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iOS Introduction to Auto Layout in iOS Auto Layout in Code Using Layout Anchors

Connor Crawford
Connor Crawford
6,405 Points
Posted by Connor Crawford
Connor Crawford
6,405 Points

Error saying that type UIView has no member layoutMarginsGuide when pinning to left margin using anchor API

I am trying to pin the green view to the left margin using anchor API's but when I do I get an error saying the type UIView has no member layoutMarginsGuide but when I put it in Xcode there is no error and it compiles fine. Why is workspaces giving me an error saying it does not recognize the member. My code is attached

layout.swift 
class MyViewController: UIViewController {

    let blueView = UIView()
    let greenView = UIView()

    override func viewDidLoad() {
        super.viewDidLoad()
        view.addSubview(greenView)
        view.addSubview(blueView)
    }

    override func viewWillLayoutSubviews() {
        super.viewWillLayoutSubviews()
        blueView.translatesAutoresizingMaskIntoConstraints = false
        greenView.translatesAutoresizingMaskIntoConstraints = false

        NSLayoutConstraint.activateConstraints([
            NSLayoutConstraint(item: blueView, attribute: .Height, relatedBy: .Equal, toItem: nil, attribute: .NotAnAttribute, multiplier: 1.0, constant: 100.0),
            NSLayoutConstraint(item: blueView, attribute: .Width, relatedBy: .Equal, toItem: nil, attribute: .NotAnAttribute, multiplier: 1.0, constant: 150.0),
            NSLayoutConstraint(item: blueView, attribute: .Left, relatedBy: .Equal, toItem: view, attribute: .LeftMargin, multiplier: 1.0, constant: 8.0),
            NSLayoutConstraint(item: blueView, attribute: .Top, relatedBy: .Equal, toItem: self.topLayoutGuide, attribute: .Bottom, multiplier: 1.0, constant: 8.0),
            NSLayoutConstraint(item: blueView, attribute: .Right, relatedBy: .Equal, toItem: view, attribute: .RightMargin, multiplier: 1.0, constant: -8.0)
        ])

        // Add constraint code below
         NSLayoutConstraint.activateConstraints([greenView.topAnchor.constraintEqualToAnchor(blueView.bottomAnchor, constant: 8.0),
            greenView.leadingAnchor.constraintEqualToAnchor(view.layoutMarginsGuide.leadingAnchor, constant: 0.0),
            greenView.trailingAnchor.constraintEqualToAnchor(view.layoutMarginsGuide.trailingAnchor, constant: 0.0),
            greenView.heightAnchor.constraintEqualToConstant(75)])


    }
}