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

Posted by alexanderliddiard
alexanderliddiard
1,054 Points

no clue what im doing wrong plz help

says remember to use self

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];

    // Add your code below!
    self.shoppingList.text = [shoppingList objectsAtIndex:@"toothpaste", @"bread", @"eggs"];
}

@end

1 Answer

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

Hey there!

self.shoppingList.text = [shoppingList objectsAtIndex:@"toothpaste", @"bread", @"eggs"]

An NSArray has no property or method called text. XCode will warn you right away. You have declared shoppingList in your header file, so lets use it directly, withouttext`

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

But before we can use an NSArray we always have to initialize it first! The method you are using here is not for initializing an array, but for retrieving items from an already initialized array (though the syntax is not correct, but that would be too much for now...).

The initializer you are looking for is initWithObjects You can find this method and all other initializers in the Apple Developer Docs.

Let's give it a try:

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

The initWithObjects initializer needs a nil as the last value, so it knows when you are finished adding your items. As mentioned before, the docs show you more options to initialize an array, so flick through it a bit.

Hope that helps!