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Start your free trialSheng Wei
4,382 Points[Help!] How to create view constraint?
Please help! Im not sure what is wrong with my code, thank you
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([
NSLayoutConstraint(item: greenView, attribute: .Height, relatedBy: .Equal, toItem: nil, attribute: .NotAnAttribute, multiplier: 1.0, constant: 75.0),
NSLayoutConstraint(item: greenView, attribute: .Left, relatedBy: .Equal, toItem: view, attribute: .LeftMargin, multiplier: 1.0, constant: 8.0),
NSLayoutConstraint(item: greenView, attribute: .Right, relatedBy: .Equal, toItem: view, attribute: .RightMargin, multiplier: 1.0, constant: 8.0),
greenView.bottomAnchor.constraintEqualToAnchor(blueView.bottomAnchor, constant: 8.0)
])
}
}
1 Answer
Greg Kaleka
39,021 PointsHi Sheng,
Check out the error message you get with your code: the right margin should be -8 points. Right now you have +8 points. Simply add a - in the right margin's value and you'll be all set.
Cheers
-Greg
Sheng Wei
4,382 PointsSheng Wei
4,382 PointsAwesome! Thanks so much Greg. Would you mind answering my question on the same module about constraints as well? I posted it a few days back