private boolean canScroll() {
        View child = getChildAt(0);
        if (child != null) {
            int childHeight = child.getHeight();
            return getHeight() < childHeight + getPaddingTop() + getPaddingBottom();
        }
        return false;
    }
@return Returns true this ScrollView can be scrolled
app/src/main/java/home/smart/fly/animations/widget/NestedScrollView.java