Clint Clint - 7 months ago 22
Swift Question

UIButton Constraint Failure, but works with UILabel

I am trying to add a button pragmatically to a UIView. This code will work with a UI label, but when using it with a button, the constraints fail. How can I make this work? Thanks.

let homeButton = UIButton(frame: CGRectZero)
homeButton.setTitle("Home", forState: .Normal)
homeButton.titleLabel!.textAlignment = NSTextAlignment.Center
homeButton.titleLabel!.textColor = UIColor.whiteColor()
homeButton.titleLabel!.translatesAutoresizingMaskIntoConstraints = false
containerView.addSubview(homeButton)

let buttonWidthConstraint = NSLayoutConstraint(item: homeButton, attribute: .Width, relatedBy: .Equal, toItem: self.containerView, attribute: .Width, multiplier: 0.5, constant: 0)
containerView.addConstraint(buttonWidthConstraint)
let buttonHeightConstraint = NSLayoutConstraint(item: homeButton, attribute: .Height, relatedBy: .Equal, toItem: self.containerView, attribute: .Height, multiplier: 0.5,constant: 0)
containerView.addConstraint(buttonHeightConstraint)

let buttonXConstraint = NSLayoutConstraint(item: homeButton, attribute: .CenterX, relatedBy: .Equal, toItem: self.containerView, attribute: .CenterX, multiplier: 1, constant: 0)
let buttonYConstraint = NSLayoutConstraint(item: homeButton, attribute: .CenterY, relatedBy: .Equal, toItem: self.containerView, attribute: .CenterY, multiplier: 1, constant: 0)
containerView.addConstraint(buttonXConstraint)
containerView.addConstraint(buttonYConstraint)

Answer

you should use homeButton.translatesAutoresizingMaskIntoConstraints = false instead of homeButton.titleLabel!.translatesAutoresizingMaskIntoConstraints = false.

because you should disable autoresizingmask for button not for button's titleLabel!!!

Hope this will help :)