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iOS

Alloc and init

For the challenge alloc and init:

"Create an NSMutableDictionary called 'carDict'. Allocate memory and initialize 'carDict' with the following key/value pairs: "Make":"Honda", "Model":"Accord". Do this all in one line of code."

why is my first code wrong and second correct? why should I write "Honda" and "Accord" in front of "Make" and "model"?

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


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

2 Answers

Hi Kirhim,

Not sure what you're asking exactly; that's just how the method signature goes for that method in Objective-C. See the docs.

In the code challenge it's in the order of "Make":"Honda", "Model":"Accord".

But when I write the in the code, why should I write in the order of "@"Honda", @"Make", @"Accord", @"Model"?

I hope you get what I am trying to say.

Yeah I get what you're saying — the ordering of the parameters for that method is a bit unconventional. But, the answer to your question is: "because that's just the way it works." Such is Objective-C syntax.

I see thanks!