Cut transparent hole in the shape of UIImage into UIView

Question

I have an UIView in which I want to create a hole in the shape of the content of a UIImageView, but I can't get it to work. I can, however, mask an UIView to the shape of the UIImage.

My code:

let doorsMaskBounds = CGRect(x: 0, y: 0, width: 111, height: 111)

// Background view
let doorsBgView = UIView(frame: doorsMaskBounds)
doorsBgView.center = navigationController.view.center
doorsBgView.backgroundColor = UIColor.yellow

vc.view.addSubview(doorsBgView)
vc.view.bringSubview(toFront: doorsBgView)

// Logo Mask
doorsBgView.layer.mask = CALayer()
doorsBgView.layer.mask?.contents = UIImage(named: "doors")!.cgImage
doorsBgView.layer.mask?.bounds = doorsMaskBounds
doorsBgView.layer.mask?.anchorPoint = CGPoint(x: 0.5, y: 0.5)
doorsBgView.layer.mask?.position = CGPoint(x: doorsBgView.frame.width / 2, y: doorsBgView.frame.height / 2)

which results into:

I know how to "cut" a hole into a UIView in form of a shape I draw myself, as explained here, I just can't seem to figure out how the get the shape of the UIImage and apply it as the cut.

A UIImage has exactly 1 shape: rectangular. Be more specific about what you mean. All not transparent areas? A color channel? Line detection? — vikingosegundo, Mar 09 '17 at 13:07
The UIImage png file has as two channels, white and alpha channel. It should consider the white channel. — Paul Peelen, Mar 09 '17 at 13:32
No, I did not since the contents of the image does not exceed the boundaries of the view and the `UIImage` scales the image, I did not expect I had to set it. — Paul Peelen, Mar 09 '17 at 14:48
I am also not sure, if it is needed. I just saw a code fragment where it was used. Can you provide the image you use for masking? — vikingosegundo, Mar 09 '17 at 15:00

Cut transparent hole in the shape of UIImage into UIView

0 Answers0