CollectionViewCells do not display any data

Question

I've used CollectionViews in my project in another area of my project successfully with no issues, but this one simply won't display the data in the cell no matter what I do. I can see the cell border, it is the correct width and height, and when I step through the code I see the data get assigned to the label in the cell. I see the correct number of cells for the list of strings that's in the source, just get nothing displayed. I cannot figure out why. Anyone see any problems with my code? This should be pretty simple, and I've been at it for 3 days now with no results.

My Cell Code:

public partial class PhoneNumberCell : UICollectionViewCell
{
    public static readonly NSString Key = new NSString("PhoneNumberCell");

    UILabel lblPhoneNumberInfo = new UILabel();

    [Export("initWithFrame:")]
    public PhoneNumberCell(CGRect frame) : base(frame)
    {
        // I set the frame and text color because in other instances 
        // of data not showing up, that's proved to be the issue.
        // Apparently not here, I remove this code and still no text in the cell.
        lblPhoneNumberInfo.Frame = new CGRect(0,0,ContentView.Frame.Width, 26f);
        lblPhoneNumberInfo.TextColor = UIColor.Black;
        // I do see the border around the cell though.
        ContentView.Layer.BorderColor = UIColor.LightGray.CGColor;
        ContentView.Layer.BorderWidth = 2.0f;
        ContentView.BackgroundColor = UIColor.White;
        ContentView.Transform = CGAffineTransform.MakeScale(0.8f, 0.8f);
    }

    public void SetData(string pPhoneNumberInfo)
    {
        lblPhoneNumberInfo.Text = pPhoneNumberInfo;
    }

    protected PhoneNumberCell(IntPtr handle) : base(handle)
    {
        // Note: this .ctor should not contain any initialization logic.
    }
}

The XIB:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<document type="com.apple.InterfaceBuilder3.CocoaTouch.XIB" version="3.0" toolsVersion="6211" systemVersion="14A298i" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES">
  <dependencies>
    <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="7026.1" />
  </dependencies>
  <objects>
    <placeholder placeholderIdentifier="IBFilesOwner" id="-1" userLabel="File's Owner" />
    <placeholder placeholderIdentifier="IBFirstResponder" id="-2" customClass="UIResponder" />
    <collectionViewCell opaque="NO" clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="center" customClass="PhoneNumberCell" id="cZE-iV-UFb">
      <rect key="frame" x="0.0" y="0.0" width="50" height="50" />
      <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMinY="YES" />
      <view key="contentView" opaque="NO" clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="center">
        <rect key="frame" x="0.0" y="0.0" width="50" height="50" />
        <autoresizingMask key="autoresizingMask" />
        <color key="backgroundColor" white="0.0" alpha="0.0" colorSpace="calibratedWhite" />
      </view>
    </collectionViewCell>
  </objects>
</document>

The Source:

public class PhoneNumberSource : UICollectionViewSource
{
    public IList<string> PhoneNumbers;
    public override nint NumberOfSections(UICollectionView collectionView)
    {
        return 1;
    }
    public override nint GetItemsCount(UICollectionView collectionView, nint section)
    {
        return PhoneNumbers.Count;
    }

    public PhoneNumberSource(IList<string> pPhoneNumbers)
    {
        PhoneNumbers = pPhoneNumbers;
    }
    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;
    }
}

My CollectionView layout:

    PhoneNumberList.CollectionViewLayout = new UICollectionViewFlowLayout()
    {
        ItemSize = new CGSize((float)UIScreen.MainScreen.Bounds.Size.Width, 26f),
        HeaderReferenceSize = new CGSize(25, 25),
        SectionInset = new UIEdgeInsets(0, 0, 0, 0),
        ScrollDirection = UICollectionViewScrollDirection.Vertical,
        MinimumInteritemSpacing = 0, // minimum spacing between cells
        MinimumLineSpacing = 0,
    };

Answer 1

The solution is that you need to AddSubview for the ContentView like below:

ContentView.AddSubview(lblPhoneNumberInfo);