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

Justin Whedon
Justin Whedon
19,811 Points
Posted by Justin Whedon
Justin Whedon
19,811 Points

Having issues with task 3 of 3 on the shoppingCart challenge.

What am I doing wrong here? Trying to add 'eggs' to the 'shoppingCart'.

import "ViewController.h"

@implementation ViewController

  • (void)viewDidLoad { [super viewDidLoad]; self.shoppingList = [[NSArray alloc] initWithObjects:@"toothpaste",@"bread", @"eggs",nil]; NSString *shoppingCart = [shoppingList objectAtIndex:2]; }

@end

ViewController.h 
#import "UIViewController.h"

@interface ViewController : UIViewController

@property (strong, nonatomic) NSString *shoppingCart;
@property (nonatomic, strong) NSArray *shoppingList;

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

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    self.shoppingList = [[NSArray alloc] initWithObjects:@"toothpaste",@"bread", @"eggs",nil];
    NSString *shoppingCart = [shoppingList objectAtIndex:2];
}

@end

1 Answer

Rashii Henry
Rashii Henry
16,433 Points
Rashii Henry
Rashii Henry
16,433 Points

Hey Justin,

once you declare a property in a viewController. It becomes accessible all throughout that class. You did that in your header file flawlessly, with shoppingCart.

However, in your implementation, you created a new instance of shoppingCart, sorta like you didn't want to use what you had already created.

Now the compiler is assigning it to a different location. So try using the syntax you have with your shoppingList. You should be good to go.