判断当前控制器是否是pop回来的

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
//    if (self.isMovingToParentViewController == NO && !self.presentedViewController)
//    {
//        [self getInfos];
//    }
    UIViewController *fromViewController = [[[self navigationController] transitionCoordinator] viewControllerForKey:UITransitionContextFromViewControllerKey];
    
    if (![[self.navigationController viewControllers] containsObject:fromViewController] && !self.presentedViewController)
    {//Something is being popped and we are being revealed
        [self getInfos];
    }
}