Data passed to prepareForSegue is nil

Question

I'm trying to get IngredientViewController to update an array belongs to the controller that called it via the segue (FridgeViewController)

In IngredientViewController fridgeManager is nil no matter what I try

The code:

FridgeViewController:

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    // Get the new view controller using [segue destinationViewController].
    // Pass the selected object to the new view controller.
    IngredientViewController *controller = (IngredientViewController *)segue.destinationViewController;
    [controller setFridgeManager:fridgeManager];
}

IngredientViewController:

@property (strong, nonatomic) FridgeDataManager *fridgeManager;

and in viewDidLoad fridgeManager is nil (and in any other method of coarse)

Answer 1

synthesize this fridgeManager property in IngredientViewController.m

@synthesize fridgeManager; 

Answer 2

In newer versions of Xcode, you don't need to synthesize your properties, OR create an instance variable. If you don't do either, then Xcode creates an instance variable with a "_" prefix to match your property. (I believe this was is a change that was part of Objective C 2.0.)

So

@property (nonatomic, strong) NSString *foo;

Gives you an instance variable of `_foo.

And you could use it like:

[controller setFridgeManager: _foo];

If you have both a property fridgeManager and an instance variable fridgeManager, they are likely different entities, so setting

fridgeManager = x;

Would change a different instance variable than setting

self.fridgeManager = x;