通过接口的类和活动之间的通信

Question

我有MainActivity，希望通过接口与类进行通信。

public interface MyInterface(){ 
    public void doAction(); 
} 

在我的MainActivity我都会有这样的一段代码：

public class MainActivity extends AppCompatActivity implements MyInterface(){ 

    //....some more code here 

    @Override 
    public void doAction() { 
     //any code action here 
    } 

    //....some more code here 

} 

所以，现在，如果我有另一个类（不活动），我应该如何正确地作出阶级之间的联系---接口--- mainActivity？

public class ClassB { 

    private MyInterface myinterface; 
    //........ 

    //...... how to initialize the interface 
} 

我感到困惑如何在ClassB的

Answer 1

初始化和使用的接口在其他类的构造函数：ClassB，接受接口作为参数，传递的Activity参考，持有该对象在Activity。

像这样：

public class MainActivity extends AppCompatActivity implements MyInterface() 
{ 
    private ClassB ref; // Hold reference of ClassB directly in your activity or use another interface(would be a bit of an overkill) 

    @Override 
    public void onCreate (Bundle savedInstanceState) { 
     // call to super and other stuff.... 
     ref = new ClassB(this); // pass in your activity reference to the ClassB constructor! 
    } 

    @Override 
    public void doAction() { 
     // any code action here 
    } 
} 

public class ClassB 
{ 
    private MyInterface myinterface; 

    public ClassB(MyInterface interface) 
    { 
     myinterface = interface ; 
    } 

    // Ideally, your interface should be declared inside ClassB. 
    public interface MyInterface 
    { 
     // interface methods 
    } 
} 

仅供参考，这也是查看和演示班MVP设计模式是如何相互作用的。

Answer 2

public class MainActivity extends AppCompatActivity implements 
MyInterface 
{ 
    OnCreate() 
    { 
     ClassB classB= new ClassB(this); 
    } 
} 

public class ClassB 
{ 
    private MyInterface myinterface; 

    public ClassB(MyInterface myinterface) 
    { 
     this.myinterface=myinterface; 
    } 

    void anyEvent() // like user click 
    { 
     myinterface.doAction(); 
    } 
}