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

Michael Lee
Michael Lee
2,855 Points
Posted by Michael Lee
Michael Lee
2,855 Points

Problem with a challenge in the "Creating a Data Model" section of the "Coding a simple app with Objective-C" course

I have a problem with Part 3 of 3 of the challenge, found at this link:

http://teamtreehouse.com/library/build-a-simple-iphone-app-with-objectivec/creating-a-data-model/creating-a-data-collection-2

The challenge is to, "in the viewDidLoad method, retrieve the string eggs from the shoppingList array and store it in shoppingCart."

However, my code (attached), does not seem to work.

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] init];
    self.shoppingList = @[@"toothpaste", @"bread", @"eggs"];
    NSString *shoppingCart = [[NSString alloc] init];
    shoppingCart = [shoppingList objectAtIndex:2];

}

@end

2 Answers

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

hey michael.

It seems to me that you created new instances of shopping cart and Shopping list inside the implementation file && tried adding the egg string to that instance. which isn't working because you made new references instead using what you already have.

In other words, you didn't have to create any new instances of shopping cart inside of your implementation file.

Simply refer to the ones you have in the header file with the self(dot) notation.

You should be good to go bro!