Csharp 在RootViewController上访问UILabel

再一次，解决方案被证明是相当简单的.在我的UICollectionViewSource中，我声明了一个变量private MyViewController MyParentController { get; set; }.当我初始化传入父视图控制器的UICollectionViewSource时，我的`PhoneNumberSource:code:

public class PhoneNumberSource : UICollectionViewSource
{
    public IList<string> PhoneNumbers;
    private MyViewController MyParentController { get; set; }

    public override nint NumberOfSections(UICollectionView collectionView)
    {
        return 1;
    }
    public override nint GetItemsCount(UICollectionView collectionView, nint section)
    {
        return PhoneNumbers.Count;
    }

    public PhoneNumberSource(MyViewController  pMyParentController, IList<string> pPhoneNumbers)
    {
        PhoneNumbers = pPhoneNumbers;
        MyParentController = pMyParentController;
    }
    public override UICollectionViewCell GetCell(UICollectionView collectionView, NSIndexPath indexPath)
    {
        var phoneNumberCell = (PhoneNumberCell)collectionView.DequeueReusableCell(PhoneNumberCell.Key, indexPath);
        string phoneinfo = PhoneNumbers[indexPath.Row];
        phoneNumberCell.SetData(phoneinfo);
        return phoneNumberCell;
    }
    public override void ItemSelected(UICollectionView collectionView, NSIndexPath indexPath)
    {
        PhoneNumberCell thecell = collectionView.CellForItem(indexPath) as PhoneNumberCell;
        if (Utils.PhoneNumbersCheck[indexPath.Row][1] == "1")
        {
            Utils.PhoneNumbersCheck[indexPath.Row][1] = "0";
        }
        else
        {
            Utils.PhoneNumbersCheck[indexPath.Row][1] = "1";
        }
        thecell.ToggleCheckBox();

        MyParentController.Updatelabel();
    }
}

在视图控制器中，我按如下方式初始化CollectionViewSouce:

PhoneNumberList.Source = new PhoneNumberSource(this, Utils.PhoneNumbers);

标签每次都会更新.而且似乎我可以访问父视图控制器的所有方法和属性.