<Button
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="@string/show_toast"
  android:onClick="showToast">
</Button>

/**
 * @description 显示toast提示信息
 * @author zhuyangxing 2013-11-22上午9:26:00
 * @param v
 */
public void showToast(View v){
  Toast.makeText(MainActivity.this, "这里是提示信息", Toast.LENGTH_SHORT).show();
}

<Button
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="@string/changeToRed"
  android:id="@+id/button2">
</Button>

@SuppressLint("SetJavaScriptEnabled")
@Override
protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  Button button2 = (Button) findViewById(R.id.button2);//获得句柄
  button2.setOnClickListener(new OnClickListener() {
    public void onClick(View v) {
      text.setBackgroundColor(Color.RED);
    }
  });
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.testevent);
    mText = (TextView) findViewById(R.id.text1);
    mButton1 = (Button) findViewById(R.id.button1);
    mButton1.setOnClickListener(this); // 设置监听的类
    mButton2 = (Button) findViewById(R.id.button2);
    mButton2.setOnClickListener(this); // 设置监听的类
}
public void onClick(View v) {
    Log.v(TAG, "onClick()");
    switch(v.getId()){ // 区分不同的控件
      case R.id.button1:
        mText.setBackgroundColor(Color.RED);
        break;
      case R.id.button2:
        mText.setBackgroundColor(Color.GREEN);
        break;
      default:
        Log.v(TAG, "other");
        break;
    }
}