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

San Francisco
San Francisco
28,373 Points

Challenge Task 2 of 3 in Stage 3 Creating a Data Model (Obj-C)

I'm a moron but please help...tried everything to no avail...please post a working code example not theory or hints.

#import "UIViewController.h"

@interface ViewController : UIViewController

@property (strong, nonatomic) NSString *shoppingCart;

@property (strong, nonatomic) NSArray *shoppingList;

#import "ViewController.h"

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    // Add your code below!

    NSArray *shoppingList = [[NSArray alloc]initWithObjects:@"toothpaste", @"bread", @"eggs", nil];
    self.shoppingList.text = [shoppingList objectAtIndex:0,1,2];


2 Answers

Chris Shaw
Chris Shaw
26,662 Points

Hi San Francisco,

You're almost there, you just have some simple errors.

  1. You've assigned shoppingList as a local variable within the viewDidLoad method, the NSArray instance should be assigned to the class property instead

  2. You're trying to assign an object to self.shoppingList.text which won't work as shoppingList is of the type NSArray

  3. The objectAtIndex method only accepts a single argument which is an integer, for this you only need the number 2

self.shoppingList = [[NSArray alloc] initWithObjects:@"toothpaste", @"bread", @"eggs", nil]
self.shoppingCart = [self.shoppingList objectAtIndex:2];

Happy coding!