Upvote:4

Aprove answer 
 if([[UINavigationBar class] respondsToSelector:@selector(appearance)]) //iOS >=5.0
    {
        UIImage * navBarImage = [UIImage imageNamed:@"image.png"] ;
        [[UINavigationBar appearance]setBackgroundImage: navBarImage  forBarMetrics:UIBarMetricsDefault];
}

Upvote:0 

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
}

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