How to update the constant height constraint of a UIView programmatically?

Question

I have a UIView and I set the constraints using Xcode Interface Builder.

Now I need to update that UIView instance\'s height constant progra

Answer 1

Change HeightConstraint and WidthConstraint Without creating IBOutlet.

Note: Assign height or width constraint in Storyboard or XIB file. after fetching this Constraint using this extension.

You can use this extension to fetch a height and width Constraint:

extension UIView {

var heightConstraint: NSLayoutConstraint? {
    get {
        return constraints.first(where: {
            $0.firstAttribute == .height && $0.relation == .equal
        })
    }
    set { setNeedsLayout() }
}

var widthConstraint: NSLayoutConstraint? {
    get {
        return constraints.first(where: {
            $0.firstAttribute == .width && $0.relation == .equal
        })
    }
    set { setNeedsLayout() }
}

}

You can use:

yourView.heightConstraint?.constant = newValue