */
    public void applySkin() {
    // 如果是支持换肤的自定义view调换肤接口
    applySkinSupport();
    // 遍历当前View需要替换的属性列表
    for (SkinPair skinPair : skinPairs) {
    Drawable left = null, top = null, right = null, bottom = null;
    switch (skinPair.attributeName) {
    case "background":
    Object background = SkinResources.getInstance().getBackground(skinPair
    .resId);
    //背景可能是 @color 也可能是 @drawable
    if (background instanceof Integer) {
    view.setBackgroundColor((int) background);
    } else {
    ViewCompat.setBackground(view, (Drawable) background);
    }
    break;
    case "src":
    background = SkinResources.getInstance().getBackground(skinPair
    .resId);
    if (background instanceof Integer) {
    ((ImageView) view).setImageDrawable(new ColorDrawable((Integer)
    background));
    } else {
    ((ImageView) view).setImageDrawable((Drawable) background);
    }
    break;
    case "textColor":
    ((TextView) view).setTextColor(SkinResources.getInstance().getColorStateList
    (skinPair.resId));
    break;
    case "drawableLeft":
    left = SkinResources.getInstance().getDrawable(skinPair.resId);
    break;
    case "drawableTop":
    top = SkinResources.getInstance().getDrawable(skinPair.resId);
    break;
    case "drawableRight":
    right = SkinResources.getInstance().getDrawable(skinPair.resId);
    break;
    case "drawableBottom":
    bottom = SkinResources.getInstance().getDrawable(skinPair.resId);
    break;
    default:
    break;
    }
    if (null != left || null != right || null != top || null != bottom) {
    ((TextView) view).setCompoundDrawablesWithIntrinsicBounds(left, top, right,
    bottom);
    }
    }
    }
    private void applySkinSupport() {
    if (view instanceof SkinViewSupport) {
    ((SkinViewSupport) view).applySkin();
    }
    }
    }

    static class SkinPair {
    //属性名
    String attributeName;
    //对应的资源id
    int resId;

    public SkinPair(String attributeName, int resId) {
    this.attributeName = attributeName;
    this.resId = resId;
    }
    }
    }

主题工具类

负责根据属性id获得theme中对应资源id的值,刷新状态栏颜色为皮肤包中定义的颜色

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public class SkinThemeUtils {

private static int[] APPCOMPAT_COLOR_PRIMARY_DARK_ATTRS = {
android.support.v7.appcompat.R.attr.colorPrimaryDark
};
private static int[] STATUSBAR_COLOR_ATTRS = {android.R.attr.statusBarColor, android.R.attr
.navigationBarColor
};


/**
* 获得theme中的属性中定义的 资源id
* @param context
* @param attrs
* @return
*/
public static int[] getResId(Context context, int[] attrs) {
int[] resIds = new int[attrs.length];
TypedArray a = context.obtainStyledAttributes(attrs);
for (int i = 0; i < attrs.length; i++) {
resIds[i] = a.getResourceId(i, 0);
}
a.recycle();
return resIds;
}



public static void updateStatusBarColor(Activity activity) {
//5.0以上才能修改
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
return;
}
//获得 statusBarColor 与 nanavigationBarColor (状态栏颜色)
//当与 colorPrimaryDark 不同时 以statusBarColor为准
int[] resIds = getResId(activity, STATUSBAR_COLOR_ATTRS);
int statusBarColorResId = resIds[0];
int navigationBarColor = resIds[1];

//如果获取到状态栏颜色资源id,那么设置状态栏颜色
if (statusBarColorResId != 0) {
int color = SkinResources.getInstance().getColor(statusBarColorResId);
activity.getWindow().setStatusBarColor(color);
} else {
//获得主色资源id
int colorPrimaryDarkResId = getResId(activity, APPCOMPAT_COLOR_PRIMARY_DARK_ATTRS)[0];
// 如果获取到主色资源id,那么设置状态栏颜色
if (colorPrimaryDarkResId != 0) {
int color = SkinResources.getInstance().getColor(colorPrimaryDarkResId);
activity.getWindow().setStatusBarColor(color);
}
}
// 如果获取到导航栏资源id,那么设置导航栏颜色
if (navigationBarColor != 0) {
int color = SkinResources.getInstance().getColor
(navigationBarColor);
activity.getWindow().setNavigationBarColor(color);

}
}

}


Android中使用多进程可以分配更多的内存,内存空间隔离,Android系统是用户空间+内核空间,用户程序崩溃了系统内核程序也不受影响,其中Server、Client、ServiceManager 运行于用户空间,Binder驱动运行于内核空间。Android的多进程通信就是采用Binder实现的。

Binder驱动建立了内核缓存区和内核数据接收缓存区的映射关系,以及内核数据接收缓存区和接收进程用户空间地址的映射关系,内核缓存区和接收进程的用户空间地址存在内存映射,发送方进程将数据复制到内核缓存区,相当于把数据发送到了接收进程的用户空间。

为了更了解Android进程间的通信机制,理解AIDL的原理,利用binder实现进程间的通信,记录一次手写AIDL的过程


定义一个bean类Book,实现序列化

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public class Book implements Parcelable {

private String name;
private int type;

public Book(String name, int type) {
this.name = name;
this.type = type;
}

protected Book(Parcel in) {
this.name = in.readString();
this.type = in.readInt();
}

public static final Creator<Book> CREATOR = new Creator<Book>() {
@Override
public Book createFromParcel(Parcel in) {
return new Book(in);
}

@Override
public Book[] newArray(int size) {
return new Book[size];
}
};

@Override
public int describeContents() {
return 0;
}

@Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeString(name);
dest.writeInt(type);
}

@Override
public String toString() {
return "Book{" +
"name='" + name + '\'' +
", type=" + type +
'}';
}
}

定义操作接口类IBookManager继承IInterface,定义数据操作的方法

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public interface IBookManager extends IInterface {

void addBook(Book book) throws RemoteException;

List<Book> getBookList() throws RemoteException;
}

定义抽象类Stub继承Binder类和IBookManager接口

  1. 实现onTransact方法,获取传入的参数,调用IBookManager接口的方法,这里暂不实现IBookManager的方法
  2. 返回IBookManager对象,需传入binder对象,如果与这个传入的binder对象在同一进程调用queryLocalInterface返回,否则把Binder传入Proxy对象返回一个远程的代理对象
  3. 返回Binder对象(自身)
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    public abstract class Stub extends Binder implements IBookManager {

    private static final String DESCRIPTOR = "com.enjoy.binder.common.IBookManager";

    public Stub() {
    this.attachInterface(this, DESCRIPTOR);
    }

    public static IBookManager asInterface(IBinder binder) {
    if ((binder == null)) {
    return null;
    }
    // 先查找本地接口对象,如果同一个进程直接返回
    IInterface iin = binder.queryLocalInterface(DESCRIPTOR);
    if ((iin != null) && (iin instanceof IBookManager)) {
    return (IBookManager) iin;
    }
    // 传入binder对象,返回一个远程的代理对象
    return new Proxy(binder);
    }

    // 返回自身对象
    @Override
    public IBinder asBinder() {
    return this;
    }

    @Override
    protected boolean onTransact(int code, Parcel data, Parcel reply, int flags) throws RemoteException {
    switch (code) {
    case INTERFACE_TRANSACTION:
    reply.writeString(DESCRIPTOR);
    return true;
    // 添加书,调用addBook接口
    case TRANSACTION_addBook:
    data.enforceInterface(DESCRIPTOR);
    // 获取传入的book对象
    Book arg0 = null;
    if ((0 != data.readInt())) {
    arg0 = Book.CREATOR.createFromParcel(data);
    }
    this.addBook(arg0);
    reply.writeNoException();
    return true;
    // 获取书的列表,调用getBookList接口
    case TRANSACTION_getBookList:
    data.enforceInterface(DESCRIPTOR);
    List<Book> result = this.getBookList();
    reply.writeNoException();
    reply.writeTypedList(result);
    return true;
    }
    return super.onTransact(code, data, reply, flags);
    }

    static final int TRANSACTION_addBook = IBinder.FIRST_CALL_TRANSACTION;
    static final int TRANSACTION_getBookList = IBinder.FIRST_CALL_TRANSACTION + 1;
    }
    定义一个代理类实现IBookManager接口,调用Stub类传入的Binder对象通过Stub类的onTransact方法进行数据操作
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    public class Proxy implements IBookManager {

    private static final String DESCRIPTOR = "com.enjoy.binder.common.IBookManager";

    private IBinder mRemote;
    // 保存Stub类传入的Binder对象
    public Proxy(IBinder remote) {
    mRemote = remote;
    }

    // 实现跨进程数据传输,调Binder对象的onTransact方法
    @Override
    public void addBook(Book book) throws RemoteException {
    Parcel data = Parcel.obtain(); // 跨进程传输数据对象
    Parcel reply = Parcel.obtain(); // 跨进程传输返回结果
    try {
    data.writeInterfaceToken(DESCRIPTOR);
    if ((book != null)) {
    data.writeInt(1);
    book.writeToParcel(data, 0);
    } else {
    data.writeInt(0);
    }
    // 调Stub的onTransact方法进行Stub.TRANSACTION_addBook处理,远端返回
    mRemote.transact(Stub.TRANSACTION_addBook, data, reply, 0);
    reply.readException();
    } finally {
    reply.recycle();
    data.recycle();
    }
    }

    // 实现跨进程数据传输,调Binder对象的onTransact方法
    @Override
    public List<Book> getBookList() throws RemoteException {
    Parcel data = Parcel.obtain(); // 跨进程传输数据对象
    Parcel reply = Parcel.obtain(); // 跨进程传输返回结果
    List<Book> result;
    try {
    data.writeInterfaceToken(DESCRIPTOR);
    // 调Stub的onTransact方法进行Stub.TRANSACTION_getBookList处理,远端返回
    mRemote.transact(Stub.TRANSACTION_getBookList, data, reply, 0);
    reply.readException();
    result = reply.createTypedArrayList(Book.CREATOR);
    } finally {
    reply.recycle();
    data.recycle();
    }
    return result;
    }

    // 返回Stub类传入的Binder对象
    @Override
    public IBinder asBinder() {
    return mRemote;
    }
    }
    定义一个工作在独立进程的远程服务类,定义数据源,创建Binder对象,实现数据操作接口IBookManager内addBook方法和getBookList方法的具体业务逻辑,并返回创建的Binder对象
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    public class RemoteService extends Service {

    private ArrayList<Book> books; // 定义数据源

    // 服务绑定后返回Binder对象
    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
    books = new ArrayList<>();
    Log.e("RemoteService", "success onBind");
    return iBinder;
    }

    // 创建一个Binder对象,实现IBookManager的数据操作方法,Stub类的对象在远端进程(独立进程)初始化
    private IBinder iBinder = new Stub() {
    @Override
    public void addBook(Book book) throws RemoteException {
    books.add(book);
    }

    @Override
    public List<Book> getBookList() throws RemoteException {
    return books;
    }
    };
    }
    在AndroidManifest中声明该服务在对立进程
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    <service
    android:name=".server.RemoteService"
    android:exported="true"
    android:process=":remote">
    <intent-filter>
    <action android:name="com.enjoy.binder" />
    <category android:name="android.intent.category.DEFAULT" />
    </intent-filter>
    </service>
    在主进程Activity中绑定远端服务进程,并通过binder对象调用数据操作方法
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    public class ClientActivity extends AppCompatActivity {

    private IBookManager iBookManager;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_main);
    // 绑定远端服务进程
    Intent intent = new Intent(this, RemoteService.class);
    intent.setAction("com.enjoy.binder");
    bindService(intent, connection, Context.BIND_AUTO_CREATE);
    // 点击,通过binder对象(远程代理对象)调用数据操作方法
    findViewById(R.id.btn).setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
    try {
    iBookManager.addBook(new Book("数据结构与算法", 3));
    List<Book> books = iBookManager.getBookList();
    } catch (RemoteException e) {
    e.printStackTrace();
    }
    }
    });
    }

    private ServiceConnection connection = new ServiceConnection() {
    @Override
    public void onServiceConnected(ComponentName name, IBinder service) {
    Log.e("ClientActivity", "onServiceConnected: success");
    iBookManager = Stub.asInterface(service);// Binder对象(远程代理对象)
    }

    @Override
    public void onServiceDisconnected(ComponentName name) {
    Log.e("ClientActivity", "onServiceDisconnected: success");
    iBookManager = null;
    }
    };
    }
    最后总结一下:
  4. Stub继承binder实现服务接口,onTransact根据code调服务接口
  5. Activity绑定远程服务,连接回调中获取Stub.asInterface,区分是否同一进程返回代理对象,如果是返回本地接口,否则返回远程服务onBinder返回的IBinder代理对象
  6. 代理类实现服务接口,数据打包,检查token,跨进程调transact序列化发送data和获取返回reply,客户端线程挂起
  7. 服务端实例化Stub并实现服务接口接收客户端请求并响应


对于WebView的重度使用,如游戏音视频比较耗内存的需求,把WebView放到一个新的进程可以申请到更大的内存,修改其Activity的进程,通过AIDL与主线程通信,与主进程隔离,避免WebView的不稳定性导致所在进程异常影响主进程的正常运行造成不必要的crash,在此记录一下封装过程,欢迎一起学习和讨论~


封装WebView

自定义WebView

初始化WebView默认设置,设置javascript调用接口,回调js的dispatchEvent方法做事件分发,web进程初始化主进程调用接口,加载url时重置touch状态,监听用户的触摸操作,通过是否为用户点击(touch状态)判断当前跳转是否为重定向

