iOS: Core Data

File > New Project > Empty Application
Select "Core Data" checkbox

".xcdatamodeld" file created in project

select data model file, "Add Entity" at bottom left corner
"Add attributes" using the "+" sign

File > New File > Core Data > NSManagedObject
Select data model, and entity to create the NS managed object
.h and .m created in project

File > New File > UIViewController

AppDelegate.h (add View controller )

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions

{

    self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];

    // Override point for customization after application launch.

    self.window.backgroundColor = [UIColor whiteColor];

    // ADDED

    StartVC *vc = [[StartVC alloc] initWithNibName:@"StartVC" bundle:nil];

    // ADDED

    self.window.rootViewController = vc;

    // ADDED

    [vc release];

    

    [self.window makeKeyAndVisible];

    return YES;

}

VC .m

for adding/inserting data 

- (void)viewDidLoad

{

    [super viewDidLoad];

    // Do any additional setup after loading the view from its nib.

    

    AppDelegate *ad = [[UIApplication sharedApplication] delegate];

    Property *prop = (Property *)[NSEntityDescription insertNewObjectForEntityForName:@"Property" inManagedObjectContext:ad.managedObjectContext];

    prop.name = @"Sengkang";

    prop.seller = @"Beng";

    prop.price = (NSDecimalNumber *)[NSDecimalNumber numberWithInt: 100000];

    prop.address = @"123, Anchorvale #01-01";

    

    NSError *err;

    if(![ad.managedObjectContext save:&err])

        NSLog(@"error %@", [err domain]);

    else

        NSLog(@"Data added");

}

for reading data

// reading

    NSEntityDescription *desc = [NSEntityDescription entityForName:@"Property" inManagedObjectContext:ad.managedObjectContext];

    NSFetchRequest *req = [[NSFetchRequest alloc] init];

    [req setEntity:desc];

    

    NSArray *obj = [ad.managedObjectContext executeFetchRequest:req error:&err];

    

    for(Property *p in obj)

    {

        NSLog(@"-------------");

        NSLog(@"Property name: %@", p.name);

        NSLog(@"Price: %f", p.price.floatValue);

        NSLog(@"Seller: %@", p.seller);

    }