2

I tried to implement a UITabBar and now I am not able to retreive a callback from a method when an item was selected. Is there a possibillity to just create a @IBAction func therefore? Or do I need to do something else?

nhgrif
  • 61,578
  • 25
  • 134
  • 173
Luca Archidiacono
  • 127
  • 2
  • 16
  • possible duplicate of [Get callback/execute some code when a tab on Tab Bar is clicked](http://stackoverflow.com/questions/3667818/get-callback-execute-some-code-when-a-tab-on-tab-bar-is-clicked) – nhgrif Aug 17 '15 at 12:06

3 Answers3

2

In order to implement UITabBar button, your view controller should conform to UITabBarDelegate protocol. You need to implement:

Swift:

func tabBar(_ tabBar: UITabBar, didSelectItem item: UITabBarItem!)

Objective-c:

- (void)tabBar:(UITabBar *)tabBar didSelectItem:(UITabBarItem *)item

You also need to set the delegate (tabBar.delegate = self) in the viewDidLoad of your ViewController

Edit: Swift 3 answer:

func tabBar(_ tabBar: UITabBar, didSelect item: UITabBarItem) {

}
Floris M
  • 1,764
  • 19
  • 18
0

Your view controller should conform to UITabBarDelegate and implement:

- (void)tabBar:(UITabBar *)tabBar didSelectItem:(UITabBarItem *)item;

This method is called when the user selects a tab (i.e. UITabBarItem).

Adam Waite
  • 19,175
  • 22
  • 126
  • 148
  • Do I have to call this method explicit in the code or when I implement it into the UITabBarDelegate is it going to be called automatically? – Luca Archidiacono Aug 17 '15 at 11:41
  • UITabBar will send this message to it's delegate when a user selects a tab. – Adam Waite Aug 17 '15 at 12:07
  • `class MyClass: UITabBarItem, UITabBarDelegate {` `class MyClass: UITabBar, UITabBarControllerDelegate, UITabBarDelegate {` Which of these implementations are correct? Also is this coding correct: `func tabBar(tabBar: UITabBar, didSelectItem item: UITabBarItem) {` FYI I disconnected the default class and connected with the new customclass and it still not working (in `main.storyboard`). – Luca Archidiacono Aug 17 '15 at 12:18
  • Why are you subclassing UITabBarItem? – Adam Waite Aug 17 '15 at 12:19
  • A tab bar item shouldn't be the delegate to the tab bar it's on. You're probably writing yourself into a retain cycle. – nhgrif Aug 17 '15 at 12:20
  • @AdamWaite I just started programming swift 1 or 2 weeks ago so I didn't knew that I was subclassing. How can I fix this? – Luca Archidiacono Aug 17 '15 at 12:28
  • @nhgrif what do you mean with that? how should I do it else? Leave it on the default class? - I didn't understand it clearly – Luca Archidiacono Aug 17 '15 at 12:28
  • I think you need to get a book and learn the basics before anything else. – Adam Waite Aug 17 '15 at 13:24
0

I finally solved the problem. I had some trouble with the Delegator-class and normal class. This fixed my problem : tabBar.delegate = self in the Main-Controllerclass

Luca Archidiacono
  • 127
  • 2
  • 16