Get ViewController from Storyboard

Question

I have two ViewControllers, which aren`t (directly) connected with a Segue. But I want to change a String in the second VC, which i get in the first one. My try was:

    #import "secondViewController.h"

    @interface firstViewController ()
    @property NSString* originalString;
    @end

    @implementation firstViewController

    -(void)viewDidDisappear:(BOOL)animated{
        [super viewDidDisappear:animated];
        secondViewController* svc = [secondViewController new];
        svc.anotherString = self.originalString;    
    }

But it dosent work, because I've only created a instance of the second VC, so the value was not saved. Also I can`t use the Storyboard ID, because I use Xcode 5.

I have a menuVC from which you can get to the firstVC and the secondVC. And from the firstVC I can go back (with the navigationbackbarbutton) to the menu. so: menu->firstVC->menu. menu->secondVC->...->menu

My try with StoryboardID:

    -(void)viewDidDisappear:(BOOL)animated{
        [super viewDidDisappear:animated];

        secondViewController* svc =[[UIStoryboard storyboardWithName:@"MainStoryboard_iPhone" bundle:nil] instantiateViewControllerWithIdentifier:@"secondVCSrorybradID"];

        svc.anotherString = self.originalString;    
    }

Solution 1

You should pass your data successively through your UIViewControllers navigation. If, for example, you have a navigation like FirstVC > SecondVC > ThirdVC :

In your FirstVC.m, use :

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {

    ((SecondVCClass*) segue.destinationViewController).secondVCString = _firstVCString;
}

With secondVCString being a @property in your second ViewController.

In your SecondVC.m, use :

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {

    ((ThirdVCClass*) segue.destinationViewController).thirdVCString = _secondVCString;
}

With of course thirdVCString being a @property in your third ViewController.

---

Edit:

As you updated your question, here is what I suggest :

• In your MenuVC, add this :

  @property (nonatomic, weak) NSString *importantString;
  

• In your FirstVC and SecondVC, add this :

  @property (nonatomic, weak) MenuVCClass *menu;
  

• When you push to FirstVC or SecondVC, use prepareForSegue to set the destination's view controller menu property to your menu :

  -(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
  
      if ([segue.identifier isEqualToString:@"FirstSegue"])
          ((FirstVC*) segue.destinationViewController).menu = self;
      else if ([segue.identifier isEqualToString:@"SecondSegue"])
          ((SecondVC*) segue.destinationViewController).menu = self;
  }
  

• In FirstVC or SecondVC, you can change the NSString value from your menu using _menu.importantString = @"";

Solution 2

You should never use new to create a view controller.

If you're using storyboards but not using segues, you can still create a view controller from the storyboard and invoke it.

Use the method instantiateViewControllerWithIdentifier: to create an instance of the target view controller. The set the properties you want to set, and finally make a call to display it (present it modally, push it onto the navigation stack, or whatever is appropriate for your program.)

Comments

[Sam]

thanks, but my first and my sec on VC goes both from another VC so when I get back to my menu the method "prepareForSegue" won't be called.

[rdurand]

Can you edit your question with your app's structure ? Something like FirstVC -- SecondVC -- etc.

[Duncan C]

Can't use a storyboard ID you mean? Why? You said "because I use Xcode 5", which does not make any sense.

[Sam]

but i haven't any storryboard ID, really... I've only Title

[Duncan C]

Ok, but you can (and should) assign a storyboard ID to any scene in your s storyboard. This is supported from Xcode 4.0 to the current version, 5.0.2

[Duncan C]

Dude, you need to write sentences that other people can understand if you actually want help. "It wouldn't be saved" is not one of those sentences.

[Sam]

YES it works!! thanks :D Not exactly like you but it was your main idea with the menuVC thanks soooooooooo much!! §> U