Image size error while rendering UIView to UIImage - ios

Question

I would like to convert two images into one image with custom design.
The expected image is a snapshot of my UICollectionViewCell, not a UIImage actually.
I copied the layout codes from my custom UICVCell.swift file and tried to render the view into UIImage, but the result image is what you can see below.
I searched through a lot of questions in SOF, but most of it was about 'How you can render a UIView into a UIImage.'
I've tried drawing too, but had the same messed up result.
Can anybody tell me what's the problem?
I would really appreciate your help, it's my first question in SOF.
I might cry in a minute or two, literally...
class ViewController: UIViewController {
private var imageView: UIImageView = {
let iv = UIImageView()
iv.contentMode = .scaleAspectFit
iv.clipsToBounds = true
return iv
}()
func createBubbleImage(images: [UIImage?]) -> UIImage? {
switch images.count {
case 1:
return images[0]
case 2:
let newView = UIView(frame: .init(x: 0, y: 0, width: 300, height: 300))
let size = newView.frame.width
let iv0 = UIImageView(image: images[0])
iv0.contentMode = .scaleAspectFit
iv0.clipsToBounds = true
let iv1 = UIImageView(image: images[1])
iv1.contentMode = .scaleAspectFit
iv1.clipsToBounds = true
newView.addSubview(iv0)
iv0.anchor(top: newView.topAnchor, left: newView.leftAnchor, paddingTop: size * 0.04, paddingLeft: size * 0.04, width: size * 0.56, height: size * 0.56)
newView.addSubview(iv1)
iv1.anchor(bottom: newView.bottomAnchor, right: newView.rightAnchor, paddingBottom: size * 0.04, paddingRight: size * 0.04, width: size * 0.56, height: size * 0.56)
iv0.layer.cornerRadius = size * 0.28
iv1.layer.cornerRadius = size * 0.28
let renderer = UIGraphicsImageRenderer(bounds: newView.bounds)
return renderer.image { ctx in
newView.layer.render(in: ctx.cgContext)
}
default:
return UIImage(named: "logo")
}
}
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .white
view.addSubview(imageView)
imageView.center(inView: view)
imageView.setDimensions(width: 300, height: 300)
imageView.image = createBubbleImage(images: [UIImage(named: "0"), UIImage(named: "1")])
}
}
Expected Image
Result Image

Answer 1

Do the following:
Remove the code lines that have the anchor method.
Initiate the iv0 and iv1 with UIImageView(frame: ...)
Add iv0.image = images[0] and iv1.image = images[1]
I also increased the radius a little bit because in my test device the images were not completely circular.
The code should look like this:
func createBubbleImage(images: [UIImage?]) -> UIImage? {
switch images.count {
case 1:
return images[0]
case 2:
let newView = UIView(frame: .init(x: 0, y: 0, width: 300, height: 300))
let size = newView.frame.width
let iv0 = UIImageView(frame: .init(x: 0, y: 0, width: 200, height: 200))
iv0.image = images[0]
iv0.contentMode = .scaleAspectFit
iv0.clipsToBounds = true
let iv1 = UIImageView(frame: .init(x: 100, y: 100, width: 200, height: 200))
iv1.image = images[1]
iv1.contentMode = .scaleAspectFit
iv1.clipsToBounds = true
newView.addSubview(iv0)
newView.addSubview(iv1)
iv0.layer.cornerRadius = size * 0.35
iv1.layer.cornerRadius = size * 0.35
let renderer = UIGraphicsImageRenderer(bounds: newView.bounds)
return renderer.image { ctx in
newView.layer.render(in: ctx.cgContext)
}
default:
return UIImage(named: "logo")
}
}
With it, the result is the following:
I had to take a screenshot from your "expected image", that's why the images look like zoomed in. You can play with the UIImageView(frame: ...) part to adjust the two images as you want (I didn't played enough to avoid that cut in the edges, but it is possible with the right measures).
Remark: the x and y values in the UIImageView frame are the horizontal and vertical distances from the top-left corner of newView to the top-left corner of your UIImageView, respectively.