How to display contacts in tableview - Objective C

Question

I want to create program that will import contacts from adressbook and show them in tableview. I already did code to download contacts from adressbook but when I'm adding them into Array and then trying to show in TableView they don't appear when I'm starting app. Here's code:

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
    [self getPersonOutOfAddressBook];
    [super viewDidLoad];


    // Do any additional setup after loading the view, typically from a nib.
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return [self.tableData count];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *cellIdentifier = @"Identifier";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];

    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
    }

    Person *person = [self.tableData objectAtIndex:indexPath.row];
    cell.textLabel.text = person.fullName;

    return cell;
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {

}
- (void)getPersonOutOfAddressBook
{
    //1
    CFErrorRef error = NULL;
    ABAddressBookRef addressBook = ABAddressBookCreateWithOptions(NULL, &error);
    __block BOOL accessGranted = NO;

    if (ABAddressBookRequestAccessWithCompletion != NULL) { // We are on iOS 6
        dispatch_semaphore_t semaphore = dispatch_semaphore_create(0);

        ABAddressBookRequestAccessWithCompletion(addressBook, ^(bool granted, CFErrorRef error) {
            accessGranted = granted;
            dispatch_semaphore_signal(semaphore);
        });
    }
    if (addressBook != nil) {
        NSLog(@"Succesful.");

        //2
        NSArray *allContacts = (__bridge_transfer NSArray *)ABAddressBookCopyArrayOfAllPeople(addressBook);

        //3
        NSUInteger i = 0; for (i = 0; i < [allContacts count]; i++)
        {
            Person *person = [[Person alloc] init];
            ABRecordRef contactPerson = (__bridge ABRecordRef)allContacts[i];

            //4
            NSString *firstName = (__bridge_transfer NSString *)ABRecordCopyValue(contactPerson,
                                                                                  kABPersonFirstNameProperty);
            NSString *lastName = (__bridge_transfer NSString *)ABRecordCopyValue(contactPerson, kABPersonLastNameProperty);
            NSString *fullName = [NSString stringWithFormat:@"%@ %@", firstName, lastName];

            person.firstName = firstName; person.lastName = lastName;
            person.fullName = fullName;

            [self.tableData addObject:person];
        }

        //8
        CFRelease(addressBook);
    } else { 
        //9
        NSLog(@"Error reading Address Book");
    } 
}
- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

When I'm using debugger it shows that variables firstname, lastname and then fullname have access to adressbook because I can see name or last name of person. But I think there is problem with adding to array because I can't see anything in this array. Could someone help me? I'm beginner with Objective - C so please forbearance :)

Answer 1

To use an array you need to both declare it and create it. You do this by allocating and initializing the array.

self.tableData = [[NSMutableArray alloc] init];