Swift UIImage全屏

Question

I have the UIImage like so:

let imageView = UIImageView(image: image!)

imageView.contentMode = .scaleToFill

self.view.addSubview(imageView)

What I am trying to do it make the image full width of the screen, I have tried scaleToFill, scaleAspectFit and scaleAspectFill neither of them do anything...what am I doing wrong?

Here is my full code:

getLandGradingImage(image: imageData!) { result in
    let image = UIImage(data: result)

    if image != nil {
        let imageView = UIImageView(image: image!)

        imageView.contentMode = .scaleAspectFit

        //Add Image to view
        self.view.addSubview(imageView)
    } else {
        self.customAlert(title: "Error", message: "Unable to get images")
    }

}

Answer 1

let imageView = UIImageView(image: image!)
imageView.contentMode = .scaleAspectFill
imageView.frame = self.view.bounds
imageView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
self.view.addSubview(imageView)

Answer 2

You have to make your UIImageView frame the size of the area you want to fill. You can do this by setting the frame explicitly or using auto-layout (recommended).

method 1:

let imageView = UIImageView(image: image!)
imageView.frame = self.view.frame;
imageView.contentMode = .scaleAspectFit
//Add Image to view
self.view.addSubview(imageView)

method 2:

let imageView = UIImageView(image: image!)
imageView.contentMode = .scaleAspectFit
//Add Image to view
self.view.addSubview(imageView)
self.view.translatesAutoresizingMaskIntoConstraints = false  

self.view.addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "H:|-0-[subview]-0-|", options: .directionLeadingToTrailing, metrics: nil, views: ["subview": imageView]))
self.view.addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "V:|-0-[subview]-0-|", options: .directionLeadingToTrailing, metrics: nil, views: ["subview": imageView]))

Answer 3

You want to manipulate the frame of the UIImageView and not the contentMode.

Try this:

let imageView = UIImageView(image: image!)

imageView.frame = self.view.frame
imageView.contentMode = .scaleToFill

self.view.addSubview(imageView)