Can't overwrite custom Saved Object in NSuserDefaults

[subharb]

Hello guys,

Im willing to overwrite a custom object in NSUserDefault, it's a Matrix.
It works fine the first time I create the object and save it, but it never updates.

here's the code:
The modification to the Matrix Class

- (void)encodeWithCoder:(NSCoder *)encoder
{
	//Encode properties, other class variables, etc
    [encoder encodeObject:self.matriz forKey:@"matriz"];
}
- (id)initWithCoder:(NSCoder *)decoder
{
    self = [super init];
    if( self != nil )
    {
		//decode properties, other class vars
        self.matriz = [decoder decodeObjectForKey:@"matriz"];
    }
    return self;
}

The methods that I use in a ViewController to set up a Matrix Object named "horarios"
I want to create a new Matrix if it's the very first time I execute this ViewController or then load the previous one.

-(void)viewDidLoad(){
	if([self loadCustomObjectWithKey:@"horarios"] == nil){
		//Inicializar el horarios a 0, que es lo que vale al inicio
		self.horarios = [[Matriz alloc]init:(int)3 column:5];		
	}
	else{
		self.horarios = [self loadCustomObjectWithKey:@"horarios"];		
	}

This is the code that saves and loads the customObject from NSUserDefaults in the ViewController

-(void)saveCustomObject:(Matriz*)obj
{
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
	NSData *myEncodedObject = [NSKeyedArchiver archivedDataWithRootObject:obj];
	
	//[obj showValue];
	
    [defaults setObject:myEncodedObject forKey:@"horarios"];
}

-(Matriz*)loadCustomObjectWithKey:(NSString*)key{
	
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    NSData *myEncodedObject = [defaults objectForKey: key];
    Matriz* obj = (Matriz*)[NSKeyedUnarchiver unarchiveObjectWithData: myEncodedObject];
	
	return obj;
}

The code works fine the first time, when in NSUserDefaults there's no custom object, when I save it saves the current status of the matrix, but the next times, when there already an object if always loads the previous one, as if it could only save once the object.

I dont understand it, any ideas?

[baja_yu]

You aren't synchronizing defaults after you call setObject.

[subharb]

Originally Posted by baja_yu

You aren't synchronizing defaults after you call setObject.

Thanks, but how can I do that?

[baja_yu]

By calling 'synchronize'

[subharb]

Originally Posted by baja_yu

By calling 'synchronize'

Thanks, that is

[[NSUserDefaults standardUserDefaults] synchronize];

[Duncan C]

Originally Posted by subharb

Hello guys,

Im willing to overwrite a custom object in NSUserDefault, it's a Matrix.
It works fine the first time I create the object and save it, but it never updates.

here's the code:
The modification to the Matrix Class

- (void)encodeWithCoder:(NSCoder *)encoder
{
	//Encode properties, other class variables, etc
    [encoder encodeObject:self.matriz forKey:@"matriz"];
}
- (id)initWithCoder:(NSCoder *)decoder
{
    self = [super init];
    if( self != nil )
    {
		//decode properties, other class vars
        self.matriz = [decoder decodeObjectForKey:@"matriz"];
    }
    return self;
}

The methods that I use in a ViewController to set up a Matrix Object named "horarios"
I want to create a new Matrix if it's the very first time I execute this ViewController or then load the previous one.

-(void)viewDidLoad(){
	if([self loadCustomObjectWithKey:@"horarios"] == nil){
		//Inicializar el horarios a 0, que es lo que vale al inicio
		self.horarios = [[Matriz alloc]init:(int)3 column:5];		
	}
	else{
		self.horarios = [self loadCustomObjectWithKey:@"horarios"];		
	}

This is the code that saves and loads the customObject from NSUserDefaults in the ViewController

-(void)saveCustomObject:(Matriz*)obj
{
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
	NSData *myEncodedObject = [NSKeyedArchiver archivedDataWithRootObject:obj];
	
	//[obj showValue];
	
    [defaults setObject:myEncodedObject forKey:@"horarios"];
}

-(Matriz*)loadCustomObjectWithKey:(NSString*)key{
	
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    NSData *myEncodedObject = [defaults objectForKey: key];
    Matriz* obj = (Matriz*)[NSKeyedUnarchiver unarchiveObjectWithData: myEncodedObject];
	
	return obj;
}

The code works fine the first time, when in NSUserDefaults there's no custom object, when I save it saves the current status of the matrix, but the next times, when there already an object if always loads the previous one, as if it could only save once the object.

I dont understand it, any ideas?

Your encodeWithCoder method that you posted is in your Matriz class? It's trying to encode an a property "matriz" of the object. What kind of object is a "matriz"? Unless it's an object type that conforms to NSCoding, that call will fail, and not encode anything. When you try to read back an object of your Matriz class, you are going to get a nil for your matrix property.
"matriz" property.