Modifying UINavigation controller programatically in Xcode5 - objective-c

Question

I have a programmatically generated UINavigationController applied to each of my ViewControllers but this UINavigationController is blank. I need to add some text, an image (if possible) and two buttons.
I have managed to do something similar with a very basic app that only has one ViewController and UINavigationController created in the normal manner but do not know what to do in regards to a programmatically generated one.
I am using storyboards in XCode5/iOS7.
Here is the code that generates the UINavigationController and launches the first ViewController:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:#"Main" bundle: nil];
MainViewController* mainVC = [mainStoryboard instantiateInitialViewController];
UINavigationController *navVC = [[UINavigationController alloc] initWithRootViewController:mainVC];
[self.window setRootViewController:navVC];
[_window makeKeyAndVisible];
return YES;
}
I have tried things that I thought would be obvious like:
navVC.navigationBar.backgroundColor = [UIColor redColor];
To change the colour or:
[navVC setTitle:#"Test title"];
But nothing changes, the only way I could get the title to change was to change the title of mainVC
[mainVC setTitle:#"Test title"];
Changing the title in the MainViewController.m file itself does nothing.
So how do I modify the UINavigationController (navVC)?
Thanks,

Answer 1

You should be able to set an image to your navigation bar in this way:
UINavigationBar *navBar = navVC.navigationBar;
UIImage *image = [UIImage imageNamed:#"YourNavBarImg.png"];
[navBar setBackgroundImage:image];
and this to change the nav bar tint color:
[navVC.navigationBar setTranslucent:NO];
[navVC.navigationBar setBarTintColor:[UIColor redColor]];
about buttons (UIBarButtonItem) into nav bar:
// where "self" is your current viewcontroller
self.navigationItem.rightBarButtonItems = [NSArray arrayWithObjects:button1,button2, nil];