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tableviewnsurlsessionnsjsonserializationnsurlsessiondatatask

NSJSONSerialization Not Getting Called - Objective C


I am trying to populate the TableViewCells in my TableViewContoller with an Array of data that is being pulled from a JSON object. NSJSONSerialization is simply not getting called.

I've tried a variety of things using DataTaskWithURL. Sadly I'm coming up empty with 0 items found in the array. Thanks in advance for anyone's help!

@property NSArray *toothpastes;

@end

@implementation ToothpastChoicesTableViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    NSString *urlString = @"https://s3.amazonaws.com/mmios8week/toothpastes.json";
    NSURLSession *session = [NSURLSession sharedSession];

    [session dataTaskWithURL:[NSURL URLWithString:urlString] completionHandler:^
     (NSData *data,
      NSURLResponse *response,
      NSError *error) {

      if (error) {
         NSLog(@"%@", error);
     } else {

    self.toothpastes = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingAllowFragments error:&error];
    [self.tableView reloadData]; }

    }];
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {

    NSLog(@"%lu", (unsigned long)self.toothpastes.count);

    return self.toothpastes.count;
}


- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"CellID" forIndexPath:indexPath];

    cell.textLabel.text = self.toothpastes[indexPath.row];

    return cell;
}

Solution

  • You forgot to resume the task

    NSURLSessionDataTask *task = [session dataTaskWithURL:[NSURL URLWithString:urlString] completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
    
        if (error) {
          NSLog(@"%@", error);
        } else {
    
         self.toothpastes = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingAllowFragments error:&error];
         [self.tableView reloadData]; 
        }
      }];
    [task resume];