I am trying to get my dynamic content to render in a page that uses a PropertyDataCollection instead of an EPiServer property.  Initially it was just rendering the Dynamic Content control itself instead of the content.  I found the following page that explains how to get around this issue but I am encountering a runtime exception with this method.  

http://tedgustaf.com/sv/blogg/2009/9/parse-an-episerver-xhtml-property-with-dynamic-content/

I get a null reference error on the call to SetupControl() within GetRenderedXHTMLText below when rendering Dynamic Content.  Here is the relevant code...

1- As we iterate over the properties, output the content...

protected void OnItemDatabound(object sender, RepeaterItemEventArgs e)
{
    if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
    {
        PropertyXhtmlString pd = (PropertyXhtmlString)e.Item.DataItem;
        var litContent = (Literal)e.Item.FindControl("litContent");
        //For each property, attempt to get the rendered output
        litContent.Text = GetRenderedXhtmlText(pd);
    }
}

2- Try to render the content.  This method works fine for any property that doesn't have a dynamic content control in it.

public static string GetRenderedXhtmlText(PropertyXhtmlString content)
{
    // Create a Property control which will parse the XHTML value for us
    PropertyXhtmlStringControl ctrl = new PropertyXhtmlStringControl();// PropertyLongStringControl();

    // Set the PropertyData to the property we want to parse
    ctrl.PropertyData = content;

    // Initialize the Property control
    ctrl.SetupControl();//***Fails with null reference error on dynamic content***
    
    // Create a string writer...
    StringWriter sw = new StringWriter();

    // ...and an HtmlTextWriter using that string writer
    HtmlTextWriter htw = new HtmlTextWriter(sw);

    // Render the Property control to get the markup
    ctrl.RenderControl(htw);

    // Return the parsed markup
    return sw.ToString();
}

My dynamic content is a user control decorated with the DynamicContentPlugin attribute.

3- Here is my custom editor user control

public partial class NewsListCustomEditor : DynamicContentEditControl
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                txtTags.Text = Content.Properties["TagList"].Value as string;
                IList<string> tagList = txtTags.Text.Split(new string[] { "$" }, StringSplitOptions.RemoveEmptyEntries);
                txtNumItems.Text = Content.Properties["NumberOfItemsPerPage"].Value as string;
            }
        }

        public override void PrepareForSave()
        {
            Content.Properties["TagList"].Value = txtTags.Text;
            Content.Properties["NumberOfItemsPerPage"].Value = txtNumItems.Text;
            Content.Properties["DynamicContentDisplayMode"].Value = true;
        }
    }

4- Here are the relevant parts of the dynamic content user control itself

[DynamicContentPlugIn(
        DisplayName = "The Title",
        Description = "Widget to do stuff",
        ViewUrl = "~/Absolute path to this control...",
        Url = "~/Absolute path to custom editor control",
        Area = PlugInArea.DynamicContent)]
    public partial class NewsList : UserControlBase
    {
... body of control, do stuff, get data etc.

public Control GetControl(PageBase hostPage)
        {
            //try
            //{
                if(hostPage==null)
                    hostPage=(HttpContext.Current.Handler as PageBase); 
                //Return dynamic content controls
                return (NewsList)hostPage.LoadControl("~/Templates/Responsive/Controls/NewsList.ascx");
            //}
        }

        #endregion
        

        private static string GetPropertyString(string PropertyName, PageData pageData)
        {
            return pageData[PropertyName] as string ?? String.Empty;
        }

Well, sorry for the long post, but would like to get this working and have no idea what is missing from my dynamic content control that makes SetupControl fail...

Any ideas?