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iOS Object-Oriented Objective-C Memory, Arrays and Loops, Oh My! Alloc and Init

Luis Paulino
PLUS
Luis Paulino
Courses Plus Student 1,779 Points
Posted by Luis Paulino
Luis Paulino
Courses Plus Student 1,779 Points

I can't figure out my syntax error, and every time I write code my help button won't work. sorry :(. 

NSMutableDictionary *carDict;
  carDict=[NSDictionary alloc];
  [carDict initWithObjectsAndKey: @"Make":@"Honda", @"Model":@"Accord"; nil];
variable_assignment.mm

2 Answers

Addison Francisco
Addison Francisco
9,561 Points
Addison Francisco
Addison Francisco
9,561 Points

There are a few things going on with your code that should be changed. First, the challenge asks you to write it all in one line of code. Second, the message you are passing to NSMutableDictionary has a typo in it

// Change this
initWithObjectsAndKey:

// To this
initWithObjectsAndKeys:

Third, the structure of your values and keys are mixed up and you are also using colons where you shouldn't be for this init method. Here is an example from the Apple documentation on how to write this kind of initializer

NSDictionary *dict = [[NSDictionary alloc] initWithObjectsAndKeys: @"value1", @"key1", @"value2", @"key2", nil];

If you look at the order of your values and keys compared to this example, you should see that yours are backwards

// Your dictionary
@"Make":@"Honda", @"Model":@"Accord"

// Documentation example dictionary
@"value1", @"key1", @"value2", @"key2"

Now, if we put this all together, you should have something like this

NSMutableDictionary *carDict = [[NSMutableDictionary alloc] initWithObjectsAndKeys: @"Honda", @"Make", @"Accord", @"Model", nil];

Hope this was helpful for you. Be sure to always refer to the Apple Documentation :)