private static void PaintSingleBar(ICanvas canvas, float x1, float y1, float x2, float y2, float size) { canvas.BeginPath(); canvas.MoveTo(x1, y1); canvas.LineTo(x2, y2); canvas.LineTo(x2, y2 + size); canvas.LineTo(x1, y1 + size); canvas.ClosePath(); canvas.Fill(); }