Restore and preserve UIViewController pushed from UINavigationController, no storyboard

Question

I try to restore a simple UIViewController that I pushed from my initial view controller. The first one is preserved, but the second one just disappear when relaunched. I don't use storyboard. I implement the protocol in every view controller and add the restorationIdentifier and restorationClass to each one of them.

The second viewController inherit from a third viewController and is initialized from a xib file. I'm not sure if I need to implement the UIViewControllerRestoration to this third since I don't use it directly.

My code looks like typically like this:

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
        self.restorationIdentifier = @"EditNotificationViewController";
        self.restorationClass = [self class];
    }
    return self;
}

-(void)encodeRestorableStateWithCoder:(NSCoder *)coder
{

}
-(void)decodeRestorableStateWithCoder:(NSCoder *)coder
{

}

+(UIViewController *)viewControllerWithRestorationIdentifierPath:(NSArray *)identifierComponents coder:(NSCoder *)coder
{
    EditNotificationViewController* envc = [[EditNotificationViewController alloc] initWithNibName:@"SearchFormViewController" bundle:nil];
    return envc;
}

Should perhaps the navigationController be subclassed so it too can inherit from UIViewControllerRestoration?

UPDATE: Ok, it seems like pushing from UIViewController to UIViewController works. But pushing from UIViewController to UITableViewController and vice versa, don't work. The app crashes if the tableview implements the UIViewControllerRestoration protocol. If I don't implement the protocol, UIViewControllers pushed from the tableView is not preserved.

How should one treat UITableViewControllers to preserve them without a crash?

UPDATE: No crashing no more.. It was due to a memory bug specific for my app. But the tableView is still not preserved, neither the pushed viewController.

UPDATE: The reason my tableview did not restore properly was because I deleted my datasource in the background.. But I still have a problem with modal viewController not showing up when I try to push it on another navigationController than self.navigationController. I set the restoration identifier to this modal navigationController, but the view does not show up.

Answer 1

The modal transition needs to be backed by a UINavigationController which has a restorationIdentifier and either a restoration class or a corresponding implementation in the app delegates method viewControllerWithRestorationIdentifierPath. That solved the last piece of the problem.