android-实现监听器的三种方法

public class Test extends Activity{
    Button btn;
    public void onCreate(Bundle savedInstanceState){
    
    super.onCreate(savedInstanceState);
    setContentView(R,layout.main);

    ///给按钮添加监听器
    MyOnClickListener listener=new MyOnClickListener();
    btn.setOnClickListener(listener);
   }
    ///给出监听器类的定义
    class MyOnClickListener implements OnClickListener{
    @Override
    public void onClick(View arg0){
          Toast.makeTest......show();    
     }
   }
}

public class Test extends Activity {
Button btn;
public void onCreate(Bundle savedInstanceState ){
    super.onCreate(savedInstanceState );
    setContentView (R. layout.main );
    
    //匿名内部类写法
    btn.setOnClickListener (new OnClickListener (){
        @Override
         public void onClic(View v ){
            Toast .makeTest....show();
         }
    });
}

}

public class Test extends Activity implements OnClickListener{
Button btn;
public void onCreate(Bundle savedInstanceState ){
    super.onCreate(savedInstanceState );
    setContentView (R. layout.main );
    
    btn.setOnClickListener (this);
}
    //////直接覆盖 onClick方法就可以
    @Override
    public void onClick (View v){
        Toast .makeText( ...).show ();
    }
}