Define EditorTemplate for child collection in viewmodel

Question

I've got a model which contains a List of QuestionEditModel for which I want to use an EditorFor.

Normally, I would just call EditorFor on the collection and MVC will do the rest. However, I need the individual QuestionEditModel to use different EditorTemplates depending on the value of a field within the object.

I would've thought that the method for doing this would be something like

<%: Html.EditorFor(model=>model.Questions), [fieldname from individual question] %>

but I cannot figure out how to tell it to look at the Question which is currently selected and use the EntryType field from the question to determine which EditorTemplate to use.

So I tried this

            <% foreach (Reviewer.Models.QuestionEditModel qem in Model.Questions)
           {
               Html.EditorFor(q=>qem, qem.EntryType, null);
           } %>

but this doesn't render anything on to the page. The odd thing is that if I set a breakpoint and run over the code, this does call the correct EditorTemplate, the correct model data is passed in and there are no exceptions, but it just doesn't render anything.

Is there some additional work I need to do in this scenario to get the rendered EditorTemplate back in to my page?

EDIT:

Full code of the Edit View.

<% using (Html.BeginForm()) {%>
    <%: Html.ValidationSummary(true) %>

    <%: Html.HiddenFor(model=>model.AcadPeriod) %>
    <%: Html.HiddenFor(model=>model.ReviewID) %>
    <%: Html.HiddenFor(model=>model.ReviewName) %>
    <%: Html.HiddenFor(model=>model.CategoryID) %>
    <%: Html.HiddenFor(model=>model.CategoryName) %>
    <%-- Categories not getting returned in model for some reason. Use EditorFor or DisplayFor instead of loop? --%>
    <%: Html.HiddenFor(model=>model.Categories) %>
    <%: Html.HiddenFor(model=>model.ClassificationID) %>
    <%: Html.HiddenFor(model=>model.ClassificationName) %>

    <div style="width:100%">

    <div style="float:left">
        <ul style="list-style-type:none">
            <% for (int i = 0; i < Model.Categories.Count(); i++)
               { %>
            <li style="background-color:Gray; border: 1px solid black; padding: 3px 3px 3px 3px; margin-bottom: 2px">
            <%: Html.ActionLink(Model.Categories[i].name, "Edit", new { AcadPeriod = Model.AcadPeriod, ClassificationID=Model.ClassificationID, ReviewID=Model.ReviewID, CategoryID=Model.Categories[i].category_id })%>
            </li>
            <% }%>
        </ul>
    </div>

    </div>
                <% foreach (Reviewer.Models.QuestionEditModel qem in Model.Questions) { %> 
                     <%: Html.EditorFor(q=>qem, qem.EntryType,null); %> 
                <% } %> 

        <p>
            <input type="submit" value="Save" />
        </p>

<% } %>

EDIT 2:

Complete View, Controller, and Template code as requested.

<%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<Reviewer.Models.ReviewEditModel>" %>

<asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
Edit
</asp:Content>

<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">

<h1><%: Model.AcadPeriod %> &gt; <%: Model.ClassificationName %> &gt; <%: Model.ReviewName %></h1>

<% using (Html.BeginForm()) {%>
    <%: Html.ValidationSummary(true) %>

    <%: Html.HiddenFor(model=>model.AcadPeriod) %>
    <%: Html.HiddenFor(model=>model.ReviewID) %>
    <%: Html.HiddenFor(model=>model.ReviewName) %>
    <%: Html.HiddenFor(model=>model.CategoryID) %>
    <%: Html.HiddenFor(model=>model.CategoryName) %>
    <%-- Categories not getting returned in model for some reason. Use EditorFor or DisplayFor instead of loop? --%>
    <%: Html.HiddenFor(model=>model.Categories) %>
    <%: Html.HiddenFor(model=>model.Questions) %>
    <%: Html.HiddenFor(model=>model.ClassificationID) %>
    <%: Html.HiddenFor(model=>model.ClassificationName) %>

    <div style="width:100%">

    <div style="float:left;width: 15%">
        <ul style="list-style-type:none">
            <% for (int i = 0; i < Model.Categories.Count(); i++)
               { %>
            <li style="background-color:Gray; border: 1px solid black; padding: 3px 3px 3px 3px; margin-bottom: 2px">
            <%: Html.ActionLink(Model.Categories[i].name, "Edit", new { AcadPeriod = Model.AcadPeriod, ClassificationID=Model.ClassificationID, ReviewID=Model.ReviewID, CategoryID=Model.Categories[i].category_id })%>
            </li>
            <% }%>
        </ul>
    </div>

    <div style="float:left; width: 80%; margin-left: 5px">

<% foreach (Reviewer.Models.QuestionEditModel qem in Model.Questions) { %> 
 <%: Html.EditorFor(q=>qem, qem.EntryType,null) %> 
<% } %> 

