How to get CGFloat value from NSLayoutConstraints?

Question

I am working on screen where I want to make this profile view circular. But I am not getting height or width from imageView.frame.height to use it in layer.cornerRadius. Please help me. Thanks.

Here is the code for reference.

private func addImageView() {
        topView.addSubview(profilePicView)

        NSLayoutConstraint.activate([
            profilePicView.centerXAnchor.constraint(equalTo: topView.centerXAnchor),
            profilePicView.widthAnchor.constraint(equalTo: topView.heightAnchor, multiplier: 0.3)
            ])

        profilePicViewTopAnchor = profilePicView.topAnchor.constraint(equalTo: view.topAnchor, constant: 64)
        profilePicViewTopAnchor?.isActive = true

        profilePicViewHeightAnchor = profilePicView.heightAnchor.constraint(equalTo: topView.heightAnchor, multiplier: 0.3)
        profilePicViewHeightAnchor?.isActive = true
    }

And I am trying to get values as,

override func viewDidLayoutSubviews() {
        super.viewDidLayoutSubviews()
        print((profilePicViewHeightAnchor?.constant)!)
        profilePicView.layer.cornerRadius = (profilePicViewHeightAnchor?.constant)! / 2
        profilePicView.clipsToBounds = true

    }

SOLVED

After everyones help I got this solution which works perfectly fine for me,

override func viewDidLayoutSubviews() {
        super.viewDidLayoutSubviews()

        let radius = redView.frame.height * 0.3
        profilePicView.layer.cornerRadius = radius / 2
        profilePicView.clipsToBounds = true

        self.view.layoutIfNeeded()

    }

Thanks to all you guys. Really appreciated the help.

Answer 1

This must be because the time you are accessing the frame for imageView, the layout constraints are not laid out by the autolayout. So, If your imageView is inside a UIViewController class then you should override the below method and then access the width and height.

override func viewDidLayoutSubviews() {
    super.viewDidLayoutSubviews()

    print(imageView.frame.height)
}

If imageView is inside a custom view then you can override the below method and then access the frame,

override func layoutSubviews() {
    super.layoutSubviews()

    print(imageView.frame.height)
}