How to save NSMutablearray in NSUserDefaults

Question

I have two NSMutableArray\'s. They consist of images or text. The arrays are displayed via a UITableView. When I kill the app the data within the <

Answer 1

Do you really want to store images in property list? You can save images into files and store filename as value in NSDictionary.

define path for store files

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
self.basePath = [paths firstObject];

Store and load image:

- (NSString *)imageWithKey:(NSString)key {
    NSString *fileName = [NSString stringWithFormat:@"%@.png", key]
    return [self.basePath stringByAppendingPathComponent:fileName];
}

- (void)saveImage:(UIImage *)image withKey:(NSString)key {
    NSData *imageData = UIImagePNGRepresentation(image);
    [imageData writeToFile:[self imageWithKey:key] atomically:YES];
}

- (UIImage *)loadImageWithKey:(NSString)key { {
    return [UIImage imageWithContentsOfFile:[self imageWithKey:key]];
}

And you can store path or indexes in NSMutableDictionary

- (void)saveDictionary:(NSDictionary *)dictionary {
    NSMutableDictionary *dictForSave = [@{ } mutableCopy];
    for (NSString *key in [dictionary allKeys]) {
        [self saveImageWithKey:key];
        dictForSave[key] = @{ @"image" : key };
    }
    [[NSUserDefaults standardUserDefaults] setObject:dictForSave forKey:@"MyDict"];
}

- (NSMutableDictionary *)loadDictionary:(NSDictionary *)dictionary {
    NSDictionary *loadedDict = [[NSUserDefaults standardUserDefaults] objectForKey:@"MyDict"];
    NSMutableDictionary *result = [@{ } mutableCopy];
    for (NSString *key in [loadedDict allKeys]) {
        result[key] = [self imageWithKey:key];
    }
    return result;
}

In NSUserDefaults you can store only simply objects like NSString, NSDictionary, NSNumber, NSArray.

Also you can serialize objects with NSKeyedArchiver/NSKeyedUnarchiver that conforms to NSCoding protocol .