事件 MotionEvent

点击和长按可能会同时发生，需要在长按的回调函数中返回true，就不会产生点击。谁处理事件谁就是消费者

如果view组件不处理事件，最后会让ontouchevent处理，它是备胎

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <com.atguigu.l06_event.MyImageView
        android:id="@+id/iv_touch_test"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/atguigu"
        android:layout_margin="10dp"/>

</LinearLayout>

public class MotionEventTestActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_touch);

        //得到MYimageView
        MyImageView iv_touch_test = (MyImageView) findViewById(R.id.iv_touch_test);
        //设置touch监听
        iv_touch_test.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                Log.e("TAG", "MYimageView Listener onTouch() "+event.getAction());

                return false;
            }
        });

    }

    @Override
    public boolean dispatchTouchEvent(MotionEvent ev) {
        Log.i("TAG", "Activity dispatchTouchEvent() "+ev.getAction());
        return super.dispatchTouchEvent(ev);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        Log.i("TAG", "Activity onTouchEvent() "+event.getAction());
        return super.onTouchEvent(event);
    }
}

public class MyImageView extends ImageView {

    public MyImageView(Context context, AttributeSet attrs) {
        super(context, attrs);
        Log.e("TAG", "MyImageView()");
    }

    @Override
    public boolean dispatchTouchEvent(MotionEvent event) {
        Log.e("TAG", "MyImageView dispatchTouchEvent() "+event.getAction());
        return super.dispatchTouchEvent(event);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        Log.e("TAG", "MyImageView onTouchEvent() "+event.getAction());
        return false;
        //return true;
    }
}

在屏幕上点击图片之后 执行顺序如下

处理：调用回调方法或监听。调用回调方法或监听返回true的那个才是消费的，如果事件被消费了就不会再向下传递

如下更改，事件到listner就结束了，就不会再继续往下传递

  iv_touch_test.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                Log.e("TAG", "MYimageView Listener onTouch() "+event.getAction());

                    return true;

            }
        });