Core Graphics, how to draw a Rectangle with an ellipse transparency hole?

Question

I am trying to draw a 320x480 rectangle that is hollowed by a ellipse. Imagine drawing a filled rectangle, over the rectangle an filled ellipse, and remove the ellipse from

Answer 1

This is off the top of my head, but...

CGPathRef cutoutRect = CGPathCreateMutable();       
CGPathAddRect(cutoutRect, NULL, rect);
CGPathAddEllipseInRect(cutoutRect, NULL, ellipseRect);

CGContextAddPath(context, cutoutRect);  
CGContextSetRGBFillColor(context, 1.0, 1.0, 0.0, 1.0);
CGContextFillPath(context);

You may actually need to use CGContextEOFillPath, I can never keep them straight. The CGContextClip-type functions should be used before drawing rather than after, but they're probably not necessary in this case.

That said, you shouldn't be doing this in a -drawRect: implementation, but the path should be set on a CAShapeLayer which is a sublayer of this view, or its only layer, or, indeed, a layer which is used instead of this view if possible.

Also note that the rectangle passed into drawRect: may be only part of the whole view, so your code will have some pretty weird results as-is. Did you mean self.bounds?