NavigationController is showing another view controller instead of pushing viewcontroller

Question

I have main ViewController which is named ViewController(if i run my project it runs firstly). If i push my DetailViewController, it is showing my ViewController view.

Here is my part of code:

AppDelegate.m

ViewController *viewController = [[ViewController alloc] initWithNibName:Nil bundle:nil];
    self.navigationController = [[UINavigationController alloc] initWithRootViewController:viewController];

    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    self.window.rootViewController = self.navigationController;
    [self.window makeKeyAndVisible];

Viewcontroller.m

DetailViewController *detailVC = [[DetailViewController alloc] initWithNibName:nil bundle:NULL];
    [self.navigationController pushViewController:detailVC animated:YES];

Answer 1

In your Button's Action, implement this

DetailViewController *detailVC = [[DetailViewController alloc] initWithNibName:@"DetailViewController" bundle:nil];
[self.navigationController pushViewController:detailVC animated:YES];

You are not initializing with its nib file

Answer 2

Check following code

DetailViewController *detailVC = [[DetailViewController alloc] init];
[self.navigationController pushViewController:detailVC animated:YES];