CODEWITHSUNDEEP
iosobjective-cnsuserdefaultsnsmutabledictionary
Brandon
Brandon

Reputation: 75

Saving objects to the app, IOS

My app in development is related to survey questions. (fun ones, not boring ones!) I want to create a tier system for each question relative to the user, each time they answer a specific question I want to associate a value to that question for that user, identifying how many times they've answered it.

I believe the way I need to achieve this is NSMutableDictionary and NSUserDefaults. This is a simplified version of my code:

NSMutableDictionary *questionTierDictionary = [[NSMutableDictionary alloc]init];

[[NSUserDefaults standardUserDefaults] objectForKey:@"questionTiers"];

[questionTierDictionary setObject:[NSNumber numberWithInt:4] forKey:@(2)];


[[NSUserDefaults standardUserDefaults] synchronize];

NSLog(@"%@", questionTierDictionary);

Does this code save this data indefinitely to the app, or does it disappear once the user has closed the app? If so, do you have any suggestions on how I can easily test to see if the data was stored?

Upvotes: 1

Views: 65

Answers (2)

Steven Gardner
Steven Gardner

Reputation: 234

sandbox path ：

~~ Documents:

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *docDir = [paths objectAtIndex:0];

~~~ Caches:

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES); NSString *cachesDir = [paths objectAtIndex:0];

~~~ tmp:

NSString *tmpDir = NSTemporaryDirectory();

~~~ home sandbox:

NSString *homeDir = NSHomeDirectory();

~~~ for pic :

NSString *imagePath = [[NSBundle mainBundle] pathForResource:@"apple" ofType:@"png"];
UIImage *appleImage = [[UIImage alloc] initWithContentsOfFile:imagePath];

Example:

NSFileManager* fm=[NSFileManager defaultManager];
if(![fm fileExistsAtPath:[self dataFilePath]]){
    //
    [fm createDirectoryAtPath:[self dataFilePath] withIntermediateDirectories:YES attributes:nil error:nil];

    //
    NSArray *files = [fm subpathsAtPath: [self dataFilePath] ];

    //
    NSData *data = [fm contentsAtPath:[self dataFilePath]];

    //
    NSData *data = [NSData dataWithContentOfPath:[self dataFilePath]];
}

I hope I could help you!

Upvotes: 1

Divyanshu Sharma
Divyanshu Sharma

Reputation: 561

NSUserDefaults save data permanently in you application directory till you remove it manually... to save a object in NSUserDefaults code like this

NSDictionary *dict = [NSDictionary dictionaryWithObjectsAndKeys:@"yourObject",@"yourKey", nil];

[[NSUserDefaults standardUserDefaults]setObject:dict forKey:@"dict"];

//fetch Like this

NSDictionary *dict1 = [[NSUserDefaults standardUserDefaults] objectForKey:@"dict"];

Upvotes: 0

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