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

Posted by Linus Hallberg
Linus Hallberg
845 Points

i don't understand this, what should i do?

i don't know how I'm going further with this.

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

2 Answers

Ahmet GULER
Ahmet GULER
7,181 Points
Ahmet GULER
Ahmet GULER
7,181 Points

Hello,

I have the same problem.. please help. Can't get through the challenge. challenge says: 'Do this all in one line of code.'

please if someone can give also an example of both 1 line of code. and also 3 lines of code variant..

Here what i have tried and failed:

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

error was:

expected ']' NSMutableDictionary *carDict = [NSMutableDictionary alloc] initWithObjectsAndKeys: @"Make":@"Honda", @"Model":@"Accord", nil];; ^ 1 error generated.

another variant i also couldn't pass through preview is:

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

//In the video it writes test for testDict. so, i wrote car for carDict

error was:

use of undeclared identifier 'car' [car initWithObjectsAndKeys: @"Make":@"Honda", @"Model":@"Accord", nil]; ^ 1 error generated.

i removed the car.. this time error was :

use of undeclared identifier 'initWithObjectsAndKeys' [initWithObjectsAndKeys: @"Make":@"Honda", @"Model":@"Accord", nil]; ^ 1 error generated.

please help to understand

ARMANDO RODRIGUEZ
ARMANDO RODRIGUEZ
4,216 Points
ARMANDO RODRIGUEZ
ARMANDO RODRIGUEZ
4,216 Points

Okay guys, I figured it out and it's stupid and they should fix it.
For some reason, Make:Honda and Model:Accord are reversed. Model:Accord should be the first object in the dictionary. 

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

That will past first question.

NSString *myRide = [[NSString alloc] init];

This will past second question. You need to allocate and initialize but do not declare a value for the string.

myRide = [carDict valueForKey:@"Model"];

This will pass third question because you are telling it to assign the value of the key "Model" to the string you already allocated, myRide. You don't need to put a pointer again because the pointer was already declared.