1.去掉UITabBarController背景色自带的蒙版

        [tabbarController.tabBarsetBackgroundColor:[UIColorwhiteColor]];

        [tabbarController.tabBarsetBackgroundImage:[UIImagenew]];

并且注意

     [UITabBar appearance].barStyle = UIBarStyleDefault;

可以看看Black的效果

2.设置UITabBarController上UITabbarItem的字体颜色及选中态颜色

        NSMutableDictionary *attr3=[NSMutableDictionary dictionary];

        attr3[NSForegroundColorAttributeName]=[UIColor blackColor];

        attr3[NSFontAttributeName]=[UIFontsystemFontOfSize:CTabbarFontSize];

        [[UITabBarItem appearance]setTitleTextAttributes:attr3 forState:UIControlStateNormal];

        NSMutableDictionary *attr4=[NSMutableDictionary dictionary];

        attr4[NSForegroundColorAttributeName]=[UIColor redColor];

        attr4[NSFontAttributeName]=[UIFontsystemFontOfSize:CTabbarFontSize];

        [[UITabBarItem appearance]setTitleTextAttributes:attr4 forState:UIControlStateSelected];

3.关于UITabbar一开始颜色正确，进入页面再出来后颜色错误的问题，是因为退出后按钮显示的是你设置的setTintColorColor

所以要增加tintcolor与上面的arrt4一致。

  [tabbarController.tabBarsetTintColor:[UIColor  redColor]];