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open class BaseWebView @JvmOverloads constructor(
context: Context, attrs: AttributeSet? = null, defStyleAttr: Int = 0
) : WebView(context, attrs, defStyleAttr), BaseWebViewClient.WebviewTouch {
private var webViewCallBack: WebViewCallBack? = null
private var mHeaders: HashMap<String, String> ?= null
private var isTouchByUser: Boolean = false
private var redirectIntercept = false // 是否拦截重定向
protected var mContext: Context? = null

init {
init(context)
}
fun registerWebViewCallBack(webViewCallBack: WebViewCallBack) {
this.webViewCallBack = webViewCallBack
webViewClient = BaseWebViewClient(this, webViewCallBack, mHeaders, this, redirectIntercept)
}

fun setHeaders(mHeaders: HashMap<String, String>) {
this.mHeaders = mHeaders
}

fun setRedirectIntercept(intercept: Boolean){
redirectIntercept = intercept
}

protected fun init(context: Context?) {
mContext = context
// 初始化默认设置
WebviewDefaultSetting.getInstance().toSetting(this)
// javascript调用接口
addJavascriptInterface(this, "webview")
// web进程初始化主进程调用接口
CommandDispatcher.getInstance().initAidlConnect(getContext())
}


@JavascriptInterface
fun post(cmd: String, param: String) {
// web进程的主线程执行
Handler().post {
try {
if (webViewCallBack != null) {
CommandDispatcher.getInstance().execBySelf(context, cmd, param, this@BaseWebView)
}
} catch (e: Exception) {
e.printStackTrace()
}
}
}

override fun loadUrl(url: String) {
if (mHeaders == null) {
super.loadUrl(url)
} else {
super.loadUrl(url, mHeaders)
}
Log.e(TAG, "load url: $url")
resetAllStateInternal(url)
}

/**
* 处理header数据请求
* @param url String
* @param additionalHttpHeaders Map<String?, String?>
*/
override fun loadUrl(url: String, additionalHttpHeaders: Map<String?, String?>?) {
super.loadUrl(url, additionalHttpHeaders)
Log.e(TAG, "load url: $url")
resetAllStateInternal(url)
}

/**
* 回调js的callback方法
* @param response String?
*/
fun handleCallback(response: String?) {
if (!TextUtils.isEmpty(response)) {
val trigger = "javascript:callback($response)"
evaluateJavascript(trigger, null)
}
}

/**
* 回调js的cmd方法
* @param cmd String
* @param param Any?
*/
fun loadJS(cmd: String, param: Any?) {
val trigger = "javascript:" + cmd + "(" + Gson().toJson(param) + ")"
evaluateJavascript(trigger, null)
}

/**
* 回调js的dispatchEvent方法做事件分发
* @param name String
*/
fun dispatchEvent(name: String) {
val param = HashMap<String,String>(1)
param["name"] = name
loadJS("dispatchEvent", param)
}

private fun resetAllStateInternal(url: String) {
// url为空或者回调js方法直接返回
if (!TextUtils.isEmpty(url) && url.startsWith("javascript:")) {
return
}
resetAllState()
}

// 加载url时重置touch状态
protected fun resetAllState() {
isTouchByUser = false
}

override fun onTouchEvent(event: MotionEvent): Boolean {
when (event.action) {
MotionEvent.ACTION_DOWN -> isTouchByUser = true
}
return super.onTouchEvent(event)
}

companion object {
private const val TAG = "BaseWebView"
const val CONTENT_SCHEME = "file:///android_asset/"
}

override fun isTouchByUser(): Boolean {
return isTouchByUser
}
}

封装WebViewClient

回调接口逻辑,url跳转判断,重定向处理,对特殊链接统一处理,刷新处理,拦截指定url处理,判断是否加载完成,封装请求头,ssl错误处理

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class BaseWebViewClient(
val webView: WebView, // 封装的回调
val webViewCallBack: WebViewCallBack, // 封装的回调
val mHeaders: HashMap<String, String>?, // 请求头
val mWebviewTouch: WebviewTouch, // 是否有点击操作
val redirectIntercept: Boolean // 是否拦截重定向
) : WebViewClient() {
var isReady = false // 是否加载完成

interface WebviewTouch {
fun isTouchByUser(): Boolean
}

/**
* url重定向会执行此方法以及点击页面某些链接也会执行此方法
*
* @return true:表示当前url已经加载完成,即使url还会重定向都不会再进行加载 false 表示此url默认由系统处理,该重定向还是重定向,直到加载完成
*/
override fun shouldOverrideUrlLoading(view: WebView, url: String): Boolean {
Log.e(TAG, "shouldOverrideUrlLoading url: $url")
// 未发生过点击,当前是重定向且不拦截重定向
if (!mWebviewTouch.isTouchByUser() && !redirectIntercept) {
return super.shouldOverrideUrlLoading(view, url)
}
// 如果链接跟当前链接一样,表示刷新
if (webView.url == url) {
return super.shouldOverrideUrlLoading(view, url)
}
// 特殊链接处理,跳转手机自带应用
if (handleLinked(url)) {
return true
}
// 拦截指定url
if (webViewCallBack.overrideUrlLoading(url)) {
return true
}
// 控制页面中点开新的链接在当前webView中打开
view.loadUrl(url, mHeaders)
return true
}

@RequiresApi(api = Build.VERSION_CODES.N)
override fun shouldOverrideUrlLoading(view: WebView, request: WebResourceRequest): Boolean {
Log.e(TAG, "shouldOverrideUrlLoading url: " + request.url)
// 当前链接的重定向
if (!mWebviewTouch.isTouchByUser() && !redirectIntercept) {
return super.shouldOverrideUrlLoading(view, request)
}
// 如果链接跟当前链接一样,表示刷新
if (webView.url == request.url.toString()) {
return super.shouldOverrideUrlLoading(view, request)
}
// 需要跳转应用的特殊链接
if (handleLinked(request.url.toString())) {
return true
}
// 拦截指定url
if (webViewCallBack.overrideUrlLoading(request.url.toString())) {
return true
}
// 控制页面中点开新的链接在当前webView中打开
view.loadUrl(request.url.toString(), mHeaders)
return true
}

/**
* 支持电话、短信、邮件、地图跳转,跳转的都是手机系统自带的应用
*/
private fun handleLinked(url: String): Boolean {
if (url.startsWith(WebView.SCHEME_TEL)
|| url.startsWith(SCHEME_SMS)
|| url.startsWith(WebView.SCHEME_MAILTO)
|| url.startsWith(WebView.SCHEME_GEO)
) {
try {
val intent = Intent(Intent.ACTION_VIEW)
intent.data = Uri.parse(url)
webView.context.startActivity(intent)
} catch (ignored: ActivityNotFoundException) {
ignored.printStackTrace()
}
return true
}
return false
}

override fun onPageFinished(view: WebView?, url: String?) {
Log.e(TAG, "onPageFinished url:$url")
if (url == null) return
if (!TextUtils.isEmpty(url) && url.startsWith(CONTENT_SCHEME)) {
isReady = true
}
webViewCallBack.pageFinished(url)
}

override fun onPageStarted(view: WebView?, url: String?, favicon: Bitmap?) {
Log.e(TAG, "onPageStarted url: $url")
if (url == null) return
webViewCallBack.pageStarted(url)
}


override fun onScaleChanged(view: WebView?, oldScale: Float, newScale: Float) {
super.onScaleChanged(view, oldScale, newScale)
}

@TargetApi(21)
override fun shouldInterceptRequest(
view: WebView,
request: WebResourceRequest
): WebResourceResponse? {
return shouldInterceptRequest(view, request.url.toString())
}

/**
* 默认继续加载
* @param view WebView
* @param url String
* @return WebResourceResponse?
*/
override fun shouldInterceptRequest(view: WebView, url: String): WebResourceResponse? {
return null
}

/**
* webview加载错误处理
* @param view WebView
* @param errorCode Int
* @param description String
* @param failingUrl String
*/
override fun onReceivedError(
view: WebView,
errorCode: Int,
description: String,
failingUrl: String
) {
super.onReceivedError(view, errorCode, description, failingUrl)
Log.e(
TAG,
"webview error$errorCode + $description"
)
webViewCallBack.onError(errorCode,description,failingUrl)
}

/**
* SSL错误处理
* @param view
* @param handler
* @param error
*/
override fun onReceivedSslError(view: WebView, handler: SslErrorHandler, error: SslError) {
var message = webView.context.getString(R.string.ssl_error)
when (error.primaryError) {
SslError.SSL_UNTRUSTED -> message =
webView.context.getString(R.string.ssl_error_not_trust)
SslError.SSL_EXPIRED -> message = webView.context.getString(R.string.ssl_error_expired)
SslError.SSL_IDMISMATCH -> message =
webView.context.getString(R.string.ssl_error_mismatch)
SslError.SSL_NOTYETVALID -> message =
webView.context.getString(R.string.ssl_error_not_valid)
}
message += webView.context.getString(R.string.ssl_error_continue_open)
Log.v(TAG,message)
}

companion object {
private const val TAG = "WebviewClient"
const val SCHEME_SMS = "sms:"
}
}

封装WebChromeClient

处理文件选择和相册选择回调,js提示回调,进度刷新回调

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class BaseWebChromeClient(private val progressHandler: Handler) : WebChromeClient() {
private var mFilePathCallback: ValueCallback<Array<Uri>>? = null // 文件选择回调
private var mCameraPhotoPath: String? = null // 相册选择回调
override fun onReceivedTitle(view: WebView, title: String) {
super.onReceivedTitle(view, title)
if (view is ProgressWebView) {
if (!TextUtils.isEmpty(title)) {
val params = ArrayMap<String, String>()
params[WebConstants.COMMAND_UPDATE_TITLE_PARAMS] = title
// 调起刷新标题命令
(view as BaseWebView).post(WebConstants.COMMAND_UPDATE_TITLE, Gson().toJson(params))
}
}
}

// 进度更新回调
override fun onProgressChanged(view: WebView, newProgress: Int) {
var newProgress = newProgress
val message = Message()
if (newProgress == 100) {
message.obj = newProgress
progressHandler.sendMessageDelayed(message, 200)
} else {
if (newProgress < 10) {
newProgress = 10
}
message.obj = newProgress
progressHandler.sendMessage(message)
}
super.onProgressChanged(view, newProgress)
}

// js 提示回调
override fun onJsAlert(view: WebView, url: String, message: String, result: JsResult): Boolean {
AlertDialog.Builder(view.context)
.setTitle(R.string.dialog_alert_title)
.setMessage(message)
.setPositiveButton(
R.string.ok
) { dialoginterface, i -> //按钮事件
Toast.makeText(
view.context,
view.context.getString(R.string.ok) + " clicked.",
Toast.LENGTH_LONG
).show()
}.show()
//result.confirm();// 不加这行代码,会造成Alert劫持:Alert只会弹出一次,并且WebView会卡死
return true
}

//文件选择回调
override fun onShowFileChooser(
webView: WebView,
filePathCallback: ValueCallback<Array<Uri>>,
fileChooserParams: FileChooserParams
): Boolean {
mFilePathCallback?.onReceiveValue(null)
mFilePathCallback = filePathCallback
var takePictureIntent:Intent? = Intent(MediaStore.ACTION_IMAGE_CAPTURE)
if (takePictureIntent?.resolveActivity(webView.context.packageManager) != null) {
// Create the File where the photo should go
var photoFile: File? = null
try {
photoFile = createImageFile()
takePictureIntent.putExtra("PhotoPath", mCameraPhotoPath)
} catch (ex: IOException) {
ex.printStackTrace()
}

// Continue only if the File was successfully created
if (photoFile != null) {
mCameraPhotoPath = "file:" + photoFile.absolutePath
takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(photoFile))
} else {
takePictureIntent = null
}
}
if (takePictureIntent != null && mFilePathCallback != null){
(webView as BaseWebView).webViewCallBack?.onShowFileChooser(takePictureIntent, mFilePathCallback!!)
}
return true
}

/**
* More info this method can be found at
* http://developer.android.com/training/camera/photobasics.html
*
* @return
* @throws IOException
*/
@Throws(IOException::class)
private fun createImageFile(): File {
// Create an image file name
val timeStamp = SimpleDateFormat("yyyyMMdd_HHmmss").format(Date())
val imageFileName = "JPEG_" + timeStamp + "_"
val storageDir =
Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES)
return File.createTempFile(imageFileName, ".jpg", storageDir)
}
}

封装WebView回调接口

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interface WebViewCallBack {
fun pageStarted(url: String) // 页面开始加载
fun pageFinished(url: String) // 页面加载完成
fun overrideUrlLoading(url: String): Boolean // 拦截url
fun onError(errorCode: Int,description: String,failingUrl:String) // 错误回调
// 执行操作
fun onShowFileChooser(
cameraIntent: Intent,
filePathCallback: ValueCallback<Array<Uri>>
)
}

封装进度条

大部分app展示web页面顶部有个web页的加载进度条提升交互体验

定义进度条操作接口

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interface BaseProgressSpec {
fun show()
fun hide()
fun reset()
fun setProgress(newProgress: Int)
}

封装进度条控制逻辑

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class IndicatorHandler{
var baseProgressSpec: BaseProgressSpec? = null // 进度条接口

/**
* 单例
*/
companion object{
@Volatile private var instance: IndicatorHandler? = null
fun getInstance() = instance?: synchronized(this){
instance?: IndicatorHandler().also { instance = it }
}
}

