Unrecognized selector sent to instance when I'm passing it to parent view

Question

I need to make some changes in navigationItemBar and add buttons with different objects.

Here is my code of viewDidLoad function where im adding selectors

    override func viewDidLoad() {
    super.viewDidLoad()
    
    tapGestureRecgonizer.addTarget(self, action: #selector(showAlertSheet))
    imageView.addGestureRecognizer(tapGestureRecgonizer)
    
    setupAlert()
    
    self.tabBarController?.setLeftNavBarView(selector: #selector(self.returnToGalleryScreenTab))
    self.tabBarController?.setRightNavBarView(selector: #selector(self.routeToAddPhotoForm))
}

And here is my @objc functions

    @objc func routeToAddPhotoForm() {
    self.presenter?.routeToAddPhotoForm()
}

@objc func returnToGalleryScreenTab() {
    self.tabBarController?.selectedIndex = 0
}

And my extensions for setting views in nav bar item

    func setLeftNavBarView(selector: Selector) {
    let button = UIButton(type: .custom)
    button.setTitle("Cancel", for: .normal)
    button.setTitleColor(UIColor(rgb: 0xFF5F5F5F), for: .normal)
    button.titleLabel?.font = UIFont(name: "Roboto", size: 15)
    button.addTarget(self, action: selector, for: .touchUpInside)
    button.titleEdgeInsets = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
    let barButton = UIBarButtonItem(customView: button)
    navigationItem.leftBarButtonItem = barButton
}

func setRightNavBarView(selector: Selector) {
    let button = UIButton(type: .custom)
    button.setTitle("Next", for: .normal)
    button.setTitleColor(UIColor(rgb: 0xFFCF497E), for: .normal)
    button.titleLabel?.font = UIFont(name: "Roboto-Bold", size: 15)
    button.addTarget(self, action: selector, for: .touchUpInside)
    button.titleEdgeInsets = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
    let barButton = UIBarButtonItem(customView: button)
    navigationItem.rightBarButtonItem = barButton
}

But when I'm trying to tap on buttons in NavigationBarItem I'm getting error like "'-[UITabBarController returnToGalleryScreenTab]: unrecognized selector sent to instance 0x13f00fa00'". What am I doing wrong. I think my problem is that I'm passing my @objc functions to parent view function but I don't know how can I do it in another way

Answer 1

Following two functions -

@objc func routeToAddPhotoForm() {
}

@objc func returnToGalleryScreenTab() {
}

should be in your UITabBarController subclass.

The reason is - self points to your UITabBarController subclass here - NOT the other class you are calling it from.

button.addTarget(self, action: selector, for: .touchUpInside)

---

The other way would be following -

func setLeftNavBarView(target: Any, selector: Selector) {
    // Use `target` instead of `self` here
    button.addTarget(target, action: selector, for: .touchUpInside)
}

func setRightNavBarView(target: Any, selector: Selector) {
    // Use `target` instead of `self` here
    button.addTarget(target, action: selector, for: .touchUpInside)
}

From call site -

self.tabBarController?.setLeftNavBarView(target: self, selector: #selector(self.returnToGalleryScreenTab))
self.tabBarController?.setRightNavBarView(target: self, selector: #selector(self.routeToAddPhotoForm))