@Override
    public void requestChildFocus(View child, View focused) {
        if (!mIsLayoutDirty) {
            scrollToChild(focused);
        } else {
            // The child may not be laid out yet, we can't compute the scroll yet
            mChildToScrollTo = focused;
        }
        super.requestChildFocus(child, focused);
    }
Compute the amount to scroll in the Y direction in order to get
a rectangle completely on the screen (or, if taller than the screen,
at least the first screen size chunk of it).

@param rect The rect.
@return The scroll delta.
app/src/main/java/home/smart/fly/animations/widget/NestedScrollView.java