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

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

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!