public void RefreshVisuals()
{
var height = ((Shell)Window.Current.Content).ActualHeight;
var width = ((Shell)Window.Current.Content).ActualWidth;
var ttv = ChatBubble.TransformToVisual(Window.Current.Content);
Point screenCoords = ttv.TransformPoint(new Point(0, 0));
var controlWidth = ChatBubble.Width;
var controlHeight = ChatBubble.Height;
BgColor.Width = width;
BgColor.Height = height;
var marg = BgColor.Margin;
marg.Left = screenCoords.X - width;
marg.Top = screenCoords.Y - height;
marg.Right = screenCoords.X - width - controlWidth;
marg.Bottom = screenCoords.Y - height - controlHeight;
BgColor.Margin = marg;
}