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

create an extension for barbutton item.

 extension UINavigationItem {
    func addSettingButtonOnRight(){
       let button = UIButton(type: .Custom)
       button.setTitle("setting", forState: .Normal)
       button.titleLabel?.font = UIFont.systemFontOfSize(15.0)
       button.layer.cornerRadius = 5
       button.backgroundColor = UIColor.grayColor()
       button.frame = CGRect(x: 0, y: 0, width: 100, height: 25)
       button.addTarget(self, action: #selector(gotSettingPage), forControlEvents: UIControlEvents.TouchUpInside)
       let barButton = UIBarButtonItem(customView: button)

       self.rightBarButtonItem = barButton
   }

   func gotSettingPage(){

   }
 }

And call it from viewDidLoad()

 self.navigationItem.addSettingButtonOnRight()