Add image to Tweet Sheet - iOS

Question

I am trying to add an image to a Tweet sheet in my iOS 6 app. I have one small problem. Once the user has select the image from the Photo Library, I want to then show the TweetSheet but I get the following warning:

Warning: Attempt to present on while a presentation is in progress!

How can I display the Tweet Sheet after the dismiss animation of the Photo Library has completed?

Here is my code:

-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
image = [info objectForKey:UIImagePickerControllerOriginalImage];
[self dismissViewControllerAnimated:YES completion:nil];

[self tweet_image];
}

-(void)imagePickerControllerDidCancel:(UIImagePickerController *)picker {
    [self dismissViewControllerAnimated:YES completion:nil];
}

-(void)tweet_image {
    if ([SLComposeViewController isAvailableForServiceType:SLServiceTypeTwitter]) {

    SLComposeViewController *tweetSheet = [SLComposeViewController composeViewControllerForServiceType:SLServiceTypeTwitter];
    [tweetSheet setInitialText:[NSString stringWithFormat: @"@%@ ", USERNAME]];
    [tweetSheet addImage:image];
    [self presentViewController:tweetSheet animated:YES completion:nil];
}

else {
    UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"Sorry" message:@"You can't send a tweet right now, make sure your device has an internet connection and you have at least one Twitter account setup in iOS settings." delegate:self cancelButtonTitle:@"Dismiss" otherButtonTitles:nil];
    [alertView show];
}

}

Thanks, Dan.

Answer 1

Place your call to -tweet_image in the completion block of -dismissViewControllerAnimated:

-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
    image = [info objectForKey:UIImagePickerControllerOriginalImage];
    [self dismissViewControllerAnimated:YES completion:^ {
        [self tweet_image];
    }];
}

Answer 2

I figured out a way. I decided to make a confirmation screen with the image and then display the tweet sheet from there.