Question

I’m trying to return a NSMutableArray from my block in my method, but when I add the line return [responseString JSONValue];, I get some compiler warnings.

- (NSMutableArray*)getTodayData:(NSDate*)today
{
        ASIFormDataRequest *request = [[[ASIFormDataRequest alloc] initWithURL:url] autorelease];
        [request setPostValue:[dateFormat stringFromDate:today] forKey:@"target_date"];
        NSError *error = [request error];

        [request setCompletionBlock:^{
            NSString *responseString;
            if (!error) {
                responseString = [request responseString];
                return [responseString JSONValue];
            } else {
                NSLog(@"error: %@", error);
            }
        }];
        [request setFailedBlock:^{
            NSString *responseString;
            if (!error) {
                responseString = [request responseString];
            } else {
                NSLog(@"error: %@", error);
            }
        }];
        [request startAsynchronous];
}

Answer 1

The setCompletionBlock: and setFailedBlock: methods in ASIFormDataRequest do not accept blocks with a return value. You need to restructure your code so that there is no return value.

For example:

- (void)viewDidLoad
{
  [self getTodayData:self.datePicker.date];
}

- (void)getTodayData:(NSDate*)today
{
      self.appointmentsArray = [NSArray array]; // set it to an empty value now, so the table view displays nothing

      ASIFormDataRequest *request = [[[ASIFormDataRequest alloc] initWithURL:url] autorelease];
      [request setPostValue:[dateFormat stringFromDate:today] forKey:@"target_date"];
      NSError *error = [request error];

      [request setCompletionBlock:^{
          NSString *responseString;
          if (!error) {
              responseString = [request responseString];
              self.appointmentsArray = [responseString JSONValue];

              [self.appointmentsArrayTableView reloadData]; // I'm assuming you want to display the appointments in some view
          } else {
              NSLog(@"error: %@", error);
          }
      }];
      [request setFailedBlock:^{
          NSString *responseString;
          if (!error) {
              responseString = [request responseString];
          } else {
              NSLog(@"error: %@", error);
          }
      }];
      [request startAsynchronous];
}