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iOS

Posted by Lachlan Dawson
Lachlan Dawson
10,007 Points

Photo Bombers app crashing when device is not connected to network

Hi

I'm building the Photo Bombers app but have ran into a problem where the app crashes when the device is not connect to a network. I think the problem is in this bit of code

    if (self.accessToken == nil) {
        [SimpleAuth authorize:@"instagram" options:@{@"scope": @[@"likes"]} completion:^(NSDictionary *responseObject, NSError *error) {

            self.accessToken = responseObject[@"credentials"][@"token"];

            [userDefaults setObject:self.accessToken forKey:@"accessToken"];
            [userDefaults synchronize];

            [self refresh];
        }];
    } else {

[self refresh];

     }

I believe that it is crashing in the else {[self refresh];} and I have tried to replace it with an alert but when I open the app only the alert shows up (even if connect to network).

Any help would be great! thank you

Lachlan Dawson
Lachlan Dawson
10,007 Points

Sam Soffes Amit Bijlani Would you guys know how to fix this problem?

2 Answers

kerdeseverin
kerdeseverin
9,688 Points
kerdeseverin
kerdeseverin
9,688 Points

If its crashing then it might be because one of your objects is nil. 

responseObject[@"credentials"][@"token"]

Since the connection was lost and no data was received, does responseObject have a value?

salem mohamed
salem mohamed
577 Points
salem mohamed
salem mohamed
577 Points

i have the same problem, the app keeps crashing when the user cancel instagram login ANY fix?

UINavigationBar *navigationBar = navigationController.navigationBar;
navigationBar.barTintColor = [UIColor colorWithRed:232.0 / 255.0 green:129.0 / 255.0 blue:91.0 / 255.0 alpha:1.0];
navigationBar.barStyle = UIBarStyleBlackOpaque;
navigationBar.tintColor = [UIColor whiteColor];
[self.collectionView registerClass:[THPhotoCell class] forCellWithReuseIdentifier:@"photo"];
self.collectionView.backgroundColor = [UIColor blackColor];
NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
self.accessToken = [userDefaults objectForKey:@"accessToken"];

if (self.accessToken == nil) {
    [SimpleAuth authorize:@"instagram" options:@{@"scope": @[@"likes"]} completion:^(NSDictionary *responseObject, NSError *error) {

        self.accessToken = responseObject[@"credentials"][@"token"];

        [userDefaults setObject:self.accessToken forKey:@"accessToken"];
        [userDefaults synchronize];

        [self refresh];
    }];
} else {
    [self refresh];
}
[self refresh];

[self refresh];}

  • (void)refresh { if (self.loading) { return; }

    self.loading = YES;

    NSURLSession *session = [NSURLSession sharedSession];

    // You can change the hashtag here to make your very own photo browser app! NSString *urlString = [[NSString alloc] initWithFormat:@"https://api.instagram.com/v1/tags/photobomber/media/recent?access_token=%@&count=500", self.accessToken];

    NSURL *url = [[NSURL alloc] initWithString:urlString]; NSURLRequest *request = [[NSURLRequest alloc] initWithURL:url]; NSURLSessionDownloadTask *task = [session downloadTaskWithRequest:request completionHandler:^(NSURL *location, NSURLResponse *response, NSError *error) {

    NSData *data = [[NSData alloc] initWithContentsOfURL:location];
NSDictionary *responseDictionary = [NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:nil];

self.photos = [responseDictionary valueForKeyPath:@"data"];

dispatch_async(dispatch_get_main_queue(), ^{
    [self.collectionView reloadData];
    self.loading = NO;
});

    }]; [task resume]; }