How to get x and y position of UIImage in UIImageView?

Question

I want to get original x and y position of UIImage when we set it in UIImageView with scaleAspectFill.

As we know in scaleAspectFill, some of the portion is clipped. So as per my requirement I want to get x and y value (it may be - value I don't know.).

Here is the original image from gallery

Now I am setting this above image to my app view.

So as above situation, I want to get it's hidden x, y position of image which are clipped.

Can any one tell how to get it?

Answer 1

Use following extension

extension UIImageView {

    var imageRect: CGRect {
        guard let imageSize = self.image?.size else { return self.frame }

        let scale = UIScreen.main.scale

        let imageWidth = (imageSize.width / scale).rounded()
        let frameWidth = self.frame.width.rounded()

        let imageHeight = (imageSize.height / scale).rounded()
        let frameHeight = self.frame.height.rounded()

        let ratio = max(frameWidth / imageWidth, frameHeight / imageHeight)
        let newSize = CGSize(width: imageWidth * ratio, height: imageHeight * ratio)
        let newOrigin = CGPoint(x: self.center.x - (newSize.width / 2), y: self.center.y - (newSize.height / 2))
        return CGRect(origin: newOrigin, size: newSize)
    }

}

Usage

let rect = imageView.imageRect
print(rect)

UI Test

let testView = UIView(frame: rect)
testView.backgroundColor = UIColor.red.withAlphaComponent(0.5)
imageView.superview?.addSubview(testView)