解决ScrollView嵌套viewpager滑动事件冲突问题

重写ScrollView

第一种方案能解决viewpager的滑动问题，但是scrollView有时会滑不动

public class VerticalScrollView extends ScrollView {

    private GestureDetector mGestureDetector;

    public VerticalScrollView(Context context, AttributeSet attrs){
        super(context, attrs);
        mGestureDetector = new GestureDetector(context, new YScrollDetector());
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        return super.onInterceptTouchEvent(ev) && mGestureDetector.onTouchEvent(ev);
    }

    class YScrollDetector extends SimpleOnGestureListener {

        @Override
        public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
            /**
             * if we're scrolling more closer to x direction, return false, let subview to process it
             */
            HBLog.i("VerticalScrollView", distanceY+"----"+distanceX);
            return (Math.abs(distanceY) > Math.abs(distanceX));
        }
    }

}

第二种方案能够解决上面的问题

public class VerticalScrollView extends ScrollView {

    private float xDistance, yDistance, xLast, yLast; 

    public VerticalScrollView(Context context) {
        super(context);
    } 

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

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

    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        switch (ev.getAction()) {
        case MotionEvent.ACTION_DOWN:
            xDistance = yDistance = 0f;
            xLast = ev.getX();
            yLast = ev.getY();
            break;
        case MotionEvent.ACTION_MOVE:
            final float curX = ev.getX();
            final float curY = ev.getY(); 

            xDistance += Math.abs(curX - xLast);
            yDistance += Math.abs(curY - yLast);
            xLast = curX;
            yLast = curY; 

            if (xDistance > yDistance) {
                return false;
            }
        }
        return super.onInterceptTouchEvent(ev);
    }

}