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UIBarButtonItem
target-action
iOS development
Swift
troubleshooting

UIBarButtonItem target-action not working?

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Introduction

When a UIBarButtonItem tap does nothing, the issue is almost always one of these: the target is nil (deallocated or never set), the action selector is misspelled or has the wrong signature, the button was created with a custom view that absorbs touches, or isEnabled is false. Unlike UIButton, UIBarButtonItem does not inherit from UIView and has its own quirks with the target-action pattern.

Basic Correct Setup

swift
1class ViewController: UIViewController {
2    override func viewDidLoad() {
3        super.viewDidLoad()
4
5        navigationItem.rightBarButtonItem = UIBarButtonItem(
6            title: "Save",
7            style: .plain,
8            target: self,
9            action: #selector(saveTapped)
10        )
11    }
12
13    @objc func saveTapped() {
14        print("Save tapped!")
15    }
16}

Key requirements:

  • target is self (not nil)
  • Action method is marked @objc
  • Selector matches the method name exactly

Problem 1: Target is nil

swift
1// WRONG — target is nil, action goes nowhere
2navigationItem.rightBarButtonItem = UIBarButtonItem(
3    title: "Save",
4    style: .plain,
5    target: nil,           // <-- nil target
6    action: #selector(saveTapped)
7)

When target is nil, UIKit sends the action up the responder chain. If no responder implements the selector, nothing happens — no crash, no warning, just silence.

Fix: Always set target: self (or the appropriate object).

Problem 2: Missing @objc

swift
1// WRONG — method not exposed to Objective-C runtime
2func saveTapped() {
3    print("Save tapped!")
4}
5
6// CORRECT
7@objc func saveTapped() {
8    print("Save tapped!")
9}

The target-action pattern uses Objective-C message dispatch. Without @objc, the method is invisible to the runtime. In modern Swift, the compiler usually catches this with #selector, but it can slip through if you set the action as a string.

Problem 3: Wrong Selector Signature

swift
1// These are DIFFERENT selectors:
2#selector(saveTapped)          // saveTapped()
3#selector(saveTapped(_:))      // saveTapped(_ sender: UIBarButtonItem)
4
5// If your method has a parameter:
6@objc func saveTapped(_ sender: UIBarButtonItem) {
7    print("Tapped: \(sender.title ?? "")")
8}
9
10// Use the matching selector:
11UIBarButtonItem(
12    title: "Save",
13    style: .plain,
14    target: self,
15    action: #selector(saveTapped(_:))  // Note the (_:)
16)

A mismatch between the selector and method signature causes a crash (unrecognized selector) or silent failure.

Problem 4: Custom View Absorbs Touches

swift
1// WRONG — custom view button may intercept touches
2let button = UIButton(type: .system)
3button.setTitle("Save", for: .normal)
4
5let barButton = UIBarButtonItem(customView: button)
6barButton.target = self
7barButton.action = #selector(saveTapped)
8// target/action on UIBarButtonItem is IGNORED for custom views

When you create a UIBarButtonItem with customView:, the bar button item's own target and action are not used. The custom view handles its own touches.

Fix: Add the action to the custom view directly:

swift
1let button = UIButton(type: .system)
2button.setTitle("Save", for: .normal)
3button.addTarget(self, action: #selector(saveTapped), for: .touchUpInside)
4
5navigationItem.rightBarButtonItem = UIBarButtonItem(customView: button)

Problem 5: Button is Disabled

swift
1let barButton = UIBarButtonItem(
2    title: "Save",
3    style: .plain,
4    target: self,
5    action: #selector(saveTapped)
6)
7barButton.isEnabled = false  // Grayed out, won't respond to taps
8
9navigationItem.rightBarButtonItem = barButton

Check that isEnabled is true. The button appears dimmed when disabled, but it can be hard to notice.

Problem 6: View Controller is Deallocated

swift
1func setupNavigation() {
2    let vc = DetailViewController()
3    // vc is a local variable — it gets deallocated after this method returns
4    navigationItem.rightBarButtonItem = UIBarButtonItem(
5        title: "Save",
6        style: .plain,
7        target: vc,         // vc is about to be deallocated
8        action: #selector(DetailViewController.saveTapped)
9    )
10}

The target is not retained by UIBarButtonItem. If the target object is deallocated, the action goes to nil (no crash, no response).

Fix: Ensure the target stays alive for the lifetime of the button.

Problem 7: System Item with Target-Action

swift
1let doneButton = UIBarButtonItem(
2    barButtonSystemItem: .done,
3    target: self,
4    action: #selector(doneTapped)
5)
6// This works correctly — system items support target-action
7toolbarItems = [doneButton]

System items (.done, .cancel, .add, etc.) work with target-action. But make sure the toolbar or navigation bar is actually visible.

Problem 8: Not in Navigation Controller

swift
1// This button won't appear if there's no navigation controller
2navigationItem.rightBarButtonItem = UIBarButtonItem(
3    title: "Save",
4    style: .plain,
5    target: self,
6    action: #selector(saveTapped)
7)
8
9// Check: is the view controller inside a UINavigationController?
10print(navigationController)  // nil means no navigation bar is shown

navigationItem only shows buttons when the view controller is embedded in a UINavigationController.

Debugging Checklist

swift
1// 1. Is the button visible?
2print(navigationItem.rightBarButtonItem)  // Should not be nil
3
4// 2. Is target set?
5print(navigationItem.rightBarButtonItem?.target)  // Should not be nil
6
7// 3. Is it enabled?
8print(navigationItem.rightBarButtonItem?.isEnabled)  // Should be true
9
10// 4. Is there a navigation controller?
11print(navigationController)  // Should not be nil
12
13// 5. Does the action method exist?
14print(responds(to: #selector(saveTapped)))  // Should be true

Common Pitfalls

  • Custom view ignores target-action: UIBarButtonItem(customView:) does not use its own target/action. Add touch handling to the custom view itself.
  • Weak reference to target: UIBarButtonItem does not retain its target. If the target is deallocated (common with closures or temporary objects), taps silently fail.
  • Setting action after init: Assigning barButton.action = #selector(newAction) works, but make sure barButton.target is also set — it defaults to nil.
  • Toolbar vs Navigation bar: toolbarItems appear in the toolbar (at the bottom), navigationItem buttons appear in the navigation bar (at the top). Putting buttons in the wrong collection makes them invisible.
  • Responder chain confusion: With target: nil, the action travels the responder chain. This works only if a responder in the chain implements the selector. It is fragile and hard to debug — always set an explicit target.

Summary

  • Always set target: self and mark action methods with @objc
  • Ensure the selector matches the method signature exactly (saveTapped vs saveTapped(_:))
  • Custom view bar button items ignore target/action — add actions to the custom view directly
  • Check isEnabled, verify the target is not deallocated, and confirm a UINavigationController exists
  • Use responds(to:) and print debugging to verify the target-action chain
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