在自定义的UINavigationController中设置背景图片

//这个方法中设置

+ (void)initialize

{

UINavigationBar *bar = [UINavigationBar appearance];

[bar setBackgroundImage:[UIImage imageNamed:@"bg_navigationBar_normal"] forBarMetrics:UIBarMetricsDefault];

}

- (void)viewDidLoad {

[super viewDidLoad];

// Do any additional setup after loading the view.

}

- (void)didReceiveMemoryWarning {

[super didReceiveMemoryWarning];

// Dispose of any resources that can be recreated.

}