@Override
	public boolean requestChildRectangleOnScreen(View child, Rect rectangle,
			boolean immediate) {
		int screen = indexOfChild(child);
		if (screen != mCurrentPage || !mScroller.isFinished()) {
			return true;
		}
		return false;
	}
Gets the value that getScrollX() should return if the specified page is
the current page (and no other scrolling is occurring). Use this to pass
a value to scrollTo(), for example.

@param whichPage
@return
app/src/main/java/pro/alexzaitsev/freepager/library/view/core/VerticalPager.java