How do I implement a UINavigationController in this case? - objective-c

Question

current version of my project :
I have 5 different UIViewControllers in my app. I've set my
FirstViewController to be the Initial View Controller using the
Attributes Inspector. I move back and forth from one ViewController to
another by using buttons to which I assign modal segues, from one
ViewController to another, using the StoryBoard
What I want to change:
I want to keep the navigation buttons obviously, delete the modal segues and use
a UINavigationController instead. If I understand the concept
correctly, when using a UINavigationController I need to go into each
UIButton-IBAction and at the very end of the method I have to push the next
ViewController I want to move to, onto my NavigationController (do I also
have to pop the current one first?). However, I can't figure out how
to implement all that correctly.
What I've done so far:
I removed all modal segues from the storyboard and kept the navigation buttons along with their corresponding IBActions
I unchecked the box in the Attributes Inspector that was making my FirstViewController the initial View Controller of my app
I went into my AppDelegate.m and tried to create the Navigation Controller there and make my FirstViewController be the RootViewController
MyAppDelegate.m
-(BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
UIViewController *myFirstViewController = [[FirstViewController alloc] init];
UINavigationController *myNavigationController = [[UINavigationController alloc] initWithRootViewController:myFirstViewController];
[myNavigationController pushViewController:myFirstViewController animated:YES];
// Override point for customization after application launch.
return YES;
}
I then tried to test if the above was working by going into the IBAction of a
navigation button on my FirstViewController and implemented the
following in order to move to my SecondViewController when the
button is pressed :
FirstViewController.m
- (IBAction)goRightButton:(UIButton *)sender
{
// some code drawing the ButtonIsPressed UIImageView on the current View Controller
UIViewController *mySecondViewController = [[SecondViewController alloc] init];
[self.navigationController pushViewController:mySecondViewController animated:YES];
}
but nothing happens. What am I doing wrong ?

Answer 1

You are not linking your XIB file. Please add your navigation controller as
UIViewController *myFirstViewController = [[FirstViewController alloc] initWithNibName:#"FirstViewController" bundle:nil];
navigationController = [[UINavigationController alloc] initWithRootViewController:myFirstViewController];
Use following code to move from one view to another
UIViewController *mySecondViewController = [[SecondViewController alloc] initWithNibName:#"SecondViewController" bundle:nil];
[self.navigationController pushViewController:mySecondViewController animated:YES];

Answer 2

If you are using a storyboard, you should just drag in the navigation controller there and hook it up to your app delegates. As long as it is the main storyboard, and you have identified a view controller to load first, you do not need to load any views in your app delegate.
In order to push a view programmatically that's in a storyboard, you need to do something like the following:
//bundle can be nil if in main bundle, which is default
UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:#"MainStoryboard" bundle:nil];
MyCustomViewController *customVC = (MyCustomViewController *)[mainStoryboard instantiateViewControllerWithIdentifier:#"customVC"];
//standard way
[self.navigationController pushViewController:customVC animated:YES];
//custom animation
[UIView transitionWithView:self.navigationController.view duration:0.5 options:UIViewAnimationOptionTransitionCurlUp animations:^{
[self.navigationController pushViewController:customVC animated:NO];
} completion:nil];
You identify the view controller with the identifier you add in the storyboard editor. Below are some screenshots to help show what I mean.