/**
* 进度刷新
* @param newProgress Int
*/
fun progress(newProgress: Int) {
when (newProgress) {
0 -> {
reset()
}
in 1..10 -> {
showProgressBar()
}
in 11..94 -> {
setProgressBar(newProgress)
}
else -> {
setProgressBar(newProgress)
finish()
}
}
}


fun reset() {
baseProgressSpec?.reset()
}

fun finish() {
baseProgressSpec?.hide()
}

fun setProgressBar(n: Int) {
baseProgressSpec?.setProgress(n)
}

fun showProgressBar() {
baseProgressSpec?.show()
}

fun inJectProgressView(baseProgressSpec: BaseProgressSpec?):IndicatorHandler {
this.baseProgressSpec = baseProgressSpec
return this
}
}

自定义进度条

自定义FrameLayout布局,实现进度条操作接口,进度小于95时渲染匀速动画,大于等于95时渲染透明加减速动画

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class WebProgressBar @JvmOverloads constructor(
context: Context, attrs: AttributeSet? = null, defStyleAttr: Int = 0
) : FrameLayout(context, attrs, defStyleAttr),BaseProgressSpec {
/**
* 进度条颜色
*/
private var mColor = 0

/**
* 进度条的画笔
*/
private var mPaint: Paint = Paint()

/**
* 进度条动画
*/
private var mAnimator: Animator? = null

/**
* 控件的宽度
*/
private var mTargetWidth = 0

companion object{
/**
* 默认匀速动画最大的时长
*/
const val MAX_UNIFORM_SPEED_DURATION = 5 * 1000

/**
* 默认加速后减速动画最大时长
*/
const val MAX_DECELERATE_SPEED_DURATION = 600

/**
* 结束动画时长 , Fade out 。
*/
const val DO_END_ANIMATION_DURATION = 300

/**
* 当前匀速动画最大的时长
*/
var CURRENT_MAX_UNIFORM_SPEED_DURATION = MAX_UNIFORM_SPEED_DURATION

/**
* 当前加速后减速动画最大时长
*/
var CURRENT_MAX_DECELERATE_SPEED_DURATION = MAX_DECELERATE_SPEED_DURATION

/**
* 标志当前进度条的状态
*/
private var TAG = 0
const val UN_START = 0
const val STARTED = 1
const val FINISH = 2

/**
* 默认的高度
*/
var WEB_PROGRESS_DEFAULT_HEIGHT = 3
}

init {
init(context)
}

private fun init(context: Context) {
mColor = Color.parseColor("#c15d3e")
mPaint.isAntiAlias = true
mPaint.color = mColor
mPaint.isDither = true
mPaint.strokeCap = Paint.Cap.SQUARE
mTargetWidth = context.resources.displayMetrics.widthPixels
WEB_PROGRESS_DEFAULT_HEIGHT = dipToPx(context, 2.5f)
}

private fun setColor(color: Int) {
mColor = color
mPaint.color = color
}

fun setColor(color: String) {
this.setColor(Color.parseColor(color))
}

override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
val wMode = MeasureSpec.getMode(widthMeasureSpec)
val hMode = MeasureSpec.getMode(heightMeasureSpec)
var w = MeasureSpec.getSize(widthMeasureSpec)
var h = MeasureSpec.getSize(heightMeasureSpec)
if (wMode == MeasureSpec.AT_MOST) {
w =
if (w <= context.resources.displayMetrics.widthPixels) w else context.resources.displayMetrics.widthPixels
}
if (hMode == MeasureSpec.AT_MOST) {
h = WEB_PROGRESS_DEFAULT_HEIGHT
}
setMeasuredDimension(w, h)
}

private var currentProgress = 0f

override fun onDraw(canvas: Canvas?) {}

override fun dispatchDraw(canvas: Canvas) {
canvas.drawRect(
0f,
0f,
currentProgress / 100 * java.lang.Float.valueOf(this.width.toFloat()),
this.height.toFloat(),
mPaint
)
}

override fun show() {
if (visibility == GONE) {
this.visibility = VISIBLE
currentProgress = 0f
startAnim(false)
}
}

override fun onSizeChanged(w: Int, h: Int, oldw: Int, oldh: Int) {
super.onSizeChanged(w, h, oldw, oldh)
mTargetWidth = measuredWidth
val screenWidth = context.resources.displayMetrics.widthPixels
if (mTargetWidth >= screenWidth) {
CURRENT_MAX_DECELERATE_SPEED_DURATION = MAX_DECELERATE_SPEED_DURATION
CURRENT_MAX_UNIFORM_SPEED_DURATION = MAX_UNIFORM_SPEED_DURATION
} else {
//取比值
val rate = mTargetWidth / java.lang.Float.valueOf(screenWidth.toFloat())
CURRENT_MAX_UNIFORM_SPEED_DURATION = (MAX_UNIFORM_SPEED_DURATION * rate).toInt()
CURRENT_MAX_DECELERATE_SPEED_DURATION = (MAX_DECELERATE_SPEED_DURATION * rate).toInt()
}
}

fun setProgress(progress: Float) {
if (visibility == GONE) {
visibility = VISIBLE
}
if (progress < 95f) return
if (TAG != FINISH) {
startAnim(true)
}
}

override fun hide() {
TAG = FINISH
}


private var target = 0f


/**
* 开始动画
* @param isFinished Boolean
*/
private fun startAnim(isFinished: Boolean) {
val v: Float = if (isFinished) 100F else 95.toFloat()
if (mAnimator?.isStarted == true) {
mAnimator?.cancel()
}
// 刷新当前进度
currentProgress = if (currentProgress == 0f) 0.00000001f else currentProgress
// 进度为0-94,匀速动画
if (!isFinished) {
val mAnimator = ValueAnimator.ofFloat(currentProgress, v)
val residue = 1f - currentProgress / 100 - 0.05f
// 使用匀速插值器
mAnimator.interpolator = LinearInterpolator()
mAnimator.duration = (residue * CURRENT_MAX_UNIFORM_SPEED_DURATION).toLong()
mAnimator.addUpdateListener(mAnimatorUpdateListener)
mAnimator.start()
this.mAnimator = mAnimator
}
// 进度大于等于95后执行透明减速的动画
else {
var segment95Animator: ValueAnimator? = null
// 使用减速插值器
if (currentProgress < 95f) {
segment95Animator = ValueAnimator.ofFloat(currentProgress, 95f)
val residue = 1f - currentProgress / 100f - 0.05f
segment95Animator.duration =
(residue * CURRENT_MAX_DECELERATE_SPEED_DURATION).toLong()
segment95Animator.interpolator = DecelerateInterpolator()
segment95Animator.addUpdateListener(mAnimatorUpdateListener)
}
// alpha动画
val mObjectAnimator = ObjectAnimator.ofFloat(this, "alpha", 1f, 0f)
mObjectAnimator.duration = DO_END_ANIMATION_DURATION.toLong()
val mValueAnimatorEnd = ValueAnimator.ofFloat(95f, 100f)
mValueAnimatorEnd.duration = DO_END_ANIMATION_DURATION.toLong()
mValueAnimatorEnd.addUpdateListener(mAnimatorUpdateListener)
var mAnimatorSet = AnimatorSet()
mAnimatorSet.playTogether(mObjectAnimator, mValueAnimatorEnd)
if (segment95Animator != null) {
val mAnimatorSet1 = AnimatorSet()
// 执行alpha动画并刷新进度,后执行减速动画
mAnimatorSet1.play(mAnimatorSet).after(segment95Animator)
mAnimatorSet = mAnimatorSet1
}
mAnimatorSet.addListener(mAnimatorListenerAdapter)
mAnimatorSet.start()
mAnimator = mAnimatorSet
}
TAG = STARTED
target = v
}

// 动画刷新回调,刷新进度
private val mAnimatorUpdateListener =
ValueAnimator.AnimatorUpdateListener { animation ->
val t = animation.animatedValue as Float
currentProgress = t
this@WebProgressBar.invalidate()
}

// 监听动画完成
private val mAnimatorListenerAdapter: AnimatorListenerAdapter =
object : AnimatorListenerAdapter() {
override fun onAnimationEnd(animation: Animator) {
doEnd()
}
}

// 释放动画资源
override fun onDetachedFromWindow() {
super.onDetachedFromWindow()
/**
* animator cause leak , if not cancel;
*/
if (mAnimator?.isStarted == true) {
mAnimator?.cancel()
mAnimator = null
}
}

// 进度条执行完处理
private fun doEnd() {
if (TAG == FINISH && currentProgress == 100f) {
visibility = GONE
currentProgress = 0f
this.alpha = 1f
}
TAG = UN_START
}

// 状态重置
override fun reset() {
currentProgress = 0f
if (mAnimator?.isStarted == true) mAnimator?.cancel()
}

override fun setProgress(newProgress: Int) {
setProgress(newProgress.toFloat())
}
}

封装带进度条的WebView

设置自定义进度条,添加到WebView,传入主线程handler调用刷新进度条逻辑

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class ProgressWebView @JvmOverloads constructor(
context: Context, attrs: AttributeSet? = null, defStyleAttr: Int = 0
) : BaseWebView(context,attrs,defStyleAttr) {
private var indicatorHandler: IndicatorHandler? = null
private var progressBar: WebProgressBar = WebProgressBar(context)
// 主线程调刷新进度条逻辑
private val mHandler: Handler = object :Handler(Looper.getMainLooper()){
override fun handleMessage(msg: Message) {
val progress = msg.obj as Int
indicatorHandler?.progress(progress)
}
}

init {
init()
}

private fun init() {
progressBar.layoutParams = LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT,
ViewGroup.LayoutParams.WRAP_CONTENT
)
progressBar.visibility = GONE
addView(progressBar)
indicatorHandler = IndicatorHandler.getInstance().inJectProgressView(progressBar)
webChromeClient = BaseWebChromeClient(mHandler)
}
}

封装带WebView的Fragment

  • fragment基类,统一设置标题

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    open class BaseFragment: Fragment() {
    protected var mContext: Context? = null

    fun setTitle(titleId: Int) {
    activity?.setTitle(titleId)
    }

    fun setTitle(title: CharSequence?) {
    activity?.title = title
    }

    override fun onAttach(context: Context) {
    super.onAttach(context)
    this.mContext = context
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
    super.onViewCreated(view, savedInstanceState)
    if (mContext == null){
    mContext = context
    }
    }

    override fun getContext(): Context? {
    return if (super.getContext() == null) mContext else super.getContext()
    }
    }
  • 封装带Webview的fragment基类,处理带header请求,定义页面开始加载,结束加载,指定url拦截,加载错误回调,是否重定向拦截,网页返回按键处理,相册文件选择回调处理,页面销毁时释放WebView

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    abstract class BaseWebviewFragment : BaseFragment(), WebViewCallBack {
    companion object {
    const val INFO_HEADERS = "info_headers"
    const val REDIRECT_INTERCEPT = "redirect_intercept"
    const val REQUEST_CODE = 1
    }

    var webView: BaseWebView? = null
    protected var headers: HashMap<String, String> = HashMap()
    var webUrl: String? = null
    var pageStarted: ((String) -> Unit)? = null
    var pageFinished: ((String) -> Unit)? = null
    var overrideUrlLoading: ((String) -> Boolean)? = null
    var onError: ((Int, String, String) -> Unit)? = null
    var onShowFileChooser: ((Intent, ValueCallback<Array<Uri>>) -> Unit)? = null
    private var redirectIntercept = false
    @LayoutRes
    protected abstract fun getLayoutRes(): Int

    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    val bundle = arguments
    if (bundle != null) {
    webUrl = bundle.getString(WebConstants.INTENT_TAG_URL)
    if (bundle.containsKey(INFO_HEADERS)) {
    headers =
    bundle.getSerializable(INFO_HEADERS) as HashMap<String, String>
    redirectIntercept = bundle.getBoolean(REDIRECT_INTERCEPT)
    }
    }
    // 注册吐司命令
    CommandsManager.getInstance().registerCommand(ToastCommand())
    }

    override fun onCreateView(
    inflater: LayoutInflater,
    container: ViewGroup?,
    savedInstanceState: Bundle?
    ): View? {
    val view = inflater.inflate(getLayoutRes(), container, false)
    webView = view.findViewById(R.id.web_view)
    webView?.setHeaders(headers)
    webView?.setRedirectIntercept(redirectIntercept)
    return view
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
    super.onViewCreated(view, savedInstanceState)
    webView?.registerWebViewCallBack(this)
    loadUrl()
    }

    protected open fun loadUrl() {
    webUrl?.let {
    webView?.loadUrl(it)
    }
    }

    override fun onResume() {
    super.onResume()
    Log.v("BaseWebviewFragment","onResume")
    webView?.dispatchEvent("pageResume")
    webView?.onResume()
    }

    override fun onPause() {
    super.onPause()
    Log.v("BaseWebviewFragment","onPause")
    webView?.dispatchEvent("pagePause")
    webView?.onPause()
    }

    override fun onStop() {
    super.onStop()
    webView?.dispatchEvent("pageStop")
    }

    override fun onDestroyView() {
    super.onDestroyView()
    webView?.dispatchEvent("pageDestroy")
    clearWebView(webView)
    }

    open fun onKeyDown(keyCode: Int, event: KeyEvent): Boolean {
    return if (keyCode == KeyEvent.KEYCODE_BACK && event.action == KeyEvent.ACTION_DOWN) {
    onBackHandle()
    } else false
    }


    override fun pageStarted(url: String) {
    this.pageStarted?.invoke(url)
    }

    override fun pageFinished(url: String) {
    this.pageFinished?.invoke(url)
    }

    override fun overrideUrlLoading(url: String): Boolean {
    this.overrideUrlLoading?.let {
    return it.invoke(url)
    }
    return false
    }

    override fun onError(errorCode: Int, description: String, failingUrl: String) {
    onError?.invoke(errorCode, description, failingUrl)
    }

