Confirm back button on UINavigationController

Question

I am using the storyboard for my app which is using UINavigationController. I would like to add a confirmation dialog to the default back button so

Answer 1

Actually, you can find the Back button view and add UITapGestureRecognizer to it.

If you look at this image: Using this code:

@interface UIView (debug)
- (NSString *)recursiveDescription;
@end

@implementation newViewController
... 
NSLog(@"%@", [self.navigationController.navigationBar recursiveDescription]);

You can realize how to find the View of the Back button. It is always the last one in subviews array of the navigationbar.

2012-05-11 14:56:32.572 backBtn[65281:f803] >
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So I used:

UIView *backButton = [[navBar subviews] lastObject];
[backButton setUserInteractionEnabled:YES];

UITapGestureRecognizer *tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(alertMsg)];
[tapGestureRecognizer setNumberOfTapsRequired:1];
[backButton addGestureRecognizer:tapGestureRecognizer];

Tapping on back button and voilà: