App crashes when storing NSArray in NSUserDefaults

Question

I couldn't store an NSArray in NsUserDefaults. The app gets crashed
in this line [savedData setObject:jsonValue forKey:@"JSONDATA"];

Below is my code. and i have mention my log error below

NSArray *jsonValue =[NSJSONSerialization JSONObjectWithData:data options:0 error:nil];
NSUserDefaults *savedData = [NSUserDefaults standardUserDefaults];
[savedData setObject:jsonValue forKey:@"JSONDATA"];
[savedData synchronize];

Error log:

*** Terminating app due to uncaught exception '`NSInvalidArgumentException`', reason: '*** -

[NSUserDefaults setObject:forKey:]: attempt to insert non-property list object <CFBasicHash 0x8c62b10 [0x1d2aec8]>{type = immutable dict, count = 3,
    entries =>

Answer 1

Yes they can not be saved like this in NSUserDefaults.

I am writing a code below please have a look and for more study go look apple docs okay.

Code is here:

//For Saving

NSData *dataSave = [NSKeyedArchiver archivedDataWithRootObject:yourArrayToBeSave]];
[[NSUserDefaults standardUserDefaults] setObject:dataSave forKey:@"array"];

[[NSUserDefaults standardUserDefaults] synchronize]; // this will save you UserDefaults

//For retrieving

NSData *data = [[NSUserDefaults standardUserDefaults] objectForKey:@"array"];
NSArray *savedArray = [NSKeyedUnarchiver unarchiveObjectWithData:data];

Answer 2

While kshitij's answer is correct, sadly, it doesn't end there. If you want to save custom objects inside your NSUserDefaults, your custom object has to implement the NSCoding protocol and override the initWithCoder and encodeWithCoder methods. An example of such can be like:

@interface Book : NSObject <NSCoding>
@property NSString *title;
@property NSString *author;
@property NSUInteger pageCount;
@property NSSet *categories;
@property (getter = isAvailable) BOOL available;
@end

@implementation Book

#pragma mark - NSCoding

    - (id)initWithCoder:(NSCoder *)decoder {
        self = [super init];
        if (!self) {
            return nil;
        }

        self.title = [decoder decodeObjectForKey:@"title"];
        self.author = [decoder decodeObjectForKey:@"author"];
        self.pageCount = [decoder decodeIntegerForKey:@"pageCount"];
        self.categories = [decoder decodeObjectForKey:@"categories"];
        self.available = [decoder decodeBoolForKey:@"available"];

        return self;
    }

    - (void)encodeWithCoder:(NSCoder *)encoder {
        [encoder encodeObject:self.title forKey:@"title"];
        [encoder encodeObject:self.author forKey:@"author"];
        [encoder encodeInteger:self.pageCount forKey:@"pageCount"];
        [encoder encodeObject:self.categories forKey:@"categories"];
        [encoder encodeBool:[self isAvailable] forKey:@"available"];
    }

@end

Answer 3

try like this

 NSMutableArray *jsonValue =[NSJSONSerialization JSONObjectWithData:data options:0 error:nil];
    NSData *yourEncodedObject = [NSKeyedArchiver archivedDataWithRootObject: jsonValue];

       NSUserDefaults *savedData = [NSUserDefaults standardUserDefaults];
        [userData setObject: yourEncodedObject forKey:@"JSONDATA"];
    [savedData synchronize];