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iOS Build a Simple iPhone App with Objective-C Creating a Data Model Creating a Data Collection

Posted by Fidan Faizullin
Fidan Faizullin
3,007 Points

I'm stuck

What is wrong here?

ViewController.h 
#import "UIViewController.h"

@interface ViewController : UIViewController

@property (strong, nonatomic) NSString *shoppingCart;

@property (strong, nonatomic) NSArray *shoppingList;

@end
ViewController.m 
#import "ViewController.h"

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    // Add your code below!
    NSArray *shoppingList = [[NSArray alloc] initWithObjects:@"toothpaste", @"bread", @"eggs", nil];

}

@end

1 Answer

Martin Wildfeuer
PLUS
Martin Wildfeuer
Courses Plus Student 11,071 Points
Martin Wildfeuer
Martin Wildfeuer
Courses Plus Student 11,071 Points

Your interface is correct.

In your implementation file, however, you are doing the following in viewDidLoad:

NSArray *shoppingList = [[NSArray alloc] initWithObjects:@"toothpaste", @"bread", @"eggs", nil];

This way, you are not assigning it to the property shoppingList you just declared in your interface, but you are creating a brand new NSArray, also called shoppingList. You can access the properties of your class via self, thus you should do the following:

self.shoppingList = [[NSArray alloc] initWithObjects:@"toothpaste", @"bread", @"eggs", nil];

Btw., there is an even shorter way to write this

self.shoppingList = @[ @"toothpaste", @"bread", @"eggs" ];

This is called literal syntax, where an array is instantiated with square brackets like this @[]

Hope that helps!