Getter & setter int value (NSObject) not passing from one ViewController to another - ios

Question

I'm building a game with 3 different level difficulties (Easy, Medium, & Delete) I have 2 ViewControllers and 1 NSObject class that I'm using to set and get the game difficulty value (0=easy, 1=Medium, 2=Delete(hard). Within context of how I'm doing it, I've research and tried many variations with no success. NOTE: I have tried to code this, but have since stripped out that part of the code because it wasn't working. I'm somewhat familiar with NSUserDefaults, so if that's a better solution, please advise. I may need a little direction on setting that up, though.
- ViewController 1 (RewindSettingsViewController): I have 3 buttons: Easy, Medium, Delete. User taps button, they go to ViewController 2
- ViewController 2 (RewindGameViewController): This is the actual game with a Start button. This is where I'm hung up; getting the difficulty passed into this view.
CODE:
.h - GameManager : NSObject
+(void) setDifficulty:(int)difficulty;
+(int) getDifficulty;
.m - GameManager
static int _difficulty;
+(void)setDifficulty:(int)difficulty {
_difficulty = difficulty;
}
+(int)getDifficulty {
return _difficulty;
}
(VC1) .h - RewindSettingsViewController : UIViewController
#property (nonatomic, strong) IBOutlet UIButton *easyModeButton;
#property (nonatomic, strong) IBOutlet UIButton *mediumModeButton;
#property (nonatomic, strong) IBOutlet UIButton *hardModeButton;
-(IBAction)easyMode;
-(IBAction)mediumMode;
-(IBAction)hardMode;
.m - RewindSettingsViewController
-(IBAction)easyMode {
[GameManager setDifficulty:0];
}
-(IBAction)mediumMode {
[GameManager setDifficulty:1];
}
-(IBAction)hardMode {
[GameManager setDifficulty:2];
}
(VC2) .h - RewindGameViewController : UIViewController
no code here for difficulty settings
.m - RewindGameViewController
At this point, _difficulty is of course still nil. My question marks below are my pain points
?: How to get the difficulty value stored in "setDifficulty" into "getDifficulty (_difficulty)" and properly call it in the IF statement?
?: I'm thinking _difficulty should be in the IF statements, but with everything I'm trying, syntax keeps barking at me.
-(void)placeObjectsRewind {
randomTopObjectRewind = arc4random() %350;
randomTopObjectRewind = randomTopObjectRewind - 228;
if (?) {
randomBottomObjectRewind = randomTopObjectRewind + 700; //LEVEL DIFFICULTY: EASY
objectTopRewind.center = CGPointMake(0, randomTopObjectRewind);
objectBottomRewind.center = CGPointMake(0, randomBottomObjectRewind);
} else if (?) {
randomBottomObjectRewind = randomTopObjectRewind + 665; //LEVEL DIFFICULTY: MEDIUM
objectTopRewind.center = CGPointMake(0, randomTopObjectRewind);
objectBottomRewind.center = CGPointMake(0, randomBottomObjectRewind);
} else if (?) {
randomBottomObjectRewind = randomTopObjectRewind + 635; //LEVEL DIFFICULTY: DELETE (HARD)
objectTopRewind.center = CGPointMake(0, randomTopObjectRewind);
objectBottomRewind.center = CGPointMake(0, randomBottomObjectRewind);
}
}

Answer 1

Instead of
static int _difficulty;
type this into your GameManager.h
#property int difficulty;
You don't have to write the Setter and Getter by yourself, the property-statement do this for you. The Getter/Setter is stored in the instance of GameManager you use. So get the instance of you GameManager and there you set like this:
[MyGameManagerInstance setDifficulty:0];
and get like
[MyGameManagerInstance difficulty];
Due to the fact that the difficulty-property is in the .h file, it's part of the Class's API which you can access from other ViewController or Classes.
EDIT:
Like you said, you could do this also with the NSUserDefaults. Just put it in like this:
[[NSUserDefaults standardUserDefaults] setInteger:1 forKey:#"Difficulty"];
and get it like this:
int myInt = [[NSUserDefaults standardUserDefaults] integerForKey:#"Difficulty"];

Answer 2

Since you've made the methods you want to use class methods, the syntax is going to be similar to if ([GameManager getDifficulty] == 0) etc.
(As a style point, you would usually drop the "get" in Objective-C and just name the method to return a value difficulty.)