View Controller Swapping Problem

[bate5150]

Hi, I was wondering if someone could tell me what I'm doing wrong here. I'm making a simple application that I can use as a template for future projects that use nested view controllers. The code should work, or at least I thought. Here is the part of code that's causing my app to crash when I attempt to run it:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    
	
    [window makeKeyAndVisible];
	FirstViewController *aView = [[FirstViewController alloc] initWithNibName:@"FirstViewController" bundle:nil];
	self.firstView = aView;
	
//The next line, where I add the subview, is what
//is making my app crash when I try to run it

        [window addSubview:firstView.view];
	[aView release];
	
	return YES;
}

The FirstViewController class has no instance variables, its .xib file just has a button linked to a function for switching between itself and the second controller. The two view controllers swap by calling a method from the delegate class that does a simple animation and replaces one view with the other.

The debugger just tells me that the app terminates due to an uncaught exception, but I don't know what I did wrong. If you need to see more of the code just ask. Help

[Mike J]

Try this:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    
	
    [window makeKeyAndVisible];
	FirstViewController *aView = [[FirstViewController alloc] initWithNibName:@"FirstViewController" bundle:nil];
		[self setfirstView:aView];
        [window addSubview:firstView.view];
	[aView release];
	
	return YES;
}

Originally Posted by bate5150

Hi, I was wondering if someone could tell me what I'm doing wrong here. I'm making a simple application that I can use as a template for future projects that use nested view controllers. The code should work, or at least I thought. Here is the part of code that's causing my app to crash when I attempt to run it:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    
	
    [window makeKeyAndVisible];
	FirstViewController *aView = [[FirstViewController alloc] initWithNibName:@"FirstViewController" bundle:nil];
	self.firstView = aView;
	
//The next line, where I add the subview, is what
//is making my app crash when I try to run it

        [window addSubview:firstView.view];
	[aView release];
	
	return YES;
}

The FirstViewController class has no instance variables, its .xib file just has a button linked to a function for switching between itself and the second controller. The two view controllers swap by calling a method from the delegate class that does a simple animation and replaces one view with the other.

The debugger just tells me that the app terminates due to an uncaught exception, but I don't know what I did wrong. If you need to see more of the code just ask. Help

[bate5150]

Originally Posted by Mike J

Try this:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    
	
    [window makeKeyAndVisible];
	FirstViewController *aView = [[FirstViewController alloc] initWithNibName:@"FirstViewController" bundle:nil];
		[self setfirstView:aView];
        [window addSubview:firstView.view];
	[aView release];
	
	return YES;
}

Thanks for the response.

I tried that but no dice, I'm at a loss because it really seems to me like it should work. I've followed the program step by step through almost everything and it just terminates here...

[Innovation]

In your NIB check to make sure it has it's view property set. If it doesn't have a view add one to the NIB, then right click on the file owner (should be FirstViewController) and set the view outlet to the added view. This is a usual suspect.

Originally Posted by bate5150

Thanks for the response.

I tried that but no dice, I'm at a loss because it really seems to me like it should work. I've followed the program step by step through almost everything and it just terminates here...

[imsatasia]

Originally Posted by bate5150

Thanks for the response.

I tried that but no dice, I'm at a loss because it really seems to me like it should work. I've followed the program step by step through almost everything and it just terminates here...

Try the following:

FirstViewController *aView = [[FirstViewController alloc] initWithNibName:@"FirstViewController" bundle:nil];
	
[window addSubview:aView];
[aView release];

[bate5150]

Originally Posted by Innovation

In your NIB check to make sure it has its view property set. If it doesn't have a view add one to the NIB, then right click on the file owner (should be FirstViewController) and set the view outlet to the added view. This is a usual suspect.

I checked to make sure but the nib has a view and its outlet is set to the view. Also File's Owner is of the FirstViewController class so that's not the problem either.

[bate5150]

Originally Posted by imsatasia

Try the following:

FirstViewController *aView = [[FirstViewController alloc] initWithNibName:@"FirstViewController" bundle:nil];
	
[window addSubview:aView];
[aView release];

This probably won't work, aView cannot be used as an argument for addSubview, it needs UIView and aView is from class FirstViewController.

I tried using aView.view but it also crashed when I tried this.