public static UIImage image(this Tool tool, Color color) { switch (tool) { case Tool.Callout: return UIImage.FromBundle("i_tool_annotation"); case Tool.Marker: return UIImage.FromBundle("i_tool_marker"); case Tool.Arrow: return UIImage.FromBundle("i_tool_arrow"); case Tool.Circle: return UIImage.FromBundle("i_tool_circle"); case Tool.Square: return UIImage.FromBundle("i_tool_square"); case Tool.Color: return color.colorImage(); default: return null; } }