/* 配置navigation bar外观开始 */

    self.navigationBar.translucent = YES;

    self.navigationBar.titleTextAttributes =

    [NSDictionary dictionaryWithObject:[UIColor whiteColor]

                                forKey:NSForegroundColorAttributeName];

    self.navigationBar.tintColor = [UIColor whiteColor];    // 文字颜色

    self.navigationBar.barTintColor =     // navigation bar颜色

    [[UIColor alloc] initWithRed:17/255.0 green:169/255.0 blue:172/255.0 alpha:0.5];

    /* 配置navigation bar外观结束 */