    /**
    * 处理返回
    * @return Boolean
    */
    protected open fun onBackHandle(): Boolean {
    return if (webView != null) {
    if (webView!!.canGoBack()) {
    webView?.goBack()
    true
    } else {
    false
    }
    } else false
    }

    private fun clearWebView(m: WebView?) {
    val m: WebView? = m ?: return
    // 非主线程退出
    if (Looper.myLooper() != Looper.getMainLooper()) return
    // 停止加载处理
    m?.stopLoading()
    if (m?.handler != null) {
    m.handler.removeCallbacksAndMessages(null)
    }
    // 移除webview的所有view
    m?.removeAllViews()
    // 获取父布局移除webview
    val mViewGroup: ViewGroup? = m?.parent as? ViewGroup
    mViewGroup?.removeView(m)
    // 回调置空
    m?.webChromeClient = null
    m?.webViewClient = null
    m?.tag = null
    // 清理历史并销毁
    m?.clearHistory()
    m?.destroy()
    }

    override fun onShowFileChooser(
    cameraIntent: Intent,
    filePathCallback: ValueCallback<Array<Uri>>
    ) {
    if (onShowFileChooser != null) {
    onShowFileChooser!!.invoke(cameraIntent, filePathCallback)
    } else {
    mFilePathCallback = filePathCallback
    //------------------------------------
    //弹出选择框有:相机、相册(Android9.0,Android8.0)
    //如果是小米Android6.0系统上,依然是:相机、相册、文件管理
    //如果安装了其他的相机(百度魔拍)、文件管理程序(ES文件管理器),也有可能会弹出
    val selectionIntent = Intent(Intent.ACTION_PICK, null)
    selectionIntent.type = "image/*"
    //------------------------------------
    val intentArray: Array<Intent?> = arrayOf(cameraIntent)
    val chooserIntent = Intent(Intent.ACTION_CHOOSER)
    chooserIntent.putExtra(Intent.EXTRA_TITLE, getString(R.string.file_chooser))
    chooserIntent.putExtra(Intent.EXTRA_INTENT, selectionIntent)
    chooserIntent.putExtra(Intent.EXTRA_INITIAL_INTENTS, intentArray)
    startActivityForResult(chooserIntent, REQUEST_CODE)
    }
    }

    private var mFilePathCallback: ValueCallback<Array<Uri>>? = null
    private val mCameraPhotoPath: String? = null

    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
    super.onActivityResult(requestCode, resultCode, data)
    when (requestCode) {
    REQUEST_CODE -> {
    var results: Array<Uri>? = null
    if (resultCode == Activity.RESULT_OK) {
    if (data == null) {
    if (mCameraPhotoPath != null) {
    Log.d("AppChooserFragment", mCameraPhotoPath)
    results = arrayOf(Uri.parse(mCameraPhotoPath))
    }
    } else {
    val dataString = data.dataString
    if (dataString != null) {
    results = arrayOf(Uri.parse(dataString))
    }
    }
    }
    mFilePathCallback?.onReceiveValue(results)
    mFilePathCallback = null
    }
    }
    }
    }
  • WebViewFragment实现类,header传参,是否拦截重定向,是否同步header到cookie

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    class WebviewFragment : BaseWebviewFragment() {
    override fun getLayoutRes(): Int {
    return R.layout.fragment_common_webview
    }

    companion object{
    fun newInstance(keyUrl: String, headers: HashMap<String, String> = HashMap(), redirectIntercept: Boolean,isSyncToCookie: Boolean): WebviewFragment? {
    val fragment = WebviewFragment()
    fragment.arguments = getBundle(keyUrl, headers, redirectIntercept)
    if (isSyncToCookie) {
    syncCookie(keyUrl, headers)
    }
    return fragment
    }

    private fun getBundle(url: String, headers: HashMap<String, String>, redirectIntercept:Boolean): Bundle? {
    val bundle = Bundle()
    bundle.putString(WebConstants.INTENT_TAG_URL, url)
    bundle.putSerializable(INFO_HEADERS, headers)
    bundle.putBoolean(REDIRECT_INTERCEPT, redirectIntercept)
    return bundle
    }


    /**
    * cookie同步到WebView
    *
    * @param url WebView要加载的url
    * @return true 同步cookie成功,false同步cookie失败
    * @Author JPH
    */
    private fun syncCookie(url: String?, map: Map<String, String?>): Boolean {
    val cookieManager = CookieManager.getInstance()
    for (key in map.keys) {
    cookieManager.setCookie(url, key + "=" + map[key])
    }
    val newCookie = cookieManager.getCookie(url)
    return !TextUtils.isEmpty(newCookie)
    }
    }

    }

    封装带WebView的Activity

    支持自定义标题布局,设置带WebView的Fragment并添加到Activity,按键处理,注册使用网页标题事件,网页Activity关闭事件

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    open class WebActivity : AppCompatActivity() {
    private var title: String? = null // 标题设置

    protected var webviewFragment: BaseWebviewFragment? = null
    // 标题布局可自定义
    @LayoutRes
    protected fun getLayoutTitle(): Int = R.layout.title_normal

    // 添加标题布局
    val titleView by lazy { LayoutInflater.from(this).inflate(getLayoutTitle(), fl_title) }

    companion object{
    // 启动入口
    fun startCommonWeb(context: Context, title: String?, url: String?,header: HashMap<String, String> = HashMap()) {
    val intent = Intent(context, WebActivity::class.java)
    intent.putExtra(WebConstants.INTENT_TAG_TITLE, title)
    intent.putExtra(WebConstants.INTENT_TAG_URL, url)
    intent.putExtra(WebConstants.INTENT_TAG_HEADERS, header)
    if (context is Service) {
    intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
    }
    context.startActivity(intent)
    }
    }

    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    CommandsManager.getInstance().registerCommand(titleUpdateCommand)
    setContentView(R.layout.activity_common_web)
    // 注册标题刷新回调
    // 设置标题和url
    title = intent.getStringExtra(WebConstants.INTENT_TAG_TITLE)
    val url = intent.getStringExtra(WebConstants.INTENT_TAG_URL)?:""

    // 如果是默认布局设置标题
    if (getLayoutTitle() == R.layout.title_normal){
    val textView = titleView.findViewById(R.id.tv_title) as TextView
    textView.text = title
    }

    // 填充webviewFragment
    val fm = supportFragmentManager
    val transaction = fm.beginTransaction()

    webviewFragment = null
    val params = intent.extras?.getSerializable(WebConstants.INTENT_TAG_HEADERS) as HashMap<String, String>
    webviewFragment = WebviewFragment.newInstance(
    url,
    params,
    redirectIntercept = false,
    isSyncToCookie = true
    )
    transaction.replace(R.id.web_view_fragment, webviewFragment as Fragment).commit()
    }

    override fun onKeyDown(keyCode: Int, event: KeyEvent?): Boolean {
    // 调用webviewFragment的按键回调
    if (webviewFragment != null && webviewFragment is BaseWebviewFragment && event != null) {
    val flag: Boolean = webviewFragment!!.onKeyDown(keyCode, event)
    if (flag) {
    return flag
    }
    }
    return super.onKeyDown(keyCode, event)
    }

    /**
    * 标题刷新命令
    */
    private val titleUpdateCommand: Command = object : Command {
    override fun name(): String {
    return WebConstants.COMMAND_UPDATE_TITLE
    }

    override fun exec(context: Context, params: ArrayMap<String, String>, resultBack: ResultBack) {
    if (params.containsKey(WebConstants.COMMAND_UPDATE_TITLE_PARAMS)) {
    if (getLayoutTitle() == R.layout.title_normal){
    val textView = titleView.findViewById(R.id.tv_title) as TextView
    textView.text = params[WebConstants.COMMAND_UPDATE_TITLE_PARAMS]
    }
    }
    }
    }

    /**
    * 默认title布局返回 回调
    * @param view View
    */
    fun back(view: View){
    finish()
    }

    override fun finish() {
    val map = ArrayMap<String, String>().apply {
    this[WebFinishCommand.FINISH_COMMAND_PARAMS] = "true"
    }
    CommandDispatcher.getInstance().execByOther(WebFinishCommand.FINISH_COMMAND, Gson().toJson(map))
    super.finish()
    }

    /**
    * 点击右侧button 回调
    * @param view View
    */
    fun clickRight(view: View){

    }
    }

    分发消息

  • 命令模式封装消息管理器,对当前分发的消息采用当前进程自行处理,或跨进程处理,根据传参判断是否需要回调给h5

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/**
* 命令实现接口
*/
interface Command {


// 命令名称
fun name():String
// 执行命令传参和定义返回接口
fun exec(context: Context, map: ArrayMap<String, String>, resultBack: ResultBack)
}
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/**
* 命令管理器
* @property instance CommandsManager?
* @property commands ArrayMap<String, Command>
*/
class CommandsManager private constructor(){
private var instance: CommandsManager? = null
// 命令缓存
val commands:ArrayMap<String, Command> = ArrayMap()

// 返回单例
companion object{
@Volatile private var instance:CommandsManager? = null
fun getInstance() = instance?: synchronized(this){
instance?:CommandsManager().also { instance = it }
}
}
/**
* 注册web进程处理的命令
* @param command Command
*/
fun registerCommand(command: Command) {
commands[command.name()] = command
}


/**
* 非UI线程执行
*/
fun execCommand(
context: Context,
action: String,
params: ArrayMap<String, String>?,
resultBack: ResultBack
) {
// 命令/传参不为空,执行命令逻辑
if (commands[action] != null && params != null) {
commands[action]?.exec(context, params, resultBack)
}
// 返回错误
else {
val aidlError =
AidlError(WebConstants.NO_METHOD, WebConstants.NO_METHOD_STR)
resultBack.onResult(WebConstants.FAILED, action, aidlError)
}
}


/**
* 判断命令是否存在
* @param action String?
* @return Boolean
*/
fun isCommandExist(action: String?): Boolean {
return commands[action] != null
}
}
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class CommandDispatcher {
/**
* json解析对象
*/
private val gson by lazy { Gson() }

// 跨进程通信接口
protected var iHandleAction: IHandleAction? = null


/**
* 单例返回
*/
companion object {
@Volatile
private var instance: CommandDispatcher? = null

fun getInstance() = instance ?: synchronized(this) {
return instance ?: CommandDispatcher().also { instance = it }
}
}

/**
* 跨进程连接
* @param context Context?
*/
fun initAidlConnect(context: Context) {
// 避免重复初始化
if (iHandleAction != null) {
return
}
// 开启子线程,获取跨进程调用实例
Thread {
iHandleAction = IHandleAction.Stub.asInterface(
ProcessConnector.getInstance(context).getAidlInterface()
)
}.start()
}

/** 其它进程执行命令
* @param cmd String
* @param params String
*/
fun execByOther(cmd: String, params: String) {
Log.i("CommandDispatcher", "${Process.myPid()}进程调跨进程处理,command: $cmd params: $params")
try {
iHandleAction?.handleAction(cmd, params, object : ICallback.Stub() {
override fun onResult(
responseCode: Int,
actionName: String?,
response: String?
) {
// 当前进程回调结果
handleCallback(responseCode, actionName, response)
}
})
} catch (e: Exception) {
Log.e("CommandDispatcher", "Command exec error!!!!", e)
}
}

/**
* 当前进程执行命令
* @param context Context
* @param cmd String
* @param params String
* @param webView WebView
*/
fun execBySelf(context: Context, cmd: String, params: String, webView: WebView? = null) {
Log.i("CommandDispatcher", "${Process.myPid()}进程自己处理,command: $cmd params: $params")
try {
// json传参数据反序列化为map对象
val mapParams = gson.fromJson<ArrayMap<String, String>>(
params,
ArrayMap::class.java
)
// 命令管理器执行该命令逻辑
CommandsManager.getInstance()
.execCommand(context, cmd, mapParams, object : ResultBack {
// 结果回调
override fun onResult(status: Int, action: String, result: Any?) {
handleCallback(status, action, gson.toJson(result), webView)
}
})
} catch (e: Exception) {
Log.e("CommandDispatcher", "Command exec error!!!!", e)
}
}

private fun handleCallback(
responseCode: Int, actionName: String?, response: String?,
webView: WebView? = null
) {
Log.d(
"CommandDispatcher",
String.format(
"Callback result: responseCode= %s, action= %s, result= %s",
responseCode,
actionName,
response
)
)
runOnUiThread(Runnable {
// 返回结果反序列化为json
val params = Gson().fromJson<ArrayMap<String, String>>(response, ArrayMap::class.java)
// 从传参判断是否需要回调给h5
if (webView != null && params[WebConstants.NATIVE2WEB_CALLBACK] != null && !TextUtils.isEmpty(
params[WebConstants.NATIVE2WEB_CALLBACK].toString()
)
) {
// web进程调js
if (webView is BaseWebView) {
webView.handleCallback(response)
}
}
})
}
}
  • 进程连接管理类,绑定另一个服务进程,连接断开时解绑重连,返回跨进程通信接口
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    class ProcessConnector private constructor(context: Context) {
    private var mContext: Context = context.applicationContext
    // 跨进程通信接口
    private var iHandleAction: IHandleAction? = null
    private var mConnectBinderPoolCountDownLatch: CountDownLatch = CountDownLatch(1) // 个数为1的同步变量

