Object of array in new ViewController keeps empty - ios

Question

I've a problem with an array.
There's an array with some objects of the class Car in my CarViewController:
...Car.h
#interface Car : NSObject
#property (nonatomic, strong) NSString *name;
..and Car.m
- (void)encodeWithCoder:(NSCoder *)coder;
{
[coder encodeObject:name forKey:#"name"];
}
- (id)initWithCoder:(NSCoder *)coder;
{
self = [[Car alloc] init];
if (self != nil)
{
name = [coder decodeObjectForKey:#"name"];
}
return self;
}
and CarViewController
Car *car1 = [Car new];
car1.name = #"A1";
...
cars = [NSArray arrayWithObjects: car1, car2, ..., nil];
But when I now try to have access to this array in NewViewController there is a problem:
- (IBAction)btn:(id)sender {
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"Storyboard" bundle:nil];
CarViewController *vc = (CarViewController *)[storyboard instantiateViewControllerWithIdentifier:#"CarVC"];
Car *car = [vc.cars objectAtIndex:0];
NSLog(#"%#", car.name);
}
But in the log is just written that car.name = (null).
Thanks in advance to your effort.
UPDATE:
- (IBAction)btn:(id)sender {
UINavigationController *nav = self.tabBarController.viewControllers[1];
CarViewController *vc = nav.topViewController;
Car *car = [vc.cars objectAtIndex:0];
NSLog(#"%#", car.name);
}
I've tried something (thanks to rdelmar for his effort), but the result is still the same.

Answer 1

if you put this code
Car *car1 = [Car new];
car1.name = #"A1";
...
cars = [NSArray arrayWithObjects: car1, car2, ..., nil];
in the viewDidLoad method of your view controller, the the result is normal because your view is not loaded yet. (the viewDidLoad method has not been called yet)
I'm not familiar with storyboards but I think when you call
CarViewController *vc = (CarViewController *)[storyboard instantiateViewControllerWithIdentifier:#"CarVC"];
it will instantiate a new ViewController. So if you try to access cars property it will be nil if this new viewController is not presented on screen
Apple Documentation
You use this method to create view controller objects that
you want to manipulate and present programmatically in your
application. Before you can use this method to retrieve a view
controller, you must explicitly tag it with an appropriate identifier
string in Interface Builder.
This method creates a new instance of the specified view controller
each time you call it.