@Override
	protected void onLayout(boolean changed, int left, int top, int right,
			int bottom) {
		measuredHeight = 0;

		final int count = getChildCount();
		int height;
		for (int i = 0; i < count; i++) {
			final View child = getChildAt(i);
			if (child.getVisibility() != View.GONE) {
				height = pageHeight
						* (int) Math.ceil((double) child.getMeasuredHeight()
								/ (double) pageHeight);
				height = Math.max(pageHeight, height);
				child.layout(0, measuredHeight, right - left, measuredHeight
						+ height);
				measuredHeight += height;
			}
		}
	}
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