淺談onTouch先執行,還是onClick執行(詳解)

mTestButton.setOnClickListener(new View.OnClickListener() {  
      @Override 
      public void onClick(View view) {  
        Log.d(TAG, "onClick execute");  
      }  
});  
mTestButton.setOnTouchListener(new View.OnTouchListener() {  
      @Override 
      public boolean onTouch(View view, MotionEvent motionEvent) {  
        Log.d(TAG, "onTouch execute, action event " + motionEvent.getAction());  
        return false;  
      }  
});  

public boolean dispatchTouchEvent(MotionEvent event) {  
  if (mOnTouchListener != null && (mViewFlags & ENABLED_MASK) == ENABLED &&  
      mOnTouchListener.onTouch(this, event)) {  
    return true;  
  }  
  return onTouchEvent(event);  
}  

public boolean onTouchEvent(MotionEvent event) { 
  final int viewFlags = mViewFlags; 
  if ((viewFlags & ENABLED_MASK) == DISABLED) { 
    // A disabled view that is clickable still consumes the touch 
    // events, it just doesn't respond to them. 
    return (((viewFlags & CLICKABLE) == CLICKABLE || 
        (viewFlags & LONG_CLICKABLE) == LONG_CLICKABLE)); 
  } 
  if (mTouchDelegate != null) { 
    if (mTouchDelegate.onTouchEvent(event)) { 
      return true; 
    } 
  } 
  if (((viewFlags & CLICKABLE) == CLICKABLE || 
      (viewFlags & LONG_CLICKABLE) == LONG_CLICKABLE)) { 
    switch (event.getAction()) { 
      case MotionEvent.ACTION_UP: 
        boolean prepressed = (mPrivateFlags & PREPRESSED) != 0; 
        if ((mPrivateFlags & PRESSED) != 0 || prepressed) { 
          // take focus if we don't have it already and we should in 
          // touch mode. 
          boolean focusTaken = false; 
          if (isFocusable() && isFocusableInTouchMode() && !isFocused()) { 
            focusTaken = requestFocus(); 
          } 
          if (!mHasPerformedLongPress) { 
            // This is a tap, so remove the longpress check 
            removeLongPressCallback(); 
            // Only perform take click actions if we were in the pressed state 
            if (!focusTaken) { 
              // Use a Runnable and post this rather than calling 
              // performClick directly. This lets other visual state 
              // of the view update before click actions start. 
              if (mPerformClick == null) { 
                mPerformClick = new PerformClick(); 
              } 
              if (!post(mPerformClick)) { 
                performClick(); 
              } 
            } 
          } 
          if (mUnsetPressedState == null) { 
            mUnsetPressedState = new UnsetPressedState(); 
          } 
          if (prepressed) { 
            mPrivateFlags |= PRESSED; 
            refreshDrawableState(); 
            postDelayed(mUnsetPressedState, 
                ViewConfiguration.getPressedStateDuration()); 
          } else if (!post(mUnsetPressedState)) { 
            // If the post failed, unpress right now 
            mUnsetPressedState.run(); 
          } 
          removeTapCallback(); 
        } 
        break; 
      case MotionEvent.ACTION_DOWN: 
        if (mPendingCheckForTap == null) { 
          mPendingCheckForTap = new CheckForTap(); 
        } 
        mPrivateFlags |= PREPRESSED; 
        mHasPerformedLongPress = false; 
        postDelayed(mPendingCheckForTap, ViewConfiguration.getTapTimeout()); 
        break; 
      case MotionEvent.ACTION_CANCEL: 
        mPrivateFlags &= ~PRESSED; 
        refreshDrawableState(); 
        removeTapCallback(); 
        break; 
      case MotionEvent.ACTION_MOVE: 
        final int x = (int) event.getX(); 
        final int y = (int) event.getY(); 
        // Be lenient about moving outside of buttons 
        int slop = mTouchSlop; 
        if ((x < 0 - slop) || (x >= getWidth() + slop) || 
            (y < 0 - slop) || (y >= getHeight() + slop)) { 
          // Outside button 
          removeTapCallback(); 
          if ((mPrivateFlags & PRESSED) != 0) { 
            // Remove any future long press/tap checks 
            removeLongPressCallback(); 
            // Need to switch from pressed to not pressed 
            mPrivateFlags &= ~PRESSED; 
            refreshDrawableState(); 
          } 
        } 
        break; 
    } 
    return true; 
  } 
  return false; 
}

public boolean performClick() {  
  sendAccessibilityEvent(AccessibilityEvent.TYPE_VIEW_CLICKED);  
  if (mOnClickListener != null) {  
    playSoundEffect(SoundEffectConstants.CLICK);  
    mOnClickListener.onClick(this);  
    return true;  
  }  
  return false;  
} 

public void setOnClickListener(OnClickListener l) {  
  if (!isClickable()) {  
    setClickable(true);  
  }  
  mOnClickListener = l;  
}