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Martel Storm
4,157 PointsConstraints in Code: Code Challenge: It says I can't use an array. I say bologna! Where did I mess up?
I might be retarded
class MyViewController: UIViewController {
let sampleView = UIView()
override func viewDidLoad() {
super.viewDidLoad()
view.addSubview(sampleView)
}
override func viewWillLayoutSubviews() {
super.viewWillLayoutSubviews()
sampleView.translatesAutoresizingMaskIntoConstraints = false
// Add constraints below
func sampleViewConstraints() {
sampleView.translatesAutoresizingMaskIntoConstraints = false
let sampleViewCenterX = NSLayoutConstraint(item: sampleView, attribute: .centerX, relatedBy: .equal, toItem: view, attribute: .centerX, multiplier: 1.0, constant: 0.0)
let sampleViewCenterY = NSLayoutConstraint(item: sampleView, attribute: .centerY, relatedBy: .equal, toItem: view, attribute: .centerY, multiplier: 1.0, constant: 0.0)
let sampleViewHeight = NSLayoutConstraint(item: sampleView, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1.0, constant: 50.0)
let sampleViewWidth = NSLayoutConstraint(item: sampleView, attribute: .width, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1.0, constant: 50.0)
view.addConstraint([
sampleViewWidth,
sampleViewHeight,
sampleViewCenterX,
sampleViewCenterY])
}
}
}
1 Answer

Aniruddha Shukla
2,846 PointsThe method name is addConstraints and not addConstraint. It takes in an array of Constraints. Also, another thing that I see off is whats another method doing in the viewWillLayoutSubviews?
Try this with the fixed changes
class MyViewController: UIViewController {
let sampleView = UIView()
override func viewDidLoad() {
super.viewDidLoad()
view.addSubview(sampleView)
}
override func viewWillLayoutSubviews() {
super.viewWillLayoutSubviews()
sampleView.translatesAutoresizingMaskIntoConstraints = false
// Add constraints below
sampleView.translatesAutoresizingMaskIntoConstraints = false
let sampleViewCenterX = NSLayoutConstraint(item: sampleView, attribute: .centerX, relatedBy: .equal, toItem: view, attribute: .centerX, multiplier: 1.0, constant: 0.0)
let sampleViewCenterY = NSLayoutConstraint(item: sampleView, attribute: .centerY, relatedBy: .equal, toItem: view, attribute: .centerY, multiplier: 1.0, constant: 0.0)
let sampleViewHeight = NSLayoutConstraint(item: sampleView, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1.0, constant: 50.0)
let sampleViewWidth = NSLayoutConstraint(item: sampleView, attribute: .width, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1.0, constant: 50.0)
view.addConstraints([
sampleViewWidth,
sampleViewHeight,
sampleViewCenterX,
sampleViewCenterY])
}
}