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

Posted by ira auerbach
ira auerbach
165 Points

What is wrong with this code?

  • (void)viewDidLoad { [super viewDidLoad];

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

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

@end

3 Answers

William Li
PLUS
William Li
Courses Plus Student 26,868 Points
William Li
William Li
Courses Plus Student 26,868 Points
  • shoppingList already declared as NSArray in the header file, so you don't need to do that again in the .m file
  • don't forget the nil at the end of initWithObjects.
self.shoppingList = [[NSArray alloc] initWithObjects:@"toothpaste", @"bread", @"eggs", nil];
ajor
ajor
8,216 Points
ajor
ajor
8,216 Points

Thank you William!

I was stuck at this challenge as well. I wonder why the following syntax doesn't go through:

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

Isn't that proper short hand?

William Li
William Li
Courses Plus Student 26,868 Points
William Li
William Li
Courses Plus Student 26,868 Points

Hi, Andreas Jordan , yeah, you can absolutely use the shorthand to create the array, but your code missed an at sign, that's why it didn't work

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

this should do it.

ajor
ajor
8,216 Points
ajor
ajor
8,216 Points

Oh, I see! Thank you so much, William!