    // 单例对象
    companion object {
    @Volatile
    private var instance: ProcessConnector? = null
    fun getInstance(context: Context) = instance ?: synchronized(this) {
    instance ?: ProcessConnector(context).also { instance = it }
    }
    }

    init {
    connectToOtherProcessService()
    }

    // 绑定另一个服务进程
    @Synchronized
    private fun connectToOtherProcessService() {
    val targetClass = if(!isMainProcess(mContext)) RemoteBindMainService::class.java else MainBindRemoteService::class.java
    // 绑定主进程服务
    mContext.bindService(Intent(mContext,targetClass), object : ServiceConnection {

    // 服务断开
    override fun onServiceDisconnected(name: ComponentName) {
    Log.v("ServiceConnect","跨进程连接断开")
    }

    // 服务连接
    override fun onServiceConnected(name: ComponentName, service: IBinder) {
    Log.v("ServiceConnect","跨进程连接成功")
    // 绑定断开回调
    iHandleAction = IHandleAction.Stub.asInterface(service)
    try {
    iHandleAction?.asBinder()?.linkToDeath(object : IBinder.DeathRecipient {
    // 解绑重连
    override fun binderDied() {
    iHandleAction?.asBinder()?.unlinkToDeath(this, 0)
    iHandleAction = null
    connectToOtherProcessService()
    }
    }, 0)
    } catch (e: RemoteException) {
    e.printStackTrace()
    }
    mConnectBinderPoolCountDownLatch.countDown()
    }
    }, Context.BIND_AUTO_CREATE)

    // 线程同步阻塞
    try {
    mConnectBinderPoolCountDownLatch.await()
    } catch (e: InterruptedException) {
    e.printStackTrace()
    }
    }


    // 返回跨进程调用接口
    fun getAidlInterface(): IBinder? {
    return iHandleAction?.asBinder()
    }

    }

    跨进程通信

    跨进程接口定义

    定义AIDL跨进程调用接口
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    interface IHandleAction {
    void handleAction(String actionName, String jsonParams, in ICallback callback);
    }
    定义AIDL跨进程调用回调接口
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    interface ICallback {
    void onResult(int responseCode, String actionName, String response);
    }

    跨进程接口实现

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    class AidlInterface (val context: Context): IHandleAction.Stub() {
    private val gson: Gson by lazy { Gson() }
    override fun handleAction(
    actionName: String?,
    jsonParams: String?,
    callback: ICallback?
    ) {
    Log.v("AidlInterface","${Process.myPid()}进程正在跨进程执行命令$actionName")
    if (actionName != null){
    // 跨进程处理命令
    CommandsManager.getInstance().execCommand(context, actionName,
    gson.fromJson(jsonParams, ArrayMap::class.java) as? ArrayMap<String, String>, object : ResultBack {
    override fun onResult(status: Int, action: String, result: Any?) {
    try {
    // 原进程处理回调
    callback?.onResult(status, actionName, Gson().toJson(result))
    } catch (e: Exception) {
    e.printStackTrace()
    }
    }

    })
    }
    }

    }

    声明主进程服务和Web进程服务

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    /**
    * 主进程绑定web进程
    */
    class MainBindRemoteService : Service() {
    override fun onBind(intent: Intent?): IBinder? {
    val pid = Process.myPid()
    Log.d(
    "MainBindRemoteService", String.format(
    "web进程: %s",
    "当前进程ID为:$pid---主进程连接web进程成功"
    )
    )
    // web进程操作对象
    return AidlInterface(this)
    }

    }
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    /**
    * web绑定主进程服务
    */
    class RemoteBindMainService: Service() {
    override fun onBind(intent: Intent?): IBinder? {
    val pid = Process.myPid()
    Log.d(
    "RemoteBindMainService", String.format(
    "主进程: %s",
    "当前进程ID为:$pid----web连接主进程成功"
    )
    )
    // 主进程操作对象
    return AidlInterface(this)
    }
    }
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    <service android:name="com.example.weblib.service.MainBindRemoteService"
    android:process=":remoteweb"/>
    <service android:name="com.example.weblib.service.RemoteBindMainService" />
    最后利用ContentProvider初始化封装的SDK,兼容>=Android 9.0 不同进程中使用Webview需要配置不同的缓存目录
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    class WebInitializer : ContentProvider() {
    override fun onCreate(): Boolean {
    Log.v("SdkInitializer","WebLib初始化进程:${getProcessName(context!!)}")
    if (context == null) return true
    // >=Android 9.0 在不同进程中使用Webview需要配置缓存目录,配置WebLib进程使用的Webview缓存目录
    if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.P) {
    WebView.setDataDirectorySuffix("remote")
    }
    return true
    }
    ...
    }
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    <provider
    android:authorities="${applicationId}.library-installer"
    android:name="com.example.weblib.WebInitializer"
    android:multiprocess="true"
    android:process=":remoteweb"
    android:exported="false"/>


最近在做性能优化的东西,研究了一下相关的内存监测,卡顿监测,以及ANR监测开源框架,对里面的核心原理做了总结,并手写一份简易版以便加深印象,为后续搭建线上日志监控做铺垫,在此做一个记录,线上监控框架可根据业务在此基础上做扩展。收集必要的日志信息,排查问题及时修复BUG,提升性能和稳定性,也是每个Android工程师必不可少的技能。


BlockCanary

  1. 通过采样工具类,在子线程中获取主线程的堆栈信息并保存到Map,暴露一个接口返回采样结果
  2. 通过日志监控类,实现Printer接口,判断是否卡顿(采样开始到采样结束的时间间隔是否超过阈值),如果卡顿调用接口获取返回的采样结果在子线程中日志打印
  3. App出现卡顿,会阻塞主线程的dispatchMessage,主线程Looper的loop方法中有一个Printer在每个Message处理前后被调用,所以设置主线程的MessageLogging为自定义的Printer

    采样工具类

    开启一个采样子线程,设置原子变量记录本次是否采样保证多线程同步,避免重复开始和结束,开始采样post一个采样任务到子线程,存入当前时间戳和对应的主线程堆栈信息到Map中,如果本次仍然需采样继续延迟间隔时间执行采样任务,暴露一个获取主线程堆栈信息的接口方法,返回当前堆栈信息列表
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    public class StackSampler {
    public static final String SEPARATOR = "\r\n";
    public static final SimpleDateFormat TIME_FORMATTER =
    new SimpleDateFormat("MM-dd HH:mm:ss.SSS");
    private Handler mHandler;
    private Map<Long, String> mStackMap = new LinkedHashMap<>(); //保存的主线程堆栈信息
    private int mMaxCount = 100; // 最多保存100条
    private long mSampleInterval; // 采样时间间隔
    // 本次是否采样
    protected AtomicBoolean mShouldSample = new AtomicBoolean(false);

    public StackSampler(long sampleInterval) {
    mSampleInterval = sampleInterval;
    // 开启采样子线程
    HandlerThread handlerThread = new HandlerThread("block-canary-sampler");
    handlerThread.start();
    mHandler = new Handler(handlerThread.getLooper());
    }

    /**
    * 开始采样 执行堆栈
    */
    public void startDump() {
    // 避免重复开始
    if (mShouldSample.get()) {
    return;
    }
    // 设置采样标记
    mShouldSample.set(true);
    // 移除上一个采样任务,在采样间隔时间后执行采样
    mHandler.removeCallbacks(mRunnable);
    mHandler.postDelayed(mRunnable, mSampleInterval);
    }

    public void stopDump() {
    // 避免重复结束
    if (!mShouldSample.get()) {
    return;
    }
    // 设置采样标记
    mShouldSample.set(false);

    mHandler.removeCallbacks(mRunnable);
    }


    public List<String> getStacks(long startTime, long endTime) {
    ArrayList<String> result = new ArrayList<>();
    synchronized (mStackMap) {
    for (Long entryTime : mStackMap.keySet()) {
    // 记录时间大于开始时间小于结束时间就放入返回列表中
    if (startTime < entryTime && entryTime < endTime) {
    result.add(TIME_FORMATTER.format(entryTime)
    + SEPARATOR
    + SEPARATOR
    + mStackMap.get(entryTime));
    }
    }
    }
    return result;
    }

    private Runnable mRunnable = new Runnable() {
    @Override
    public void run() {
    StringBuilder sb = new StringBuilder();
    // 获得主线程堆栈信息并拼接到字符串
    StackTraceElement[] stackTrace = Looper.getMainLooper().getThread().getStackTrace();
    for (StackTraceElement s : stackTrace) {
    sb.append(s.toString()).append("\n");
    }
    synchronized (mStackMap) {
    //最多保存100条堆栈信息,到了数量上限移除
    if (mStackMap.size() == mMaxCount) {
    mStackMap.remove(mStackMap.keySet().iterator().next());
    }
    // 存入当前时间戳和对应的堆栈信息
    mStackMap.put(System.currentTimeMillis(), sb.toString());
    }
    // 如果本次要采样,设置延迟继续执行此任务
    if (mShouldSample.get()) {
    mHandler.postDelayed(mRunnable, mSampleInterval);
    }
    }
    };

    }

    卡顿监控工具类

    初始化采样工具类,开启打印日志子线程,记录采样的开始时间和结束时间,如果时间大于设定的卡顿阈值则判定为卡顿状态,调用采样工具类获取主线程堆栈信息
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    // 卡顿监控工具类
    public class LogMonitor implements Printer {

    private StackSampler mStackSampler; // 采样工具类
    private boolean mPrintingStarted = false; // 开始打印标记
    private long mStartTimestamp; // 开始时间戳
    private long mBlockThresholdMillis = 3000; // 卡顿阈值
    private long mSampleInterval = 1000; // 采样频率

    private Handler mLogHandler;

    public LogMonitor() {
    // 初始化采样工具类
    mStackSampler = new StackSampler(mSampleInterval);
    // 开启打印子线程
    HandlerThread handlerThread = new HandlerThread("block-canary-io");
    handlerThread.start();
    mLogHandler = new Handler(handlerThread.getLooper());
    }

    @Override
    public void println(String x) {
    //从if到else会执行消息分发,如果执行耗时超过阈值,输出卡顿信息
    if (!mPrintingStarted) {
    //记录开始时间
    mStartTimestamp = System.currentTimeMillis();
    mPrintingStarted = true;
    mStackSampler.startDump();
    } else {
    final long endTime = System.currentTimeMillis();
    mPrintingStarted = false;
    //出现卡顿,通知卡顿事件
    if (isBlock(endTime)) {
    notifyBlockEvent(endTime);
    }
    mStackSampler.stopDump();
    }
    }

    private void notifyBlockEvent(final long endTime) {
    // 获得卡顿时主线程堆栈信息在子线程打印
    mLogHandler.post(new Runnable() {
    @Override
    public void run() {
    List<String> stacks = mStackSampler.getStacks(mStartTimestamp, endTime);
    for (String stack : stacks) {
    Log.e("block-canary", stack);
    }
    }
    });
    }


    private boolean isBlock(long endTime) {
    return endTime - mStartTimestamp > mBlockThresholdMillis;
    }
    }

    卡顿监控入口

    设置主线程的MessageLogging为自定义的Printer
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    public class BlockCanary {
    public static void install() {
    LogMonitor logMonitor = new LogMonitor();
    Looper.getMainLooper().setMessageLogging(logMonitor);
    }
    }

LeakCanary

Java中WeakReference和ReferenceQueue联合使用是监控某个对象是否被gc回收的手段,LeakCanary正是利用这个原理实现的。

WeakReference和ReferenceQueue联合使用

创建一个对象,包装到弱引用对象中并关联引用队列,把对象置空,强制GC,取出引用队列的弱引用对象是否与关联时的弱引用对象相同

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public static void main(String[] args) {
// 创建一个引用队列
ReferenceQueue referenceQueue = new ReferenceQueue();
// 创建一个对象
Object obj = new Object();

//把obj放入弱引用对象,并和一个引用队列关联
//当obj被gc回收后,weakReference会被添加到与之关联的referenceQueue
WeakReference weakReference = new WeakReference(obj,referenceQueue);

//把obj置空,让它没有强引用
obj = null;
Runtime.getRuntime().gc(); //强制gc

try{
Thread.sleep(1000);
}catch (Exception e){}

Reference findRef = null;
do{
findRef = referenceQueue.poll();
//如果能找到上面的weakReference对象,说明obj被gc回收了
System.out.println("findRef = " +findRef + "是否等于上面的weakReference = " + (findRef == weakReference));
}while(findRef !=null);// 把所有referenceQueue的weakReference对象找出来
}

封装包含key和name的弱引用类

继承WeakReference弱引用类,方便根据key删除对象

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public class KeyWeakReference<T> extends WeakReference<T> {

private String key;
private String name;

public KeyWeakReference(T referent, String key, String name) {
super(referent);
this.key = key;
this.name = name;
}

public KeyWeakReference(T referent, ReferenceQueue<? super T> q, String key, String name) {
super(referent, q);
this.key = key;
this.name = name;
}

public String getKey() {
return key;
}

public void setKey(String key) {
this.key = key;
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

@Override
public String toString() {
final StringBuffer sb = new StringBuffer("KeyWeakReference{");
sb.append("key='").append(key).append('\'');
sb.append(", name='").append(name).append('\'');
sb.append('}');
return sb.toString();
}
}

