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

Posted by Frank Tocci
Frank Tocci
2,316 Points

Not sure how to initialize key-value pairs

It wants me to allocate memory and initialize the key value pairs, but I can't find the proper way to do so. Thanks in advance.

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

1 Answer

Anjali Pasupathy
Anjali Pasupathy
28,883 Points
Anjali Pasupathy
Anjali Pasupathy
28,883 Points

You're almost there! Your alloc is correct; you just need to correct the format you're using to initialize the NSMutableDictionary.

The general format for allocating and initializing an NSMutableDictionary object can look like this:

NSMutableDictionary *carDict = [[NSMutableDictionary alloc] initWithObjectsAndKeys: /*OBJECT 1*/, /*KEY 1*/, /*OBJECT 2*/, /*KEY 2*/, nil];

In this case, OBJECT 1 would be @"Honda", KEY 1 would be @"Make", OBJECT 2 would be @"Accord", and KEY 2 would be @"Model".

I hope this helps!

Frank Tocci
Frank Tocci
2,316 Points

Worked like a charm. Thanks.