ScrollView: Pass touch events to children

Question

I made a "joystick" out of an ImageView. It is inside a ScrollView.

It works without the ScrollView but inside the ScrollView it does not receive TouchEvents for vertical movement.

How can I stop the ScrollView from blocking the touch event?

Answer 1

I found a solution here.

I created a custom ScrollView class that has a boolean indicating whether it is locked. The onInterceptTouchEvent method is overridden:

@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
    if (!mScrollable) return false;
    return super.onInterceptTouchEvent(ev);
}

When the joystick is touched (ACTION_DOWN), the custom ScrollView is locked. At the ATCTION_UP event it is unlocked.