监控工具类

创建一个观察对象Map,怀疑对象Map和引用队列,先清理一遍被GC的对象,遍历引用队列的所有弱引用对象,清理观察对象Map和怀疑对象Map中对应的对象,被监控的对象生成UUID作为key,把对象放入弱引用并与引用队列关联,放入到观察对象Map中,5秒后判断该对象是否还存在观察对象Map中,还存在则说明没有被GC,将该对象移动到怀疑对象Map

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public class Watcher {
// 观察对象Map
private HashMap<String, KeyWeakReference> watchedReferences = new HashMap<>();
// 怀疑对象Map
private HashMap<String, KeyWeakReference> retainedReferences = new HashMap<>();

//当被监视的对象被gc回收后,对象的弱引用就会被加入到引用队列
private ReferenceQueue queue = new ReferenceQueue();

public Watcher() {
}

/**
* 取出引用队列的所有弱引用对象,清理观察对象Map和怀疑对象Map中对应的对象
*/
private void removeWeaklyReachableReferences() {
KeyWeakReference findRef = null;
do {
// 取出引用队列的弱引用对象
findRef = (KeyWeakReference) queue.poll();
// 不为空说明对象被gc回收了,把对应的弱引用对象从观察对象Map,怀疑对象Map移除
if (findRef != null) {
// 根据key把它从观察对象Map移除
Reference removedRef = watchedReferences.remove(findRef.getKey());
// 如果removedRef为空,有可能被放入到怀疑对象Map了
// 尝试从怀疑对象Map中移除
if (removedRef == null) {
retainedReferences.remove(findRef.getKey());
}
}
} while (findRef != null);// 把referenceQueue的所有弱引用取出来
}

/**
* 根据key把对应的弱引用对象从观察对象Map移动到怀疑对象Map
*
* @param key
*/
private synchronized void moveToRetained(String key) {
System.out.println("加入到怀疑列表...");
// 加入怀疑对象Map前,做一次清理
removeWeaklyReachableReferences();
// 根据key从观察对象Map中去找弱引用对象
KeyWeakReference retainedRef = watchedReferences.remove(key);
// 发现还没有被删除,说明没有被回收
if (retainedRef != null) {
//从观察对象Map中移除,加入到怀疑对象Map
retainedReferences.put(key, retainedRef);
}
}


public void watch(Object watchedReference, String referenceName) {
//1. 先清理下观察对象Map和怀疑对象Map
removeWeaklyReachableReferences();
//2. 被监视的对象生成唯一的uuid作为key
final String key = UUID.randomUUID().toString();
//3. 被监视的对象放入weakReference,并和一个引用队列关联
KeyWeakReference reference = new KeyWeakReference(watchedReference, queue, key, "");
//4. 加入到观察对象Map
watchedReferences.put(key, reference);

//5. 延迟5秒后检查是否还在观察对象Map,如果还在,则加入到怀疑对象Map
Executor executor = Executors.newSingleThreadExecutor();
executor.execute(() -> {
Utils.sleep(5000);
moveToRetained(key);
});

}

// 获取泄漏对象Map
public HashMap<String, KeyWeakReference> getRetainedReferences() {
retainedReferences.forEach((key, keyWeakReference) -> {
System.out.println("key: " + key + " , obj: " + keyWeakReference.get() + " , keyWeakReference: " + keyWeakReference);
}
);
return retainedReferences;
}
}

监控泄漏对象

创建对象,调用监控工具类的监控方法,查看怀疑对象Map

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public static void main(String[] args) {
// 初始化监控工具类
Watcher watcher = new Watcher();
// 创建对象并开始对象监控
Object obj = new Object();
watcher.watch(obj,"");
try {
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
// 释放对象
obj = null;
// 强制GC
Runtime.getRuntime().gc();
sleep(100);
System.runFinalization();

System.out.println("查看是否在怀疑对象Map:" + watcher.getRetainedReferences().size());
}

ANRWatchDog

FileObserver

监控Android系统的anr日志目录/data/anr/,利用FileObserver监控目录下的文件操作,间接监控ANR问题

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public class ANRFileObserver extends FileObserver {

public ANRFileObserver(String path) {
super(path);
}

public ANRFileObserver(String path, int mask) {
super(path, mask);
}

@Override
public void onEvent(int event, @Nullable String path) {
switch (event)
{
case FileObserver.ACCESS://文件被访问
Log.i("Zero", "ACCESS: " + path);
break;
case FileObserver.ATTRIB://文件属性被修改,如 chmod、chown、touch 等
Log.i("Zero", "ATTRIB: " + path);
break;
case FileObserver.CLOSE_NOWRITE://不可写文件被 close
Log.i("Zero", "CLOSE_NOWRITE: " + path);
break;
case FileObserver.CLOSE_WRITE://可写文件被 close
Log.i("Zero", "CLOSE_WRITE: " + path);
break;
case FileObserver.CREATE://创建新文件
Log.i("Zero", "CREATE: " + path);
break;
case FileObserver.DELETE:// 文件被删除,如 rm
Log.i("Zero", "DELETE: " + path);
break;
case FileObserver.DELETE_SELF:// 自删除,即一个可执行文件在执行时删除自己
Log.i("Zero", "DELETE_SELF: " + path);
break;
case FileObserver.MODIFY://文件被修改
Log.i("Zero", "MODIFY: " + path);
break;
case FileObserver.MOVE_SELF://自移动,即一个可执行文件在执行时移动自己
Log.i("Zero", "MOVE_SELF: " + path);
break;
case FileObserver.MOVED_FROM://文件被移走,如 mv
Log.i("Zero", "MOVED_FROM: " + path);
break;
case FileObserver.MOVED_TO://文件被移来,如 mv、cp
Log.i("Zero", "MOVED_TO: " + path);
break;
case FileObserver.OPEN://文件被 open
Log.i("Zero", "OPEN: " + path);
break;
default:
//CLOSE : 文件被关闭,等同于(IN_CLOSE_WRITE | IN_CLOSE_NOWRITE)
//ALL_EVENTS : 包括上面的所有事件
Log.i("Zero", "DEFAULT(" + event + "): " + path);
break;
}
}
}

线程

开启ANR监控后台线程,检查是否ANR,通过检查标志位和时间差判断规定时间内是否执行完成,如果没执行完成则可能发生ANR卡住了,那么打印主线程堆栈信息并调用回调接口

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public class ANRWatchDog extends Thread {

private static final String TAG = "ANR";
private int timeout = 5000; // 超时阈值
private boolean ignoreDebugger = true; // 开启开关

static ANRWatchDog sWatchdog;

private Handler mainHandler = new Handler(Looper.getMainLooper());

private class ANRChecker implements Runnable {

private boolean mCompleted; // 是否完成
private long mStartTime; // 开始时间
private long executeTime = SystemClock.uptimeMillis(); // 执行时间

@Override
public void run() {
synchronized (ANRWatchDog.this) {
mCompleted = true;
executeTime = SystemClock.uptimeMillis();
}
}

void schedule() {
// 设置是否完成标记
mCompleted = false;
// 记录开始时间
mStartTime = SystemClock.uptimeMillis();
// 结束任务,在主线程中重置完成标记,记录结束时间
mainHandler.postAtFrontOfQueue(this);
}

boolean isBlocked() {
return !mCompleted || executeTime - mStartTime >= timeout;
}
}

// anr监听接口
public interface ANRListener {
void onAnrHappened(String stackTraceInfo);
}

private ANRChecker anrChecker = new ANRChecker();

private ANRListener anrListener;


public void addANRListener(ANRListener listener){
this.anrListener = listener;
}

public static ANRWatchDog getInstance(){
if(sWatchdog == null){
sWatchdog = new ANRWatchDog();
}
return sWatchdog;
}

private ANRWatchDog(){
super("ANR-WatchDog-Thread");
}

@TargetApi(Build.VERSION_CODES.JELLY_BEAN)
@Override
public void run() {
// 设置为后台线程
Process.setThreadPriority(Process.THREAD_PRIORITY_BACKGROUND);
while(true){
// 没有被打断停止
while (!isInterrupted()) {
synchronized (this) {
// 检查是否anr
anrChecker.schedule();
long waitTime = timeout;
long start = SystemClock.uptimeMillis();
// 防止假唤醒
while (waitTime > 0) {
try {
// 等待超时时长后检查标志位
wait(waitTime);
} catch (InterruptedException e) {
Log.w(TAG, e.toString());
}
// 发现没有到阈值继续休眠
waitTime = timeout - (SystemClock.uptimeMillis() - start);
}
// 如果没有阻塞跳过此次循环
if (!anrChecker.isBlocked()) {
continue;
}
}
// 如果开关关闭并且在调试跳过此次循环
if (!ignoreDebugger && Debug.isDebuggerConnected()) {
continue;
}
// 打印堆栈信息并回调
String stackTraceInfo = getStackTraceInfo();
if (anrListener != null) {
anrListener.onAnrHappened(stackTraceInfo);
}
}
anrListener = null;
}
}

// 获取主线程堆栈信息返回字符串
private String getStackTraceInfo() {
StringBuilder stringBuilder = new StringBuilder();
for (StackTraceElement stackTraceElement : Looper.getMainLooper().getThread().getStackTrace()) {
stringBuilder
.append(stackTraceElement.toString())
.append("\r\n");
}
return stringBuilder.toString();
}
}

ANRWatchDog.getInstance().addANRListener(new ANRWatchDog.ANRListener() {
@Override
public void onAnrHappened(String stackTraceInfo) {
Log.i(TAG, "发生了ANR: "+ stackTraceInfo);
}
});
ANRWatchDog.getInstance().start();


最近公司的项目做性能优化,正在折腾Fragment懒加载的东西,由于项目迁移到了AndroidX,懒加载方案和以前有所不同,不过总体来说代码量少了很多,正好可以对新老版本的懒加载方案做一个对比,下面是关于AndroidX前和AndroidX后的fragment懒加载方案总结


AndroidX之前采用旧懒加载方案

4步优化

  1. View已加载且fragment可见时懒加载
  • 当onViewCreated()方法执行时,表明View已经加载完毕,isViewCreated标记为true,并调lazyLoad()方法
  • 当setUserVisibleHint(boolean isVisibleToUser)执行时,isVisibleToUser为true并调lazyLoad()方法
  • 在lazyLoad()方法双重标记判断,再进行停止一切/加载数据事件分发
  • 定义抽象方法loadData(),子类重写进行加载数据
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    private boolean isViewCreated = false;
    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    ...
    isViewCreated = true; // View已加载
    // 此时正好可见
    if (getUserVisibleHint()) {
    setUserVisibleHint(true);
    }

    return rootView;
    }

    @Override
    public void setUserVisibleHint(boolean isVisibleToUser) {
    super.setUserVisibleHint(isVisibleToUser);
    // View已加载
    if (isViewCreated) {
    // 根据当前可见状态分发事件
    if (isVisibleToUser) {
    dispatchUserVisibleHint(true);
    } else {
    dispatchUserVisibleHint(false);
    }
    }
    }

    private void dispatchUserVisibleHint(boolean visibleState) {
    if (visibleState) {
    // 加载网络数据请求
    onFragmentLoad();
    } else {
    // 停止网络数据请求
    onFragmentLoadStop();
    }
    }

    public void onFragmentLoadStop() {
    E("onFragmentLoadStop");
    }

    public void onFragmentLoad() {
    E("onFragmentLoad");
    }
  1. 记录上一次状态与当前状态比较,保证变化过程,状态未改变不需要分发事件
  • 从可见到不可见,停止一切操作
  • 从不可见到可见,加载数据操作
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    private boolean isVisibleStateUP = false; // 记录上一次可见的状态
    @Override
    public void setUserVisibleHint(boolean isVisibleToUser) {
    super.setUserVisibleHint(isVisibleToUser);

    if (isViewCreated) {
    // 当前可见且上一次不可见
    if (isVisibleToUser && !isVisibleStateUP) {
    dispatchUserVisibleHint(true);
    }
    // 当前不可见且上一次可见
    else if (!isVisibleToUser && isVisibleStateUP){
    dispatchUserVisibleHint(false);
    }

    }
    }

    private void dispatchUserVisibleHint(boolean visibleState) {
    this.isVisibleStateUP = visibleState;
    if (visibleState) {
    // 加载网络数据请求
    onFragmentLoad();
    } else {
    // 停止网络数据请求
    onFragmentLoadStop();
    }
    }
  1. 启动新的Activity没有分发事件
  • 除了onCreate和setUserVisibleHint在onResume/onPause中也要分发事件
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    @Override
    public void onResume() {
    super.onResume();
    // 当前可见且上一次不可见
    if (getUserVisibleHint() && !isVisibleStateUP) {
    dispatchUserVisibleHint(true);
    }
    }

    @Override
    public void onPause() {
    super.onPause();
    // 当前不可见且上一次可见
    if (getUserVisibleHint() && isVisibleStateUP) {
    dispatchUserVisibleHint(false);
    }
    }
  1. 双重嵌套下子Fragment无法接收到事件
    父fragment不可见直接返回,判断当前fragment是否可见,手动遍历分发每个子fragment停止一切操作/加载数据事件
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    // 判断父fragment是否可见 
    private boolean isParentInvisible() {
    // 获取父fragment
    Fragment parentFragment = getParentFragment();
    // 父fragment是懒加载fragment的实例
    if (parentFragment instanceof LazyFragment) {
    LazyFragment fragment = (LazyFragment) parentFragment;
    // 父fragment不可见
    return !fragment.isVisibleStateUP;
    }
    return false;
    }

    private void dispatchUserVisibleHint(boolean visibleState) {
    this.isVisibleStateUP = visibleState;
    // 当前fragment可见且父fragment不可见,不分发事件
    if (visibleState && isParentInvisible()) {
    return;
    }

    if (visibleState) {
    onFragmentLoad();
    // 分发子fragment可见事件
    dispatchChildVisibleState(true);

