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

Ryan Bartusek
Ryan Bartusek
5,999 Points

How to add an array of items into an NSMutableDictionary with an already declared array for the values.

I'm having a very hard time figuring out the syntax to use objectAtIndex to load an NSMutableDictionary.. this is what I found on stack overflow, but I'm not getting something..

variable_assignment.mm
NSArray *shoeOrder = @[@"Charles Smith", @(9.5), @"loafer", @"brown"];

NSMutableDictionary *shoeOrderDict= [[NSMutableDictionary alloc] init];

2 Answers

You're first two lines are correct for Tasks 1 and 2. For Task 3 they want you to fill the dictionary with values from the array:

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

Of course, there are other ways to do this. E.g., using a loop. But this works too.

Ryan Bartusek
Ryan Bartusek
5,999 Points

Thank you! After struggling a bit on this I appreciate you taking the time. :)

You are welcome. Happy coding!