返回present的根

//返回四大tab页面
+ (void)gobackToTabarController
{
    UINavigationController* selectedTabNavController = (UINavigationController *)[QZoneUIAppDelegate shareInstance].qqTabbarController.selectedViewController;
    UIViewController* pCurController = (UIViewController*)selectedTabNavController.visibleViewController;

    UIViewController* rootViewController = pCurController;
    for (; rootViewController.presentingViewController; ) {
        rootViewController = rootViewController.presentingViewController;
    }

    [rootViewController dismissViewControllerAnimated:NO completion:nil];
    [rootViewController.navigationController popToRootViewControllerAnimated:NO];
}

- (void)switchToTab:(int)tabIndex
{
    //通用处理，切换到好友动态的时候，将我的空间poptoroot。
    if (tabIndex == 0) {
        [_spaceStatusController.navigationController popToRootViewControllerAnimated:NO];
        [_passiveFeedController.navigationController popToRootViewControllerAnimated:NO];
        [_homePageController.navigationController popToRootViewControllerAnimated:NO];
        [_gameViewController.navigationController popToRootViewControllerAnimated:NO];
    }

    if (_qqTabbarController.selectedIndex != tabIndex)
    {
        QZLOG_INFO(@"loading图流程 - 切换tab");
        [_qqTabbarController setSelectedIndex:tabIndex];
    }
    else
    {
        QZLOG_INFO(@"switchTo empty tab");
    }
}