    } else {
    onFragmentLoadStop();
    // 分发子fragment不可见事件
    dispatchChildVisibleState(false);
    }
    }

    protected void dispatchChildVisibleState(boolean state) {
    FragmentManager fragmentManager = getChildFragmentManager();
    List<Fragment> fragments = fragmentManager.getFragments();
    if (fragments != null) {
    // 遍历子Fragment分发事件
    for (Fragment fragment: fragments) {
    // fragment是懒加载实例未被隐藏且可见
    if (fragment instanceof LazyFragment &&
    !fragment.isHidden() &&
    fragment.getUserVisibleHint()) {
    ((LazyFragment5)fragment).dispatchUserVisibleHint(state);
    }
    }
    }
    }

    AndroidX之后采用新懒加载方案

    Google在Androidx在FragmentTransaction中增加了setMaxLifecycle方法控制Fragment 调用的最大的生命周期函数。该方法可以设置活跃状态下Fragment最大状态,如果该Fragment 超过了设置的最大状态,会强制将Fragment降级到正确的状态

    viewPager下设置adapter的behavior

    BEHAVIOR_SET_USER_VISIBLE_HINT:Fragment对用户可见状态发生改变时,setUserVisibleHint方法会被调用。
    BEHAVIOR_RESUME_ONLY_CURRENT_FRAGMENT:当前选中的Fragment在Lifecycle.State#RESUMED状态,其他不可见的 Fragment限制在Lifecycle.State#STARTED状态
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    open class FragmentLazyPagerAdapter(
    fragmentManager: FragmentManager,
    private val fragments: MutableList<Fragment>,
    private val titles: MutableList<String>
    ) : FragmentPagerAdapter(fragmentManager, BEHAVIOR_RESUME_ONLY_CURRENT_FRAGMENT) {

    override fun getItem(position: Int) = fragments[position]

    override fun getCount() = fragments.size

    override fun getPageTitle(position: Int) = titles[position]

    }

    封装懒加载fragment

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    abstract class LazyFragment : Fragment() {

    // 是否加载过标记
    private var isLoaded = false

    override fun onResume() {
    super.onResume()
    if (!isLoaded) {
    lazyInit()
    Log.d(TAG, "lazyInit:!!!!!!!")
    isLoaded = true
    }
    }

    override fun onDestroyView() {
    super.onDestroyView()
    isLoaded = false
    }

    abstract fun lazyInit()
    }

    add/show/hide时设置最大生命周期(未使用viewPager)

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    // 初始化fragment
    private fun loadFragmentsTransaction(
    @IdRes containerViewId: Int,
    showPosition: Int,
    fragmentManager: FragmentManager,
    vararg fragments: Fragment
    ) {
    if (fragments.isNotEmpty()) {
    fragmentManager.beginTransaction().apply {
    for (index in fragments.indices) {
    val fragment = fragments[index]
    add(containerViewId, fragment, fragment.javaClass.name)
    if (showPosition == index) {
    setMaxLifecycle(fragment, Lifecycle.State.RESUMED)
    } else {
    hide(fragment)
    setMaxLifecycle(fragment, Lifecycle.State.STARTED)
    }
    }

    }.commit()
    } else {
    throw IllegalStateException(
    "fragments must not empty"
    )
    }
    }

    // 展示/隐藏fragment
    private fun showHideFragmentTransaction(fragmentManager: FragmentManager, showFragment: Fragment) {
    fragmentManager.beginTransaction().apply {
    show(showFragment)
    setMaxLifecycle(showFragment, Lifecycle.State.RESUMED)

    //获取其中所有的fragment,其他的fragment进行隐藏
    val fragments = fragmentManager.fragments
    for (fragment in fragments) {
    if (fragment != showFragment) {
    hide(fragment)
    setMaxLifecycle(fragment, Lifecycle.State.STARTED)
    }
    }
    }.commit()
    }

    Fragment嵌套下的问题

    第一次初始化时,同级不可见的Fragment仍然要调生命周期方法,需增加Fragment是否可见的判断
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    abstract class LazyFragment : Fragment() {

    private var isLoaded = false

    override fun onResume() {
    super.onResume()
    //增加Fragment是否可见的判断
    if (!isLoaded && !isHidden) {
    lazyInit()
    Log.d(TAG, "lazyInit:!!!!!!!")
    isLoaded = true
    }
    }

    override fun onDestroyView() {
    super.onDestroyView()
    isLoaded = false
    }

    abstract fun lazyInit()

    }

    ViewPager2懒加载

    最新的ViewPager2默认就实现了懒加载,可以说不用任何处理

但是ViewPager2中的RecyclerView可以缓存Fragment的数量是有限的,会造成Fragment的多次销毁和创建,也可通过setOffscreenPageLimit()方法设置预加载数量,再用AndroidX下的懒加载fragment方式去处理


加密技术这块不仅涉及到很多JAVA基础,加密技术还涉及到很多Android底层知识,JAVA反射,JAVA IO,apk的启动流程,类的加载机制,dex文件的构造,APK打包的过程,而这些东西又正好是面试的常考点,是深入学习Android的必经之路,这次从原理入手,手写一个简单的加固框架,在这里做一个记录,如果有不对的地方欢迎指出和交流。


加固的主要目的是为了防止反编译,代码遭到阅读和窃取甚至重新打包上架的事情发生,那反编译的过程是什么呢?

  1. zip解压apk
  2. dex2jar把class.dex转成jar包
  3. jd-gui看class文件源码

加固的原理

所以加固的关键是对dex文件用加密算法进行加密,防止可执行部分的源码被阅读,此时就需要一个壳程序负责解密原dex文件,然后再合并原dex和壳dex重新签名打包成新的apk,运行时壳程序解密,获得原dex重新手动类加载

apk的打包流程

  1. APT工具处理资源文件(xml资源如布局、AndroidManifest),生成R.java
  2. AIDL工具处理AIDL文件,生成相应的Java文件
  3. Javac工具编译Java,生成Class文件
  4. DX工具将Class文件转换成DEX文件
  5. ApkBuilder工具将资源文件和DEX文件打包成APK
  6. KeyStore签名APK
  7. 正式版APK用ZipAlign工具对齐

实现加固

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public static void main(String[] args) throws Exception {

byte[] mainDexData; // 存储源apk中的源dex文件
byte[] aarData; // 存储壳中的壳dex文件
byte[] mergeDex; // 存储壳dex 和源dex 的合并的新dex文件

// 删除source/apk/temp目录下所有文件
File tempFileApk = new File("source/apk/temp");
if (tempFileApk.exists()) {
File[]files = tempFileApk.listFiles();
for(File file: files){
if (file.isFile()) {
file.delete();
}
}
}
// 删除source/aar/temp目录下所有文件
File tempFileAar = new File("source/aar/temp");
if (tempFileAar.exists()) {
File[]files = tempFileAar.listFiles();
for(File file: files){
if (file.isFile()) {
file.delete();
}
}
}

//第一步 处理原始apk 加密dex
AES.init(AES.DEFAULT_PWD);
//待加固的apk
File apkFile = new File("source/apk/app-debug.apk");
//创建临时文件夹
File newApkFile = new File(apkFile.getParent() + File.separator + "temp");
if(!newApkFile.exists()) {
newApkFile.mkdirs();
}
//加密apk文件并写入到临时文件夹获取主dex
File mainDexFile = AES.encryptAPKFile(apkFile,newApkFile);
//临时文件夹存在,重命名dex文件
if (newApkFile.isDirectory()) {
File[] listFiles = newApkFile.listFiles();
for (File file : listFiles) {
if (file.isFile()) {
if (file.getName().endsWith(".dex")) {
String name = file.getName();
System.out.println("rename step1:"+name);
int cursor = name.indexOf(".dex");
String newName = file.getParent()+ File.separator + name.substring(0, cursor) + "_" + ".dex";
System.out.println("rename step2:"+newName);
file.renameTo(new File(newName));
}
}
}
}

// 第二步 处理aar 获得壳dex,其实这就是一个解密程序
File aarFile = new File("source/aar/mylibrary-debug.aar");
// jar包转dex文件
File aarDex = Dx.jar2Dex(aarFile);
//读取dex文件为byte数组
aarData = Utils.getBytes(aarDex);
// 创建一个classes.dex文件
File tempMainDex = new File(newApkFile.getPath() + File.separator + "classes.dex");
if (!tempMainDex.exists()) {
tempMainDex.createNewFile();
}
// 写入byte数组到classes.dex文件
FileOutputStream fos = new FileOutputStream(tempMainDex);
byte[] fbytes = Utils.getBytes(aarDex);
fos.write(fbytes);
fos.flush();
fos.close();


/**
* 第三步 打包签名
*/
// 创建未签名apk的文件夹
File unsignedApk = new File("result/apk-unsigned.apk");
unsignedApk.getParentFile().mkdirs();
// 合并壳dex和加密dex,压缩newApkFile中的文件为unsignedApk
Zip.zip(newApkFile, unsignedApk);
// 对unsignedApk文件签名输出签名后的文件apk-signed.apk
File signedApk = new File("result/apk-signed.apk");
Signature.signature(unsignedApk, signedApk);
}
}

Zip压缩工具类

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public class Zip {

// 解压文件到目标文件夹
public static void unZip(File zip, File dir) {
try {
// 删除已存在的目标文件夹
dir.delete();
// 包装成压缩文件对象
ZipFile zipFile = new ZipFile(zip);
// 获取被压缩的所有文件
Enumeration<? extends ZipEntry> entries = zipFile.entries();
// 遍历被压缩的文件
while (entries.hasMoreElements()) {
ZipEntry zipEntry = entries.nextElement();
String name = zipEntry.getName();
// 如果是META-INF/CERT.RSA,META-INF/CERT.SF,META-INF/MANIFEST.MF文件就跳过
if (name.equals("META-INF/CERT.RSA") || name.equals("META-INF/CERT.SF") || name
.equals("META-INF/MANIFEST.MF")) {
continue;
}
// 如果当前压缩文件不是一个文件夹,就输出到目标文件夹
if (!zipEntry.isDirectory()) {
File file = new File(dir, name);
if (!file.getParentFile().exists()) file.getParentFile().mkdirs();
FileOutputStream fos = new FileOutputStream(file);
InputStream is = zipFile.getInputStream(zipEntry);
byte[] buffer = new byte[1024];
int len;
while ((len = is.read(buffer)) != -1) {
fos.write(buffer, 0, len);
}
is.close();
fos.close();
}
}
zipFile.close();
} catch (Exception e) {
e.printStackTrace();
}
}

public static void zip(File dir, File zip) throws Exception {
// 删除已存在的压缩文件
zip.delete();
// 压缩文件并对输出文件做CRC32校验
CheckedOutputStream cos = new CheckedOutputStream(new FileOutputStream(
zip), new CRC32());
ZipOutputStream zos = new ZipOutputStream(cos);
compress(dir, zos, "");
zos.flush();
zos.close();
}

private static void compress(File srcFile, ZipOutputStream zos,
String basePath) throws Exception {
if (srcFile.isDirectory()) {
compressDir(srcFile, zos, basePath);
} else {
compressFile(srcFile, zos, basePath);
}
}

private static void compressDir(File dir, ZipOutputStream zos,
String basePath) throws Exception {
File[] files = dir.listFiles();
// 文件夹为空,构建空目录
if (files.length < 1) {
ZipEntry entry = new ZipEntry(basePath + dir.getName() + "/");
zos.putNextEntry(entry);
zos.closeEntry();
}
// 递归压缩
for (File file : files) {
compress(file, zos, basePath + dir.getName() + "/");
}
}

private static void compressFile(File file, ZipOutputStream zos, String dir)
throws Exception {
// 当前文件路径
String dirName = dir + file.getName();
// 文件新名称拼接
String[] dirNameNew = dirName.split("/");
StringBuffer buffer = new StringBuffer();

if (dirNameNew.length > 1) {
for (int i = 1; i < dirNameNew.length; i++) {
buffer.append("/");
buffer.append(dirNameNew[i]);
}
} else {
buffer.append("/");
}
// 创建压缩文件并写入数据
ZipEntry entry = new ZipEntry(buffer.toString().substring(1));
zos.putNextEntry(entry);
BufferedInputStream bis = new BufferedInputStream(new FileInputStream(
file));
int count;
byte data[] = new byte[1024];
while ((count = bis.read(data, 0, 1024)) != -1) {
zos.write(data, 0, count);
}
bis.close();
zos.closeEntry();
}
}

AES对称加密工具类

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public class AES {
// 默认密码
public static final String DEFAULT_PWD = "abcdefghijklmnop";
//
private static final String algorithmStr = "AES/ECB/PKCS5Padding";

private static Cipher encryptCipher;
private static Cipher decryptCipher;

public static void init(String password) {
try {
// 创建加密对象,ECB模式,PKCS5Padding填充方式
encryptCipher = Cipher.getInstance(algorithmStr);
// 创建解密对象
decryptCipher = Cipher.getInstance(algorithmStr);
// 获取密码字节数组
byte[] keyStr = password.getBytes();
// 生成加密密钥
SecretKeySpec key = new SecretKeySpec(keyStr, "AES");
// 初始化加密对象
encryptCipher.init(Cipher.ENCRYPT_MODE, key);
// 初始化解密对象
decryptCipher.init(Cipher.DECRYPT_MODE, key);
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (NoSuchPaddingException e) {
e.printStackTrace();
} catch (InvalidKeyException e) {
e.printStackTrace();
}
}