    </div>
    </div>
    <div style="clear:both" />
        <p>
            <input type="submit" value="Save" />
        </p>

<% } %>

<div>
    <%: Html.ActionLink("Back to List", "Index") %>
</div>

</asp:Content>

Editor Template:

<%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<Reviewer.Models.QuestionEditModel>" %>

<div style="width:100%; border: 1px solid black">
 <div style="width: 100%; border: 1px solid black"><h2><%: Model.QuestionName %></h2></div>
<div style="width:25%; display:inline; border: 1px solid black; float:left">
    <%: Model.QuestionText %>
</div>
<div style="width:70%; border: 1px solid black; float:left">
    <%: Html.TextAreaFor(model=>model.Answer) %>
    <%:Html.ValidationMessageFor(model=>model.Answer) %>
</div>

 <div style="clear:both" />
</div>

    <fieldset>
        <legend>TEXT</legend>

        <div class="editor-label">
            <%: Html.LabelFor(model => model.QuestionID) %>
        </div>
        <div class="editor-field">
            <%: Html.TextBoxFor(model => model.QuestionID) %>
            <%: Html.ValidationMessageFor(model => model.QuestionID) %>
        </div>

        <div class="editor-label">
            <%: Html.LabelFor(model => model.QuestionName) %>
        </div>
        <div class="editor-field">
            <%: Html.TextBoxFor(model => model.QuestionName) %>
            <%: Html.ValidationMessageFor(model => model.QuestionName) %>
        </div>

        <div class="editor-label">
            <%: Html.LabelFor(model => model.QuestionText) %>
        </div>
        <div class="editor-field">
            <%: Html.TextBoxFor(model => model.QuestionText) %>
            <%: Html.ValidationMessageFor(model => model.QuestionText) %>
        </div>

        <div class="editor-label">
            <%: Html.LabelFor(model => model.DefaultText) %>
        </div>
        <div class="editor-field">
            <%: Html.TextBoxFor(model => model.DefaultText) %>
            <%: Html.ValidationMessageFor(model => model.DefaultText) %>
        </div>

        <div class="editor-label">
            <%: Html.LabelFor(model => model.EntryType) %>
        </div>
        <div class="editor-field">
            <%: Html.TextBoxFor(model => model.EntryType) %>
            <%: Html.ValidationMessageFor(model => model.EntryType) %>
        </div>

        <div class="editor-label">
            <%: Html.LabelFor(model => model.HelpText) %>
        </div>
        <div class="editor-field">
            <%: Html.TextBoxFor(model => model.HelpText) %>
            <%: Html.ValidationMessageFor(model => model.HelpText) %>
        </div>

        <div class="editor-label">
            <%: Html.LabelFor(model => model.Answer) %>
        </div>
        <div class="editor-field">
            <%: Html.TextBoxFor(model => model.Answer) %>
            <%: Html.ValidationMessageFor(model => model.Answer) %>
        </div>

        <div class="editor-label">
            <%: Html.LabelFor(model => model.OptionValue) %>
        </div>
        <div class="editor-field">
            <%: Html.TextBoxFor(model => model.OptionValue) %>
            <%: Html.ValidationMessageFor(model => model.OptionValue) %>
        </div>

        <div class="editor-label">
            <%: Html.LabelFor(model => model.completedBy) %>
        </div>
        <div class="editor-field">
            <%: Html.TextBoxFor(model => model.completedBy) %>
            <%: Html.ValidationMessageFor(model => model.completedBy) %>
        </div>

        Option Required: <%:Html.TextBoxFor(model=>model.OptionRequired) %>
        Answer Required: <%: Html.TextBoxFor(model=>Model.AnswerRequired) %>

    </fieldset>

Edit(GET) Action:

        public ActionResult Edit(string AcadPeriod, string ClassificationID, string ReviewID, int CategoryID)
    {
        Reviewer.Models.ReviewEditModel dset1 = rr.GetReviewEditModel(AcadPeriod, ReviewID, CategoryID.ToString(), ClassificationID);
        return View(dset1);
    }

Edit(POST) Action:

        [HttpPost]
    public ActionResult Edit(Reviewer.Models.ReviewEditModel model)
    {
        try
        {
            foreach (Reviewer.Models.QuestionEditModel qem in model.Questions)
            {
                if (qem.Answer == null || qem.OptionValue == null) { qem.completedBy = this.HttpContext.User.Identity.Name; }
            }

            if (ModelState.IsValid)
            {
                rr.SaveReviewEditModel(model);

                return RedirectToAction("Index");
            }
            else { return View(model); }
            }
        catch
        {
            return View(model);
        }
    }

Answer 1

You have to tell it what to actually render (<%: %>):

<% foreach (Reviewer.Models.QuestionEditModel qem in Model.Questions) { %>
     <%: Html.EditorFor(q=>qem, qem.EntryType, null) %>
<% } %>