How to programmatically set action for barButtonItem in swift 3?

Question

Here is what I used previously,

var barButtonItem = UIBarButtonItem(image: backImgs, style: UIBarButtonItemStyle.plain, target: self, action: Selector(\"menu         


        

Answer 1

Make a UIBarButtonItem:

let rightButton: UIBarButtonItem = UIBarButtonItem(title: "Done", style: UIBarButtonItemStyle.done, target: self, action: #selector(LocationViewController.doneButtonClicked(_:)))

Add to NavigationItem:

self.navigationItem.rightBarButtonItem = rightButton

Associated function:

func doneButtonClicked(_ button:UIBarButtonItem!){    
    print("Done clicked")    
}

Answer 2

let barButtonItem = UIBarButtonItem(image: UIImage(named: "backImgs"),
                                            style: .plain,
                                            target: self,
                                            action: #selector(menuButtonTapped))

// Adding button to navigation bar (rightBarButtonItem or leftBarButtonItem)
self.navigationItem.rightBarButtonItem = barButtonItem

 // Private action
@objc fileprivate func menuButtonTapped() { // body method here }

Answer 3

Summarize the mostly used method in Swift 3 for adding action to a barButton.

1. Barbutton with text

   navigationItem.rightBarButtonItem = UIBarButtonItem(title: "Add", style: .plain, target: self, action: #selector(addTapped))
   

2. BarButton with your own image

   navigationItem.rightBarButtonItem = UIBarButtonItem(image: UIImage(named:"add"), style: .plain, target: self, action: #selector(addTapped))
   

3. BarButton with system image

   navigationItem.rightBarButtonItem = UIBarButtonItem(barButtonSystemItem: .add, target: self, action: #selector(addTapped))
   

Answer 4

If someone is looking for a way to set the action on an existing button (Swift 5):

if let leftBarButtonItem = navigationItem.leftBarButtonItem {
    leftBarButtonItem.target = self
    leftBarButtonItem.action = #selector(onBack(_:))
}


@IBAction func onBack(_ sender: AnyObject) {
    _ = navigationController?.popViewController(animated: true)
}

Answer 5

You just need to change your selector syntax as of from Swift 3 you need to specify the first parameter name of method in your function call so change your selector like this.

#selector(menuButtonTapped(sender:))

And your method should be like this.

func menuButtonTapped(sender: UIBarButtonItem) {

}

Answer 6

If anyone is using customView:

barButtonItem.customView?.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(onBarButtonItemClicked)))