Any NSWindowRestoration examples?

There is one little code snipet:

+ (void)restoreWindowWithIdentifier:(NSString *)identifier state:(NSCoder *)state completionHandler:(void (^)(NSWindow *, NSError *))completionHandler
{
   // Get the window from the window controller,
   // which is stored as an outlet by the delegate.
   // Both the app delegate and window controller are
   // created when the main nib file is loaded.
   MyAppDelegate* appDelegate = (MyAppDelegate*)[[NSApplication sharedApplication] delegate];
   NSWindow* mainWindow = [appDelegate.windowController window];

   // Pass the window to the provided completion handler.
   completionHandler(mainWindow, nil);
}

Found here.

Hopefully this will help you.

Edit:

Be sure you are implementing the protocol in your application class, remember you have to add it in your m file.

@interface MyClass : FatherClass <NSWindowRestoration>

**I'm not 100% of the name of the protocol so that last line could be wrong, sorry I'm in a rush right now, it's either that or NSWindowRestorationDelegate.