Gesture recognition issue in navigation bar

Question

In my iPad app, I have several screen views.

What I want to do is apply a double gesture pointer to the navigation bar. But I was not successful, however, when the same gesture recognizer applied to this opinion, it works.

Here is the code I'm using:

// Create gesture recognizer, notice the selector method UITapGestureRecognizer *oneFingerTwoTaps = [[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(oneFingerTwoTaps)] autorelease]; // Set required taps and number of touches [oneFingerTwoTaps setNumberOfTapsRequired:2]; [oneFingerTwoTaps setNumberOfTouchesRequired:1]; [self.view addGestureRecognizer:oneFingerTwoTaps]; 

This works in view mode, but when it is done:

 [self.navigationController.navigationBar addGestureRecognizer:oneFingerTwoTaps] 

does not work.

Answer 1

To do this, you need to subclass UINavigationBar, redefine the init button in it and add your gesture recognizer there.

So, say that you are creating a subclass of "CustomNavigationBar" - in your m file you will have an init method like this:

 - (id)initWithCoder:(NSCoder *)aDecoder { if ((self = [super initWithCoder:aDecoder])) { UISwipeGestureRecognizer *swipeRight; swipeRight = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(didSwipeRight:)]; [swipeRight setDirection:UISwipeGestureRecognizerDirectionRight]; [swipeRight setNumberOfTouchesRequired:1]; [swipeRight setEnabled:YES]; [self addGestureRecognizer:swipeRight]; } return self; } 

Then you need to set the class name of your navigation bar in the interface builder for the name of your subclass.

It’s also convenient to add a delegate protocol to the navigation bar to listen for methods sent at the end of your gestures. For example - in the case of the above, swipe right:

 @protocol CustomNavigationbarDelegate <NSObject> - (void)customNavBarDidFinishSwipeRight; @end 

then in the m file - in the recognized gesture method (no matter what you do) you can call this delegate method.

Hope this helps

Answer 2

For everyone who views this, this is a much simpler way to do this.

 [self.navigationController.view addGestureRecognizer:oneFingerTwoTaps];