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

Mikhail Bliznyuk
Mikhail Bliznyuk
8,893 Points
Posted by Mikhail Bliznyuk
Mikhail Bliznyuk
8,893 Points

Now add the values in our array to our new dictionary.

Now add the values in our array to our new dictionary. The keys for the values should be: 'customer', 'size', 'style' and 'color'. The values in the original array are in the same order as the keys listed above. (Note: Don't set the values directly as strings, but rather use something like 'objectAtIndex' to reference the original array.)

I am confused here. Don't know what to do, I have already tried almost everything. Could someone help? I really appreciate, thank you!

variable_assignment.mm 
NSArray *shoeOrder = [[NSArray alloc] initWithObjects: @"Charles Smith", @(9.5), @"loafer", @"brown", nil];
NSMutableDictionary *shoeOrderDict = [[NSMutableDictionary alloc] init];

2 Answers

Steve Hunter
Steve Hunter
57,712 Points

Hi Mikhail,

You've got the first two lines spot on! Next, you want to use setObject: forKey to populate your dictionary. Access the array using objectAtIndex:. Here's one line - you should be OK to work the rest out from there. 

NSArray *shoeOrder = [[NSArray alloc] initWithObjects: @"Charles Smith", @(9.5), @"loafer", @"brown", nil];
NSMutableDictionary *shoeOrderDict = [[NSMutableDictionary alloc] init];
[shoeOrderDict setObject:[shoeOrder objectAtIndex:0] forKey:@"customer"];

Let me know how you get on.

Steve.

Steve Hunter
Steve Hunter
57,712 Points

No problem! :+1:

Ibrahim Al-Khalidi
Ibrahim Al-Khalidi
414 Points
Ibrahim Al-Khalidi
Ibrahim Al-Khalidi
414 Points

what about this way ?

NSArray *shoeOrder = [[NSArray alloc] initWithObjects: @"Charles Smith",[NSNumber numberWithDouble: 9.5], @"loafer" ,@"brown", nil];

NSMutableDictionary *shoeOrderDict = [[NSMutableDictionary alloc] initWithObjectsAndKeys: @"[objectAtIndex:0 in shoeOrder]", @"customer", @"[objectAtIndex:1 in shoeOrder]" , @"size", @"[objectAtIndex:2 in shoeOrder]", @"style",@"[ objectAtIndex:3 in shoeOrder]",@"color", nil];

Bummer! It looks like at least one of your key/value pairs is incorrect. Check them carefully for syntax and spelling.