iphone connecting code to the 'back' button

Question

Is there a way to connect code to a view's 'back' button that is part of a navigation controller? That back button is automatically coded in by the nature of it being a navigation controller so I am not sure how I can connect code to it.

(I know this should be really easy but I can't seem to find it in the documentation on navigation controller.)

http://stackoverflow.com/questions/1214965/setting-action-for-back-button-in-navigation-controller/3445994#3445994 — William Jockusch, Aug 17 '10 at 23:12

score 1 · Answer 1 · answered Aug 18 '10 at 00:51

1

viewWillDisappear is where you would typically add code to execute when the back button is pressed

answered Aug 18 '10 at 00:51

DVG

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I am trying to update NSUserDefaults and that doesnt seem to be working. – startuprob Aug 18 '10 at 02:38

score 0 · Answer 2 · answered Feb 22 '13 at 17:57

You could check if the controller was popped in viewWillDisapper, like in this example:

- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];
    if ([self.navigationController.viewControllers indexOfObject:self]==NSNotFound) {
        // back button was pressed.  We know this is true because self is no longer
        // in the navigation stack.
        NSLog(@"Article done");
    }
}

score 0 · Accepted Answer · answered Aug 18 '10 at 00:53

0

In reality you should not have a code that needs to be executed when Back button is pressed. What exactly you're trying to achieve?

answered Aug 18 '10 at 00:53

sha

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I am trying to store codes into NSUserDefaults when the back button is pressed. – startuprob Aug 18 '10 at 02:35
You should save something as soon as corresponding control has changed, not when you press Back button. – sha Aug 18 '10 at 02:39

iphone connecting code to the 'back' button

3 Answers3