触摸[0] 触摸事件传递机制

【参考链接】

开发艺术探索

AndroidView 事件分发机制 源码解析 （上）http://blog.csdn.net/lmj623565791/article/details/38960443

AndroidViewGroup事件分发机制http://blog.csdn.net/lmj623565791/article/details/39102591

探究requestDisallowInterceptTouchEvent失效的原因http://blog.csdn.net/jiwangkailai02/article/details/46666147

 

1.      

涉及到的类和方法主要有

ViewGroup的     dispatchTouchEvent()、onInterceptTouchEvent()、onTouchEvent()

View的                dispatchTouchEvent()、onInterceptTouchEvent()、onTouchEvent()

一般来说，在自定义View/ViewGroup的时候，不修改dispatchTouchEvent()，只重写onInterceptTouchEvent()（不保留super调用）和onTouchEvent()（保留super调用，如果需要响应OnLongClickListener/OnClickListener的话）

 

2.      

如果设置了OnTouchListener，则会先执行OnTouchListener。并且只有OnTouchListener返回false才会再执行onTouchEvent()。

 

3.      

如果子View能够收到ACTION_DOWN但其OnTouchListener/onTouchEvent()返回了false，则其不会再收到后续的ACTION_MOVE、ACTION_UP等。

 

4.      

可以在子View/ViewGroup的OnTouchListener/onTouchEvent()的ACTION_DOWN中使用getParent().requestDisallowInterceptTouchEvent()来请求父ViewGroup不要中断传递后续的ACTION_MOVE、ACTION_UP等。（此时也不会执行父ViewGroup的onInterceptTouchEvent()）

注意这只有在子View/ViewGroup能够收到ACTION_DOWN的前提下才能起作用。

 

5、

只有能够执行到View的super.onTouchEvent()才能够触发onLongClickListener/onClickListener。

如果设置了onLongClickListener，在ACTION_DOWN超时后就会触发onLongClickListener。

只有当onLongClickListener返回false，在ACTION_UP后才会继续触发onClickListener。

 

可以使用如下的代码来修改验证

public class MyFrameLayout extends FrameLayout {

//    public static final intACTION_DOWN = 0;
//    public static finalint ACTION_UP = 1;
//    public static finalint ACTION_MOVE = 2;
//    public static finalint ACTION_CANCEL = 3;

    public static final String[] ACTIONS={"ACTION_DOWN", "ACTION_UP", "ACTION_MOVE", "ACTION_CANCEL"};

    public MyFrameLayout(Context context) {
       super(context);
       init();
    }

    public MyFrameLayout(Context context, AttributeSet attrs) {
       super(context, attrs);
       init();
    }

    public MyFrameLayout(Context context, AttributeSet attrs, int defStyle) {
       super(context, attrs, defStyle);
       init();
    }

    public void init(){

       setOnTouchListener(new OnTouchListener() {
           @Override
           public boolean onTouch(View view, MotionEvent motionEvent) {
               Log.e("shadowfaxghh", "MyFrameLayout OnTouchListener "+ACTIONS[motionEvent.getAction()]);
               return false;
           }
       });

       setOnLongClickListener(new OnLongClickListener() {
           @Override
           public boolean onLongClick(View view) {
               Log.e("shadowfaxghh", "MyFrameLayout onLongClick");
               return false;
           }
       });

       setOnClickListener(new OnClickListener() {
           @Override
           public void onClick(View view) {
               Log.e("shadowfaxghh", "MyFrameLayout onClick");
           }
       });

    }

    @Override
    public boolean dispatchTouchEvent(MotionEvent ev) {
       Log.e("shadowfaxghh", "MyFrameLayout dispatchTouchEvent "+ACTIONS[ev.getAction()]);
       return super.dispatchTouchEvent(ev);
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
       Log.e("shadowfaxghh", "MyFrameLayout onInterceptTouchEvent "+ACTIONS[ev.getAction()]);

//       return super.onInterceptTouchEvent(ev);
//        return false;
       switch (ev.getAction()){
           case MotionEvent.ACTION_DOWN:
               return false;
           default:
               return true;
       }

    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
       Log.e("shadowfaxghh", "MyFrameLayout onTouchEvent "+ACTIONS[event.getAction()]);

       super.onTouchEvent(event);//for onLongClick/onClick

       return true;
    }
}

 

public class MyTextView extends TextView {

    public static final String[] ACTIONS={"ACTION_DOWN", "ACTION_UP", "ACTION_MOVE", "ACTION_CANCEL"};

    public MyTextView(Context context) {
       super(context);
       init();
    }

    public MyTextView(Context context, AttributeSet attrs) {
       super(context, attrs);
       init();
    }

    public MyTextView(Context context, AttributeSet attrs, int defStyle) {
       super(context, attrs, defStyle);
       init();
    }

    public void init(){

       setOnTouchListener(new OnTouchListener() {
           @Override
           public boolean onTouch(View view, MotionEvent motionEvent) {
               Log.e("shadowfaxghh", "MyTextView OnTouchListener "+ACTIONS[motionEvent.getAction()]);
               return false;
           }
       });

        setOnLongClickListener(new OnLongClickListener() {
           @Override
           public boolean onLongClick(View view) {
               Log.e("shadowfaxghh", "MyTextView onLongClick");
               return false;
           }
       });

       setOnClickListener(new OnClickListener() {
           @Override
           public void onClick(View view) {
               Log.e("shadowfaxghh", "MyTextView onClick");
           }
       });
    }

    @Override
    public boolean dispatchTouchEvent(MotionEvent ev) {
       Log.e("shadowfaxghh", "MyTextView dispatchTouchEvent");
       return super.dispatchTouchEvent(ev);
    }

//    @Override
//    public booleanonInterceptTouchEvent(MotionEvent ev) {
//
//       Log.e("shadowfaxghh", "MyTextViewonInterceptTouchEvent");
//
////       return super.onInterceptTouchEvent(ev);
//       return false;
//    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
       Log.e("shadowfaxghh", "MyTextView onTouchEvent "+ACTIONS[event.getAction()]);

       super.onTouchEvent(event);//for onLongClick/onClick

       switch(event.getAction()){
           case MotionEvent.ACTION_DOWN:
               getParent().requestDisallowInterceptTouchEvent(true);
               break;
           default:
               break;
       }

       return true;
    }
}