Question

I’ve got a ViewController, that has a UIButton which performs the following:

- (IBAction)buttonClicked:(id)sender 
{
    NSLog(@"Button clicked, lets move to next controller to do stuff");
    [self performSegueWithIdentifier:@"toNextController" sender:nil];
}

This just moves onto my next ViewController, nothing amazing so far.

In the second ViewController, I will do some of my application logic, then return.

- (IBAction)backButtonPressed:(id)sender 
{
    NSLog(@"Back button clicked, lets just drop out of here...");
    [self dismissModalViewControllerAnimated:YES];
}

- (IBAction)saveButtonPressed:(id)sender 
{
    NSLog(@"save button clicked, lets send some data back");

    [self performSegueWithIdentifier:@"backToMain" sender:nil];
}

-(void) prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{    
    if ([segue.identifier isEqualToString:@"backToMain"])
    {
        NSLog(@"Preparing segue for backToMain");

        // Obtain handles on the current and destination controllers
        MainController * startingViewController;
        SecondController * destinationController;

        startingViewController = (MainController * ) segue.sourceViewController;
        destinationController = (SecondController * ) segue.destinationViewController;

        // set data on the main controller
        startingViewController.myString = @"SomeDummyString";
    }
}

What I have tried to do so far, is to create a second segue that links back to the main controller, and before performing the segue, grab a handle on it and set data. I’m not sure if that is the best way of navigating back or not.

Question:

Is it possible, to return data when doing a [self dismissModalViewControllerAnimated:YES];, or do you need to implement a segue for the return journey?

Answer 1

Check this out: 10841897

It describes using a delegate and protocol to send the information back and forth. It can be slightly changed to fit your needs, just create a savedWithData: method that sends a dictionary or whatever data you want back to the first view controller rather than just the generic done which is described in the link.