UINavigationController custom navigation bar

MyAppDelegate.m

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    // Override point for customization after application launch.

    // Create a new window and assign directly to provided iVar
    _window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    
    // Implementation of new init method
    MyCustomNavigationBar *navigationBar = [[MyCustomNavigationBar alloc] initWithFrame:CGRectZero];
    UINavigationController *navigationController = [[UINavigationController alloc] initWithCustomNavigationBar:navigationBar];
    [navigationBar release];
    
    [self.window setRootViewController:navigationController];
    [navigationController release];

    [self.window makeKeyAndVisible];
    return YES;
}

UINavigationController-CustomNavigationBar.h

#import <UIKit/UIKit.h>

@interface UINavigationController (MTCustomNavigationBar)

- (id)initWithCustomNavigationBar:(UINavigationBar *)navigationBar;

@end

UINavigationController-CustomNavigationBar.m

#import "UINavigationController-MTCustomNavigationBar.h"
#import <objc/runtime.h>

@implementation UINavigationController (MTCustomNavigationBar)

- (id)initWithCustomNavigationBar:(UINavigationBar *)navigationBar
{
    self = [self initWithNibName:nil bundle:nil];
    
    if (self)
    {
        // Init
        [self setValue:navigationBar forKey:@"navigationBar"];
    }
    
    return self;
}

@end

Does not work

This method is not ARC compatible. If you are using ARC you can simply replace the navigation bar using:
[navigationController setValue:navigationBar forKey:@"navigationBar"].

Hi Nitewriter:

I test your code on ios5.1, the custom navigation bar appears, but the back button on the bar doesn't work, it doesn't call popViewControllerAnimated method when tap back button, however the back button will disappear...it is weird.

best regards

iOS 5.x introduced changes to the UINavigationBar that cause issues when using this method of replacement. You should use the setValue:forKey: replacement I mentioned to ihmunro.

thanks for your feedback