/**
*
* @param srcAPKfile 源文件所在位置
* @param dstApkFile 目标文件
* @return 加密后的新dex 文件
* @throws Exception
*/
public static File encryptAPKFile(File srcAPKfile, File dstApkFile) throws Exception {
if (srcAPKfile == null) {
System.out.println("encryptAPKFile :srcAPKfile null");
return null;
}
// 解压源文件到目标文件夹
Zip.unZip(srcAPKfile, dstApkFile);
// 获得目标文件夹所有的dex
File[] dexFiles = dstApkFile.listFiles(new FilenameFilter() {
@Override
public boolean accept(File file, String s) {
return s.endsWith(".dex");
}
});

File mainDexFile = null;
byte[] mainDexData = null;
// 遍历所有的dex文件,找到并记录主dex文件并获得加密后的字节数组
for (File dexFile: dexFiles) {
// 获取dex的字节数组
byte[] buffer = Utils.getBytes(dexFile);
// 加密后的字节数组
byte[] encryptBytes = AES.encrypt(buffer);

if (dexFile.getName().endsWith("classes.dex")) {
mainDexData = encryptBytes;
mainDexFile = dexFile;
}
//用加密后的字节数组替换原来的数据
FileOutputStream fos = new FileOutputStream(dexFile);
fos.write(encryptBytes);
fos.flush();
fos.close();
}

// 返回主dex文件
return mainDexFile;
}

// 对字节数组加密返回
public static byte[] encrypt(byte[] content) {
try {
byte[] result = encryptCipher.doFinal(content);
return result;
} catch (IllegalBlockSizeException e) {
e.printStackTrace();
} catch (BadPaddingException e) {
e.printStackTrace();
}
return null;
}

// 字节数组解密返回
public static byte[] decrypt(byte[] content) {
try {
byte[] result = decryptCipher.doFinal(content);
return result;
} catch (IllegalBlockSizeException e) {
e.printStackTrace();
} catch (BadPaddingException e) {
e.printStackTrace();
}
return null;
}
}

dx转换工具类

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public class Dx {

public static File jar2Dex(File aarFile) throws IOException, InterruptedException {
// 创建临时文件夹
File fakeDex = new File(aarFile.getParent() + File.separator + "temp");
// 解压aar到临时文件夹下
Zip.unZip(aarFile, fakeDex);
// 过滤找到classes.jar
File[] files = fakeDex.listFiles(new FilenameFilter() {
@Override
public boolean accept(File file, String s) {
return s.equals("classes.jar");
}
});
// aar文件不存在抛异常
if (files == null || files.length <= 0) {
throw new RuntimeException("the aar is invalidate");
}
// 将classes.jar转classes.dex
File classes_jar = files[0];
// 创建classes.dex文件
File aarDex = new File(classes_jar.getParentFile(), "classes.dex");

//使用android tools里面的dx.bat,调windows下的命令
Dx.dxCommand(aarDex, classes_jar);
return aarDex;
}

public static void dxCommand(File aarDex, File classes_jar) throws IOException, InterruptedException {
Runtime runtime = Runtime.getRuntime();
Process process = runtime.exec("cmd.exe /C dx --dex --output=" + aarDex.getAbsolutePath() + " " +
classes_jar.getAbsolutePath());

try {
process.waitFor();
} catch (InterruptedException e) {
e.printStackTrace();
throw e;
}
// 转换失败,输出错误到文件并抛异常
if (process.exitValue() != 0) {
InputStream inputStream = process.getErrorStream();
int len;
byte[] buffer = new byte[2048];
ByteArrayOutputStream bos = new ByteArrayOutputStream();
while((len=inputStream.read(buffer)) != -1){
bos.write(buffer,0,len);
}
System.out.println(new String(bos.toByteArray(),"GBK"));
throw new RuntimeException("dx run failed");
}
process.destroy();
}
}

签名工具类

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import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;


public class Signature {
public static void signature(File unsignedApk, File signedApk) throws InterruptedException, IOException {
// 执行windows下的签名命令
String cmd[] = {"cmd.exe", "/C ","jarsigner", "-sigalg", "MD5withRSA",
"-digestalg", "SHA1",
"-keystore", "C:/Users/allen/.android/debug.keystore",
"-storepass", "android",
"-keypass", "android",
"-signedjar", signedApk.getAbsolutePath(),
unsignedApk.getAbsolutePath(),
"androiddebugkey"};
Process process = Runtime.getRuntime().exec(cmd);
System.out.println("start sign");
try {
int waitResult = process.waitFor();
System.out.println("waitResult: " + waitResult);
} catch (InterruptedException e) {
e.printStackTrace();
throw e;
}
System.out.println("process.exitValue() " + process.exitValue() );
// 执行失败,输出错误到文件并抛异常
if (process.exitValue() != 0) {
InputStream inputStream = process.getErrorStream();
int len;
byte[] buffer = new byte[2048];
ByteArrayOutputStream bos = new ByteArrayOutputStream();
while((len=inputStream.read(buffer)) != -1){
bos.write(buffer,0,len);
}
System.out.println(new String(bos.toByteArray(),"GBK"));
throw new RuntimeException("sign run failed");
}
System.out.println("finish signed");
process.destroy();
}
}

实现壳程序

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public class ShellApplication extends Application {
private static final String TAG = "ShellApplication";

public static String getPassword(){
return "abcdefghijklmnop";
}

@Override
protected void attachBaseContext(Context base) {
super.attachBaseContext(base);
// 初始化AES加密
AES.init(getPassword());
// 待解密文件路径data/data/包名/files/fake_apk/
File apkFile = new File(getApplicationInfo().sourceDir);
File unZipFile = getDir("fake_apk", MODE_PRIVATE);
// 待解密的文件目录data/data/包名/files/fake_apk/app
File app = new File(unZipFile, "app");
// 如果不存在待解密文件目录,解压apk
if (!app.exists()) {
Zip.unZip(apkFile, app);
// 过滤不为classes.dex的.dex文件,对读取的字节数组解密写出到文件
File[] files = app.listFiles();
for (File file : files) {
String name = file.getName();
if (name.equals("classes.dex")) {

} else if (name.endsWith(".dex")) {
try {
byte[] bytes = getBytes(file);
FileOutputStream fos = new FileOutputStream(file);
byte[] decrypt = AES.decrypt(bytes);
fos.write(decrypt);
fos.flush();
fos.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
// 获取待解密的文件目录.dex文件列表
List list = new ArrayList<>();
Log.d("FAKE", Arrays.toString(app.listFiles()));
for (File file : app.listFiles()) {
if (file.getName().endsWith(".dex")) {
list.add(file);
}
}

Log.d("FAKE", list.toString());
try {
V19.install(getClassLoader(), list, unZipFile);
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (NoSuchFieldException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
}

// 反射获取对象某个变量的值
private static Field findField(Object instance, String name) throws NoSuchFieldException {
Class clazz = instance.getClass();

while (clazz != null) {
try {
Field e = clazz.getDeclaredField(name);
if (!e.isAccessible()) {
e.setAccessible(true);
}

return e;
} catch (NoSuchFieldException var4) {
clazz = clazz.getSuperclass();
}
}

throw new NoSuchFieldException("Field " + name + " not found in " + instance.getClass());
}

// 反射获取对象的某个方法
private static Method findMethod(Object instance, String name, Class... parameterTypes)
throws NoSuchMethodException {
Class clazz = instance.getClass();
while (clazz != null) {
try {
Method e = clazz.getDeclaredMethod(name, parameterTypes);
if (!e.isAccessible()) {
e.setAccessible(true);
}

return e;
} catch (NoSuchMethodException var5) {
clazz = clazz.getSuperclass();
}
}
throw new NoSuchMethodException("Method " + name + " with parameters " + Arrays.asList
(parameterTypes) + " not found in " + instance.getClass());
}

// 扩展某个对象的某个变量数组
private static void expandFieldArray(Object instance, String fieldName, Object[]
extraElements) throws NoSuchFieldException, IllegalArgumentException,
IllegalAccessException {
Field jlrField = findField(instance, fieldName);
Object[] original = (Object[]) ((Object[]) jlrField.get(instance));
Object[] combined = (Object[]) ((Object[]) Array.newInstance(original.getClass()
.getComponentType(), original.length + extraElements.length));
System.arraycopy(original, 0, combined, 0, original.length);
System.arraycopy(extraElements, 0, combined, original.length, extraElements.length);
jlrField.set(instance, combined);
}

// 动态加载类
private static final class V19 {
private V19() {
}
private static void install(ClassLoader loader, List<File> additionalClassPathEntries,
File optimizedDirectory) throws IllegalArgumentException,
IllegalAccessException, NoSuchFieldException, InvocationTargetException,
NoSuchMethodException {
// 获取ClassLoader对象的pathList变量的值
Field pathListField = findField(loader, "pathList");
Object dexPathList = pathListField.get(loader);
ArrayList suppressedExceptions = new ArrayList();
Log.d(TAG, "Build.VERSION.SDK_INT " + Build.VERSION.SDK_INT);
// 根据当前SDK版本动态批量加载类
if (Build.VERSION.SDK_INT >= 23) {
expandFieldArray(dexPathList, "dexElements", makePathElements(dexPathList, new
ArrayList(additionalClassPathEntries), optimizedDirectory,
suppressedExceptions));
} else {
expandFieldArray(dexPathList, "dexElements", makeDexElements(dexPathList, new
ArrayList(additionalClassPathEntries), optimizedDirectory,
suppressedExceptions));
}
// 如果有异常,遍历打印
if (suppressedExceptions.size() > 0) {
Iterator suppressedExceptionsField = suppressedExceptions.iterator();

while (suppressedExceptionsField.hasNext()) {
IOException dexElementsSuppressedExceptions = (IOException)
suppressedExceptionsField.next();
Log.w("MultiDex", "Exception in makeDexElement",
dexElementsSuppressedExceptions);
}
// 获取dexElementsSuppressedExceptions变量的值
Field suppressedExceptionsField1 = findField(loader,
"dexElementsSuppressedExceptions");
IOException[] dexElementsSuppressedExceptions1 = (IOException[]) ((IOException[])
suppressedExceptionsField1.get(loader));
// 如果值为空,赋值为异常数组
if (dexElementsSuppressedExceptions1 == null) {
dexElementsSuppressedExceptions1 = (IOException[]) suppressedExceptions
.toArray(new IOException[suppressedExceptions.size()]);
} else {
// 否则扩展异常数组,合并dexElementsSuppressedExceptions并重新赋值
IOException[] combined = new IOException[suppressedExceptions.size() +
dexElementsSuppressedExceptions1.length];
suppressedExceptions.toArray(combined);
System.arraycopy(dexElementsSuppressedExceptions1, 0, combined,
suppressedExceptions.size(), dexElementsSuppressedExceptions1.length);
dexElementsSuppressedExceptions1 = combined;
}

suppressedExceptionsField1.set(loader, dexElementsSuppressedExceptions1);
}

}

// 调用dexPathList对象的makeDexElements方法
private static Object[] makeDexElements(Object dexPathList,
ArrayList<File> files, File
optimizedDirectory,
ArrayList<IOException> suppressedExceptions) throws
IllegalAccessException, InvocationTargetException, NoSuchMethodException {

Method makeDexElements = findMethod(dexPathList, "makeDexElements", new
Class[]{ArrayList.class, File.class, ArrayList.class});
return ((Object[]) makeDexElements.invoke(dexPathList, new Object[]{files,
optimizedDirectory, suppressedExceptions}));
}
}
// 调用dexPathList对象的makePathElements方法
private static Object[] makePathElements(
Object dexPathList, ArrayList<File> files, File optimizedDirectory,
ArrayList<IOException> suppressedExceptions)
throws IllegalAccessException, InvocationTargetException, NoSuchMethodException {
// 查找返回类型为List的makePathElements方法
Method makePathElements;
try {
makePathElements = findMethod(dexPathList, "makePathElements", List.class, File.class,
List.class);
} catch (NoSuchMethodException e) {
Log.e(TAG, "NoSuchMethodException: makePathElements(List,File,List) failure");
// 查找返回类型为ArrayList的makePathElements方法
try {
makePathElements = findMethod(dexPathList, "makePathElements", ArrayList.class, File.class, ArrayList.class);
} catch (NoSuchMethodException e1) {
Log.e(TAG, "NoSuchMethodException: makeDexElements(ArrayList,File,ArrayList) failure");
// 调用dexPathList对象的makeDexElements方法
try {
Log.e(TAG, "NoSuchMethodException: try use v19 instead");
return V19.makeDexElements(dexPathList, files, optimizedDirectory, suppressedExceptions);
} catch (NoSuchMethodException e2) {
Log.e(TAG, "NoSuchMethodException: makeDexElements(List,File,List) failure");
throw e2;
}
}
}
return (Object[]) makePathElements.invoke(dexPathList, files, optimizedDirectory, suppressedExceptions);
}

private byte[] getBytes(File file) throws Exception {
RandomAccessFile r = new RandomAccessFile(file, "r");
byte[] buffer = new byte[(int) r.length()];
r.readFully(buffer);
r.close();
return buffer;
}
}