Android OnTouchListener

code:

 OnTouchListener touchListener=new OnTouchListener() {
            
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                System.out.println("mContent/2 touch:"+event);
                mGestureDetector.onTouchEvent(event);
                mPageIndicator.onTouchEvent(event);
                return true;
            }
        };

1.You may only get ActionDown in your activity,so if you want to get ActionMove and ActionUp ,make sure that your onTouch method return true.

2.You may get ActionCancel when you are dragging on it,which happens when a parent view takes over control of one of its children views.This will happen when parent container will intercept your touch event. Any ViewGroup that overridesViewGroup.onInterceptTouchEvent(MotionEvent) can do that (ScrollView or ListView for instance).

Proper way to deal with this is to call ViewParent.requestDisallowInterceptTouchEvent(boolean) method on your parent view once you think you need to keep the motion event.

Here's a quick example (attemptClaimDrag method is taken from android source code):

/**
 * Tries to claim the user's drag motion, and requests disallowing any
 * ancestors from stealing events in the drag.
 */

privatevoid attemptClaimDrag(){
   
//mParent = getParent();
   
if(mParent !=null){
        mParent
.requestDisallowInterceptTouchEvent(true);
   
}
}

@Override
publicboolean onTouchEvent(MotionEventevent){
   
if(event.getAction()==MotionEvent.ACTION_DOWN){
       
if(iWantToKeepThisEventForMyself(event)){
            attemptClaimDrag
();
       
}
       
//your logic here
   
}else{
       
//your logic here
   
}
}
 

 

原文地址:https://www.cnblogs.com/qiengo/p/2700471.html