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

Add multiple subpaths to your context, and draw with mode kCGPathEOFill. The Quartz 2D Programming Guide explains in more detail.

// Outer subpath: the whole rect
CGContextAddRect(context, rrect);

// Inner subpath: the area inside the whole rect    
CGContextMoveToPoint(context, minx, midy);
...
// Close the inner subpath
CGContextClosePath(context);

// Fill the path
CGContextDrawPath(context, kCGPathEOFill);