Save data with NSUserDefaults

Question

I create a quiz game. Here is a part of my code:

- (void) viewDidLoad
{
logos = [[NSMutableArray alloc] init];
[logos addObject:@"adidas"];
[logos addObject:@"nike"];
[logos addObject:@"puma"];

[self showLogo];
}

int currentQuestionIndex;

- (void) showLogo
{

currentQuestionIndex++;

NSString *question = [logos objectAtIndex:currentQuestionIndex];

[_questionImage setImage:[UIImage imageNamed:question]];

...

}

If user will choose the right answer, "showLogo" will be called again to go to next question. So, Level is completed.

Everything works great.

Please help me to save the information/levels. IF level is completed, when user Launch game he have to start with saved level.

This is what I tried already:

- (void) checkAnswer
{

///... if user answered right

[[NSUserDefaults standardUserDefaults] setInteger:currentQuestionIndex forKey:@"currentLevel"];

[self showLogo];
/// so, I tried to save "currentQuestionIndex" forKey currentLevel, and call "showLogo"
}

and here is modified "showLogo"

- (void) showLogo
{

int savedLevel = [[NSUserDefaults standardUserDefaults] integerForKey:@"currentLevel"];

currentQuestionIndex = savedLevel+1 ;

NSString *question = [logos objectAtIndex:currentQuestionIndex];

[_questionImage setImage:[UIImage imageNamed:question]];

...

}

but doesn't work.. using this method, I tried to save score, and it works also..

Help please. Thanks

score 1 · Answer 1 · answered Mar 05 '13 at 03:03

1

As stated in the documentation, you cannot save a primitive (int) into NSUserDefaults. You will have to turn your int into a NSNumber before you can save it, by doing something like this:

NSNumber *questionIndex = [[NSNumber alloc] numberWithInt:currentQuestionIndex];

Then, when you load it back, if you need an int again you can use intValue

answered Mar 05 '13 at 03:03

Ares

5,905
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I tried the code in my answer, and it works. – tolgamorf Mar 05 '13 at 03:08
I think the problem is in my lines. It works, but when I re-launch app, every time my level increases without to answer question. :) So, my NSUserDefaults saves the current level. When I re-launch app, my code will read NSUserDefaults++, and Automatically go to the next level, and also save the current level and again... – Mary Torh Mar 05 '13 at 03:18

score 0 · Answer 2 · answered Mar 05 '13 at 03:02

0

After setting a key-value in NSUserDefaults, you have to save it using the synchronize method.

[[NSUserDefaults standardUserDefaults] setInteger:currentQuestionIndex forKey:@"currentLevel"];
[[NSUserDefaults standardUserDefaults] synchronize];

answered Mar 05 '13 at 03:02

tolgamorf

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23

Save data with NSUserDefaults

2 Answers2