How to change the position of navigationItem titleView

Question

I'm trying to create custom titleView and change the position to be next to the back button.

The titleView should be look like :

So what i did was :

private func setupNavigationItems() {

    let label = UILabel()

    label.translatesAutoresizingMaskIntoConstraints = false

    label.text = "Info"
    label.textColor = UIColor.black
    label.textAlignment = .left
    navigationItem.titleView = label

    if let navigationBar = navigationController?.navigationBar {
        label.widthAnchor.constraint(equalTo: navigationBar.widthAnchor, constant: -40).isActive = true
    }

    self.navigationController?.navigationBar.tintColor = UIColor.black
}


override func updateViewConstraints() {
    super.updateViewConstraints()
    setupNavigationItems()
}

It works, but in some situation i get crash :

*** Terminating app due to uncaught exception 'NSGenericException', reason: 'Unable to activate constraint with anchors and because they have no common ancestor. Does the constraint or its anchors reference items in different view hierarchies? That's illegal.'

How can i fix this crash?, there is a better way to change the position of the navigation title?

Thanks

score 1 · Answer 1 · answered Mar 20 '19 at 10:48

To get that effect you want to use:

navigationItem.backBarButtonItem

and not:

navigationItem.titleView

the backBarButtonItem will automatically show the title of your previous viewcontroller but can be modified to anything you like as shown here:

How to set back button text in Swift

Datt Patel · Answer 2 · 2018-01-19T07:46:27.623

replace this code :-

label.widthAnchor.constraint(equalTo: navigationBar.widthAnchor, constant: -40).isActive = true

with this code :-

label.widthAnchor.constraint(equalTo: navigationBar.widthAnchor, multiplier: 0.8).isActive = true

Change multiplier according your need.

OR

set frame of UILabel without constraint.

let lbl = UILabel(frame: CGRect(x: 0, y: 0, width: self.view.frame.size.width * 0.8, height: 44))
lbl.text = "Info"
lbl.textColor = .black
lbl.textAlignment = .left
navigationItem.titleView = lbl

How to change the position of navigationItem titleView

2 Answers2