private void ApplyPreferedSize(Size preferedSize, Size panelSize)
{
_needBothScroll = false;
var needHorizontalScroll = HorizontalScroll.HasScroll;
var needVerticalScroll = VerticalScroll.UpdateLength(preferedSize.Height, null, panelSize.Height - (needHorizontalScroll ? HorizontalScroll.BarThickness : 0), panelSize.Width);
HorizontalScroll.UpdateLength(preferedSize.Width, null, panelSize.Width - (needVerticalScroll ? VerticalScroll.BarThickness : 0), panelSize.Height);
if (needHorizontalScroll != HorizontalScroll.HasScroll)
{
needHorizontalScroll = HorizontalScroll.HasScroll;
needVerticalScroll = VerticalScroll.UpdateLength(preferedSize.Height, null, panelSize.Height - (needHorizontalScroll ? HorizontalScroll.BarThickness : 0), panelSize.Width);
}
_needBothScroll = needVerticalScroll && needHorizontalScroll;
if (_needBothScroll)
{
_leftoverBar = new Rectangle(panelSize.Width - VerticalScroll.BarThickness, panelSize.Height - HorizontalScroll.BarThickness, VerticalScroll.BarThickness, HorizontalScroll.BarThickness);
}
}
protected void ComputeScrollbars(Size naturalSize, Size availableSize)
{
_needBothScroll = false;
var needHorizontalScroll = HorizontalScroll.HasScroll;
var needVerticalScroll = VerticalScroll.UpdateLength(naturalSize.Height, null, availableSize.Height - (needHorizontalScroll ? HorizontalScroll.BarThickness : 0), availableSize.Width);
HorizontalScroll.UpdateLength(naturalSize.Width, null, availableSize.Width - (needVerticalScroll ? VerticalScroll.BarThickness : 0), availableSize.Height);
if (needHorizontalScroll != HorizontalScroll.HasScroll)
{
needHorizontalScroll = HorizontalScroll.HasScroll;
needVerticalScroll = VerticalScroll.UpdateLength(naturalSize.Height, null, availableSize.Height - (needHorizontalScroll ? HorizontalScroll.BarThickness : 0), availableSize.Width);
}
// compute the "left over" rectangle on the bottom right between the 2 scrolls
_needBothScroll = needVerticalScroll && needHorizontalScroll;
if (_needBothScroll)
{
_leftoverBar = new Rectangle(ContentSurfaceWithScrolls.X + ContentSurfaceWithScrolls.Width - VerticalScroll.BarThickness, ContentSurfaceWithScrolls.Y + ContentSurfaceWithScrolls.Height - HorizontalScroll.BarThickness, VerticalScroll.BarThickness, HorizontalScroll.BarThickness);
}
ContentSurface = new Rectangle(ContentSurfaceWithScrolls.X, ContentSurfaceWithScrolls.Y, ContentSurfaceWithScrolls.Width - (needVerticalScroll ? VerticalScroll.BarThickness : 0), ContentSurfaceWithScrolls.Height - (needHorizontalScroll ? HorizontalScroll.BarThickness : 0));
}