@Override
	public void addFocusables(ArrayList<View> views, int direction) {
		getChildAt(mCurrentPage).addFocusables(views, direction);
		if (direction == View.FOCUS_LEFT) {
			if (mCurrentPage > 0) {
				getChildAt(mCurrentPage - 1).addFocusables(views, direction);
			}
		} else if (direction == View.FOCUS_RIGHT) {
			if (mCurrentPage < getChildCount() - 1) {
				getChildAt(mCurrentPage + 1).addFocusables(views, direction);
			}
		}
	}
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