Android buttion 的四种事件

XML文件如下:

<Button
    android:id="@+id/button1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Button1" />
 
  <Button
    android:id="@+id/button2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Button2" />

1. 匿名内部类

public class TestButtonActivity extends Activity {
 
  Button btn1, btn2;
  Toast tst;
 
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_test_button);
 
    btn1 = (Button) findViewById(R.id.button1);
    btn2 = (Button) findViewById(R.id.button2);
 
    btn1.setOnClickListener(new OnClickListener() {
 
      @Override
      public void onClick(View v) {
        // TODO Auto-generated method stub
        Toast tst = Toast.makeText(TestButtonActivity.this, "111111111", Toast.LENGTH_SHORT);
        tst.show();
 
      }
    });
 
    btn2.setOnClickListener(new OnClickListener() {
 
      @Override
      public void onClick(View v) {
        // TODO Auto-generated method stub
        Toast tst = Toast.makeText(TestButtonActivity.this, "222222222", Toast.LENGTH_SHORT);
        tst.show();
      }
    });
  }
}

2.自定义单击事件监听类

public class TestButtonActivity extends Activity {
 
  Button btn1, btn2;
  Toast tst;
 
  class MyClickListener implements OnClickListener {
 
    @Override
    public void onClick(View v) {
      // TODO Auto-generated method stub
      switch (v.getId()) {
      case R.id.button1:
        tst = Toast.makeText(TestButtonActivity.this, "111111111", Toast.LENGTH_SHORT);
        tst.show();
        break;
      case R.id.button2:
        tst = Toast.makeText(TestButtonActivity.this, "222222222", Toast.LENGTH_SHORT);
        tst.show();
        break;
      default:
        break;
      }
    }
  }
 
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_test_button);
 
    btn1 = (Button) findViewById(R.id.button1);
    btn2 = (Button) findViewById(R.id.button2);
 
    btn1.setOnClickListener(new MyClickListener());
    btn2.setOnClickListener(new MyClickListener());
  }
}

3.Activity继承View.OnClickListener，由Activity实现OnClick(View view)方法，在OnClick(View view)方法中用switch-case对不同id代表的button进行相应的处理

public class TestButtonActivity extends Activity implements OnClickListener {
 
  Button btn1, btn2;
  Toast tst;
 
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_test_button);
 
    btn1 = (Button) findViewById(R.id.button1);
    btn2 = (Button) findViewById(R.id.button2);
 
    btn1.setOnClickListener(this);
    btn2.setOnClickListener(this);
  }
 
  @Override
  public void onClick(View v) {
    // TODO Auto-generated method stub
    switch (v.getId()) {
    case R.id.button1:
      tst = Toast.makeText(this, "111111111", Toast.LENGTH_SHORT);
      tst.show();
      break;
    case R.id.button2:
      tst = Toast.makeText(this, "222222222", Toast.LENGTH_SHORT);
      tst.show();
      break;
    default:
      break;
    }
  }
}

4.最后一种是我今天看到的一种写法，在XML文件中“显示指定按钮的onClick属性，这样点击按钮时会利用反射的方式调用对应Activity中的click()方法”

public class TestButtonActivity extends Activity {
 
  Button btn1, btn2;
  Toast tst;
 
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_test_button);
  }
 
  // 注意 这里没有 @Override 标签
  public void onClick(View v) {
    // TODO Auto-generated method stub
    switch (v.getId()) {
    case R.id.button1:
      tst = Toast.makeText(this, "111111111", Toast.LENGTH_SHORT);
      tst.show();
      break;
    case R.id.button2:
      tst = Toast.makeText(this, "222222222", Toast.LENGTH_SHORT);
      tst.show();
      break;
    default:
      break;
    }
  }
}