Objective C - Table View: load items from database - objective-c

Question

I have a table view and until now I fill the table with spelled numbers like this:
- (NSMutableArray *)data {
if(!_data){
_data = [[NSMutableArray alloc] init];
// spelled numbers
NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init];
formatter.numberStyle = NSNumberFormatterSpellOutStyle;
for(int i = 0; i < 20; i++){
NSNumber *thisNumber = [NSNumber numberWithInt:i];
NSString *spelledOutNumber = [formatter stringFromNumber:thisNumber];
[_data addObject:spelledOutNumber];
}
}
return _data;
}
But how can I fill the table now with dynamic items from a database?
This is how I get the data from database:
NSURLSession *session = [NSURLSession sharedSession];
NSString *url = [NSString stringWithFormat:#"http://www.example.net/iOS/game/getData.php"];
NSURLSessionDataTask *dataTask = [session dataTaskWithURL:[NSURL URLWithString:url] completionHandler:^(NSData *data, NSURLResponse *response, NSError *error){
NSDictionary *json = [NSJSONSerialization JSONObjectWithData:data options:0 error:nil];
NSString *errorCode = [json valueForKey:#"error"];
if([errorCode isEqualToString:#"e0"]){
NSArray *jsondata = [json objectForKey:#"data"];
for (int i = 0; i < [jsondata count]; i++) {
NSString *name = [[jsondata objectAtIndex:i] objectForKey:#"name"];
[_data addObject:name];
}
}
}];
[dataTask resume];
But how can I load this data now to the table view? If I just put the database code to the data method it doesnt work, because the database code is asynchron. Can someone help me with it?
Edit:
Here are the data methods:
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return [self.data count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:#"cell" forIndexPath:indexPath];
cell.textLabel.text = [self.data objectAtIndex:indexPath.row];
return cell;
}