UIView drawRect: Draw the inverted pixels, make a hole, a window, negative space

Question

With the code below I am drawing a rounded rectangle. It draws a nice solid light gray filled rounded rectangle (at the size of \"self\"). I actually want to draw the pixel

Answer 1

Another approach: use UICreateGraphicsContextWithOptions(size, NO, 0) to make a bitmap. Draw the rectangle into the bitmap. Switch to the erasure blend mode:

CGContextSetBlendMode(con, kCGBlendModeClear);

Now draw the ellipse path and fill it. The result is a rectangle with a transparent elliptical hole. Now close out the image graphics context and draw the image into your original context.