Programattically set barbutton " System Item" - ios

Question

I want to set share button on rightbarbuttonitem of navigation controller.
I don't want to add custom images , I want use share button image provided by Xcode.This is how I do in storyboard.
I set Style , and set System_Item as Action.
Now the question is how do I set System_Item programatically, if I create barbuttonitem programatically ?
let shareButton = UIBarButtonItem(title: "",
style: .plain,
target: self,
action: #selector(shareAction(sender:)))
shareButton.tintColor = AppColor.barButtonColor
navigationItem.rightBarButtonItem = shareButton

Answer 1

you need to use UIBarButtonSystemItemAction option to get share action directly
let share = UIBarButtonItem(barButtonSystemItem: .action, target: self, action: #selector(shareAction(sender:)))
shareButton.tintColor = AppColor.barButtonColor
navigationItem.rightBarButtonItem = share
and handle the action as like
#objc func shareAction(sender: UIBarButtonItem) {
}

Answer 2

You can create an extension to do this ->
public extension UIViewController {
func setRightBarButtonItem(tintColor: UIColor = AppColor.barButtonColor) {
let button = UIButton(type: .system)
button.tintColor = tintColor
button.setImage(UIImage(.action), for: .normal) // <-- Set system icon to button
button.translatesAutoresizingMaskIntoConstraints = false
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(tap))
button.addGestureRecognizer(tapGesture)
navigationItem.rightBarButtonItem = UIBarButtonItem(customView: button)
}
#objc func tap() {
// Do stuff
}
}
Then in your ViewController
override func viewDidLoad() {
super.viewDidLoad()
setRightBarButtonItem()
// OR
setRightBarButtonItem(tintColor: .blue)
}
UIImage extension to use system icons without version control
extension UIImage {
public convenience init?(_ systemItem: UIBarButtonItem.SystemItem) {
guard let sysImage = UIImage.imageFrom(systemItem: systemItem)?.cgImage else {
return nil
}
self.init(cgImage: sysImage)
}
private class func imageFrom(systemItem: UIBarButtonItem.SystemItem) -> UIImage? {
let sysBarButtonItem = UIBarButtonItem(barButtonSystemItem: systemItem, target: nil, action: nil)
let toolBar = UIToolbar()
toolBar.setItems([sysBarButtonItem], animated: false)
toolBar.snapshotView(afterScreenUpdates: true)
if let buttonView = sysBarButtonItem.value(forKey: "view") as? UIView{
for subView in buttonView.subviews where subView is UIButton {
let button = subView as! UIButton
let image = button.imageView!.image!
return image
}
}
return nil
}
}