iOS导航栏的一些设置

    //显示隐藏的导航栏

    self.navigationController.navigationBarHidden = NO;

    //导航栏背景颜色设置

    [self.navigationController.navigationBar setBarTintColor:[Scale colorWithHexString:@"#055fd7"]];

    self.navigationItem.title = @"公告详情";

    //导航栏title字体颜色设置

    [self.navigationController.navigationBar setTitleTextAttributes:@{NSFontAttributeName:[UIFont systemFontOfSize:17],NSForegroundColorAttributeName:[UIColor whiteColor]}];

    //导航栏leftBarButtonItem，以及图片颜色

    UIBarButtonItem *myButton = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:@"navi_arrow"] style:UIBarButtonItemStylePlain target:self action:@selector(backAction)];

    self.navigationItem.leftBarButtonItem = myButton;

    self.navigationItem.leftBarButtonItem.tintColor = [UIColor whiteColor];