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iOS Object-Oriented Objective-C Memory, Arrays and Loops, Oh My! Review Dictionaries and Arrays

Kyle Melton
Kyle Melton
6,664 Points
Posted by Kyle Melton
Kyle Melton
6,664 Points

My code accomplished the task but I am not getting a success response. What gives?

I'm sure I'm just not using the exact code the app is checking for but I can't find syntax examples for "addObjectAtIndex".

variable_assignment.mm 
NSArray *shoeOrder = @[@"Charles Smith", @(9.5), @"loafer", @"brown"];
NSMutableDictionary *shoeOrderDict = [[NSMutableDictionary alloc] init];    
[shoeOrderDict setObject:shoeOrder[0] forKey:@"customer"];
[shoeOrderDict setObject:shoeOrder[1] forKey:@"size"];
[shoeOrderDict setObject:shoeOrder[2] forKey:@"style"];
[shoeOrderDict setObject:shoeOrder[3] forKey:@"color"];

2 Answers

Chase Marchione
Chase Marchione
155,055 Points
Chase Marchione
Chase Marchione
155,055 Points

Hi Kyle,

Here's a source concerning how to use the objectAtIndex instance method: https://www.techotopia.com/index.php/Working_with_Objective-C_Array_Objects#Accessing_the_Elements_of_an_Array_Object.

The syntax is '[array objectAtIndex:index]':

NSArray *shoeOrder = @[@"Charles Smith", @(9.5), @"loafer", @"brown"];
NSMutableDictionary *shoeOrderDict = [[NSMutableDictionary alloc] init];    
[shoeOrderDict setObject:[shoeOrder objectAtIndex:0] forKey:@"customer"];
[shoeOrderDict setObject:[shoeOrder objectAtIndex:1] forKey:@"size"];
[shoeOrderDict setObject:[shoeOrder objectAtIndex:2] forKey:@"style"];
[shoeOrderDict setObject:[shoeOrder objectAtIndex:3] forKey:@"color"];

Hope this helps!

Kyle Melton
Kyle Melton
6,664 Points
Kyle Melton
Kyle Melton
6,664 Points

Thank you! I was able to complete the challenge. Now my OCD of an incomplete challenge is satiated.

Janson Roberts
Janson Roberts
5,071 Points
Janson Roberts
Janson Roberts
5,071 Points

Thank you so much! This answer was the best one out of the other threads. This helps explain the process of how it works and why as well as help with the answer. =)