Question

consider the following scenario: I have a storyboard-based app. I add a ViewController object to the storyboard, add the class files for this ViewController into the project and specify the name of the new class in the IB identity inspector. Now how am I going to refer to this ViewController programmatically from the AppDelegate? I’ve made a variable with the relevant class and turned it into an IBOutlet property, but I don’t see any way of being able to refer to the new ViewController in code – any attempt to ctrl-drag a connection doesn’t work.

i.e. within the AppDelegate I can get to the base ViewController like this

(MyViewController*) self.window.rootViewController

but how about any other ViewController contained within the storyboard?

Answer 1

Have a look at the documentation for -[UIStoryboard instantiateViewControllerWithIdentifier:]. This allows you to instantiate a view controller from your storyboard using the identifier that you set in the IB Attributes Inspector:

EDITED to add example code:

UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:@"MainStoryboard"
                                                         bundle: nil];

MyViewController *controller = (MyViewController*)[mainStoryboard 
                    instantiateViewControllerWithIdentifier: @"<Controller ID>"];