隐藏底部导航栏tabbar

在有tabbarcontroller时，A界面push到B界面想隐藏底部tabbar，从B界面返回A后再显示tabbar。那么在控制器A中可以设置

-(void)clickTheSettingBtn{
    ControllerB *vcB = [[ControllerB alloc]init];
    //在跳转之前设置为YES
    self.hidesBottomBarWhenPushed = YES;
    [self.navigationController pushViewController:vcB animated:YES];
    //在跳转之后再设置为NO
    self.hidesBottomBarWhenPushed = NO;
}