Android按钮单击事件的五种实现方式

1. 匿名内部类作为事件监听器

   public class MainActivity extends Activity {
   
    private Button button;
   
       @Override
       protected void onCreate(Bundle savedInstanceState) {
           super.onCreate(savedInstanceState);
           setContentView(R.layout.activity_main);
           button = (Button) findViewById(R.id.button1);
           button.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                System.out.println("匿名内部类作为事件监听器");
            }
        });
   
       }
   
   }

2. 内部类作为事件监听器

   public class MainActivity extends Activity {
   
    private Button button;
   
       @Override
       protected void onCreate(Bundle savedInstanceState) {
           super.onCreate(savedInstanceState);
           setContentView(R.layout.activity_main);
           button = (Button) findViewById(R.id.button1);
           button.setOnClickListener(new ButtonOnClickListener());
       }
   
       class ButtonOnClickListener implements OnClickListener{
        @Override
        public void onClick(View v) {
            System.out.println("内部类作为事件监听器");
        }
       }
   
   }

3. Activity本身作为事件监听器

   public class MainActivity extends Activity implements OnClickListener{
   
    private Button button;
   
       @Override
       protected void onCreate(Bundle savedInstanceState) {
           super.onCreate(savedInstanceState);
           setContentView(R.layout.activity_main);
           button = (Button) findViewById(R.id.button1);
           button.setOnClickListener(this);
       }
   
       @Override
       public void onClick(View v) {
        System.out.println("Activity本身作为事件监听器");
       }
   
   }

4. 外部类作为事件监听器

   public class MainActivity extends Activity {
   
    private Button button;
   
       @Override
       protected void onCreate(Bundle savedInstanceState) {
           super.onCreate(savedInstanceState);
           setContentView(R.layout.activity_main);
           button = (Button) findViewById(R.id.button1);
           button.setOnClickListener(new ButtonOnClickListener());
       }
   
   }
   class ButtonOnClickListener implements OnClickListener {
   
    @Override
    public void onClick(View v) {
        System.out.println("外部类作为事件监听器");
    }
   
   }

5. 将事件处理方法直接绑定到标签

   <Button
               android:id="@ id/button1"
               android:layout_width="wrap_content"
               android:layout_height="wrap_content"
               android:text="点击事件"
               android:onClick="onClick" />

   public class MainActivity extends Activity {
   
       @Override
       protected void onCreate(Bundle savedInstanceState) {
           super.onCreate(savedInstanceState);
           setContentView(R.layout.activity_main);
       }
   
       public void onClick(View v){
        System.out.println("将事件处理方法直接绑定到标签");
       }
   
   }