storyboard instantiateViewControllerWithIdentifier not setting IBOutlets

Question

I am using storyboard instantiateViewControllerWithIdentifier: and I\'m noticing that all the IBOutlets I have wired up are still nil. However, the

Answer 1

If the object you're linking to is a top-level entity in the scene, like an ArrayController, the reference needs to be strong (not weak!) since it's not retained by the view hierarchy. A weak reference can cause a problem like what you describe.

Look here for more information: Should IBOutlets be strong or weak under ARC?

Answer 2

People gave solution of how to get the view loaded (some of which you should never use (loadView()) so here is a way to check whether your view is already loaded

I ran into the problem because I had a property with a didSet observer to update the UI which obviously doesn't work if the outlets are not yet set, so here is some example code how to work around it:

var name: String? {
    didSet {
        updateNameLabel()
    }
}

override func viewDidLoad() {
    super.viewDidLoad()

    updateNameLabel()
}

func updateRoomLabel() {
    guard isViewLoaded() else {
        return
    }
    [...]
}

So now when you display the outlets get updated but also every time you update the property

Answer 3

[Use me as bad example]

Maybe not a good idea after all, it works but it violates the regular loading making the app unstable ^_^.
I'll leave the answer here in case someone else want to know if you do it.

---

I was having the same issue, however the custom component I designed isn't loaded via presentViewController (load in overlay to the previous view)

You can simply call

myViewController.loadView() //Swift

[myViewController loadView] //Obj-C

Answer 4

Setting the frame for the instantiated ViewController seems to set the IBOutlets.

ex:

DemoViewController *demoVC = [[self storyboard] instantiateViewControllerWithIdentifier:@"demoVC"];
demoVC.frame = self.view.frame; //or CGRectMake(0, 0, 1015, 604);

This would initialize the IBOutlets of DemoViewController like Label, TextField, Button, Table etc,.

Hope this helps.

Answer 5

The view seems to be initialized properly only after it is accessed first. The problem goes away when calling

[self presentViewController:vc animated:NO completion:nil];

or more simply

[vc view];

Answer 6

Outlets are established with Key Value Coding, you could put this into your view controller subclass:

- (void)setValue:(id)value forKeyPath:(NSString *)keyPath {
    [super setValue:value forKeyPath:keyPath];
}

- (void)setValue:(id)value forKey:(NSString *)key {
    [super setValue:value forKeyPath:key];
}

And put a breakpoint on the two calls to super.

In the debugger, I'd try:

1. Comparing 'self' to the view controller you think you're applying the outlets to. Perhaps your storyboard has a second view controller you're not expecting. When you said you 'set up an owner' I thought that was strange terminology. Did you drag out one of the cube objects to represent your view controller in addition to the representation that's already there?

2. Compare [self valueForKey:key] or [self valueForKeyPath:keyPath] or just [self outletName] with the passed in value after the call through to super. Maybe you have setter that isn't doing what you intend. I've seen one mistake like this come up a couple of times where people have an outlet for an object with a name like "firstName" and then an action with the selector "setFirstName:". That confuses key value coding, and you end up with setFirstName: getting called during nib loading with intent of establishing the outlet, but the setter for the outlet is implemented as an action method, so the outlet is never set.