Question

I have my main program with MainAppDelegate.h,MainAppDelegate.m.
I have created two custom navigation controllers ANavController, BNavController classes and have created added the controllers in Interface Builder and assigned my custom classes to the two controllers inside the MainWindow.xib

When the application first loads I make it render the first NavControllers and its view in the didFinishLaunchingWithOptions method:

[window addSubView:ANavController.view];

This is works fine and loads the first navigation controllers view. My problem is that within the view on each nav controller, inside the viewDidLoad method I have created a UIBarButtonItem which I add to the right side of the navcontroller.

I’m trying to make this button call an action method defined inside my MainAppDelegate.m.

For both of my two custom NavController classes I have set the delegate to MainAppDelegate inside interface builder. I try to define buttons like so:

[flipButton addTarget:self.delegate action:@selector(changeModeAction:) 
forControlEvents:UIControlEventTouchUpInside];

and obviously then inside MainAppDelegate.m I have defined a method:

-(void)changeModeAction:(id)sender

This method should flip the ANavigationController currently in the window to he BNavigationController.

But it obviously crashes on the addTarget:self.delegate. What’s the proper way to do this?
Basically I’m trying to add a button to the top right of each NavControl which will fire a FLIP page animation, switching to the other NavController and it’s stack.

So if you’re two levels deep on ANavController and you hit the top right button, it will flip to BNavController and wherever you were last in it’s stack. Hitting the button again will flip the page again back to ANavController and you’ll still be two levels deep, before you switched to B. Does this make sense?

I think my idea implementation needs some work?

Answer 1

Sorry for posting this as an answer instead of a comment – my reputation is too low to add comments – but could you please provide the error message?

EDIT: See thread below for details – the problem was that ‘self’ was not a subclass of UINavigationController and therefore did not have a delegate property. Changing this to self.navigationController.delegate worked.