iOS 刷新tabbar消息角标

在通知里面刷新消息数量角标

1.带导航栏，msgVc为消息页面

  self.msgVc.navigationController.tabBarItem.badgeValue = [NSString stringWithFormat:@"%ld", (long)bageCount];

2.不带导航栏

 self.msgVc.tabBarItem.badgeValue = [NSString stringWithFormat:@"%ld", (long)bageCount];