系统的Tabbar的默认选中图标显示蓝色，实际图片为橙色

修改tabbar默认蓝色：

  UIImage *img = [UIImage imageNamed:@"tabbar_message_hl"];
    img =  [img imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];
    [self.tabBarItem setFinishedSelectedImage:img
                  withFinishedUnselectedImage:[UIImage imageNamed:@"tabbar_message"]];