Batch Editing ForeignKey Column error

[Matthew]

Without the foreignkey column my Grid works flawlessly.  It's a beautiful thing.  However, with the foreignkey column I get the following
error:
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Compilation Error
Description: An error occurred during the compilation of a resource required to service this request. Please review the following specific error details and modify your source code appropriately.

Compiler Error Message: CS0305: Using the generic type 'System.Collections.Generic.IEnumerable<T>' requires 1 type arguments

Source Error:

 

Line 13:         c.Bound(p => p.PowderNum).Width(90).Title("Number");
Line 14:         c.Bound(p => p.PowderName).Width(210).Title("Description");
Line 15:         c.ForeignKey(p => p.ColorId, (IEnumerable)ViewData["htmlcolors"], "ColorId", "HtmlName");
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I took apart the foreigh key column Demo and I can't find the source of the error in my code.... 
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View (snipit)
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@(Html.Telerik().Grid<Line.OpenAccess.Powders>()
    .Name("grid1")
    .DataKeys(k => k.Add(o => o.PowderId))
    .Columns(c =>{
        c.Bound(p => p.PowderNum).Width(90).Title("Number");
        c.Bound(p => p.PowderName).Width(210).Title("Description");
        c.ForeignKey(p => p.ColorId, (IEnumerable)ViewData["htmlcolors"], "ColorId", "HtmlName");
        //c.ForeignKey(p => p.VendorId, (IEnumerable<Line.OpenAccess.Vendors>)ViewData["Vendors"], "ID", "VendorName");
        c.Bound(p => p.Active).Width(60)
            .ClientTemplate("<input type='checkbox' name='Active' disabled='disabled' <#= Active? checked='checked' : '' #> />");
        c.Command(s => { s.Delete().ButtonType(GridButtonType.Image); });
        c.Bound(p => p.PowderId).ReadOnly().Hidden(true); //Hidden columns should be last
    })

    .ToolBar(commands => {
        commands.Insert()
            .ButtonType(GridButtonType.ImageAndText);
        commands.SubmitChanges()
            .ButtonType(GridButtonType.ImageAndText);
    })

    //.DataBinding(b => b.Server()
    .DataBinding(d => {
        d.Ajax()
        .Update("AjaxGridUpdates", "Powders")
        .Select("_ForeignKeyColumn", "Powders"); //VERY important
    })

    //Happens on client (ajax)
    .ClientEvents(e => {
        e.OnDataBinding("Grid_onDataBinding");
        e.OnError("Grid_onError");
    })

    .Editable(editing => editing.Mode(GridEditMode.InCell))
    .Pageable(pager => pager.PageSize(40))
    .Sortable()
    .Filterable()
    .KeyboardNavigation()
    .Scrollable(scroll => scroll.Height(500))
    .HtmlAttributes(new { style = "width:820px;" })
)

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Controller
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using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using Line.OpenAccess;
using Telerik.Web.Mvc;

namespace Line.Controllers
{
    public class PowdersController : Controller
    {

        LineEntities LineDB = new LineEntities();


        //View
        [GridAction]
        public ActionResult Index()
        {
            PopulateHtmlColors();
            return View();
        }

        /////////////////////////////////////////////////////////////////////////////////
        //   Ajax Binding Versions
        /////////////////////////////////////////////////////////////////////////////////

        private void PopulateHtmlColors()
        {
            //ViewData["htmlcolors"] = LineDB.Powders.ToList();

            ViewData["htmlcolors"] = new LineEntities().HtmlColors
                                                                                  .Select(e => new { ColorId = e.ColorId, HtmlName = e.HtmlName })
                                                                                  .OrderBy(e => e.HtmlName);
        }

        public ActionResult ForeignKeyColumn()
        {
            PopulateHtmlColors();
            return View();
        }

        [GridAction]
        public ActionResult _ForeignKeyColumn()
        {
            return View(new GridModel<Powders>
            {
                Data = this.LineDB.Powders.ToList()
            });
        }


        public ActionResult AjaxBinding()
        {
            return View(new GridModel<HtmlColors>
            {
                Data = this.LineDB.HtmlColors.ToList()
            });
        }


        //Ajax Binding
        [GridAction]
        public ActionResult _AjaxBinding()
        {
            return View(new GridModel<Powders> {
                Data = this.LineDB.Powders.ToList()
            });
        }

[Matthew]

After further testing I've confirmed the data is making it to the view.  I added the following to the top of the view and output the contents of the database...

<ul id="colors">
 @foreach (var color in ViewData["htmlcolors"] as List<Line.OpenAccess.HtmlColors>){
     <li>
        @color.ColorId, @color.HtmlName;
    </li>
 }
</ul>

[Rosen]

Hello Matthew,

Looking at the error you have mentioned it seems that System.Collections (the IEnumerable namespace) is not included on the page.

Best wishes,
Rosen
the Telerik team

[Matthew]

I added System.Collections to my controller.  It didn't help.  However, I did eventually find a syntax that would work.  I have attached my code.  My sample includes both the non-working code that matches the Telerik demo, and my functioning code commented out.

View
------------------------
@model IEnumerable<Line.OpenAccess.Parts>

@{
    ViewBag.Title = "Parts";
    Layout = "~/Views/Shared/_Layout.cshtml";
}
<h2>@ViewBag.Title</h2>

@(Html.Telerik().Grid(Model)
    .Name("grid1")
    .DataKeys(k => k.Add(o => o.PartId))
    .Columns(c =>{
        c.Bound(h => h.PartNum).Width(90).Title("Number");
        c.Bound(h => h.Revision).Width(60).Title("Rev");
        c.Bound(h => h.PiecesPer).Width(60).Title("QTY");
        //c.ForeignKey(h => h.PowderId, ViewData["powders"] as List<Line.OpenAccess.Powders>, "PowderId", "PowderName").Width(110).Title("Powder");
        c.ForeignKey(h => h.PowderId, (IEnumerable)ViewData["powders"], "PowderId", "PowderName").Width(110).Title("Powder");
        c.Bound(h => h.LineSpeed).Width(70).Title("Speed");


Controller
-----------------------------------------------
        private void PopulateComboBoxes() {

            ViewData["powders"] = LineDB.Powders
                                        .Select(e => new { PowderId = e.PowderId, PowderName = e.PowderName })
                                        .OrderBy(e => e.PowderName);

            //IEnumerable<Powders> powders = LineDB.Powders.ToList();
            //ViewData["powders"] = powders;
        }

While I found a partial solution, my syntax does not permit me to limit the fields being sent through ViewData or apply a sort.  I would like to get the demo syntax working.

[Rosen]

Hi Matthew,

I'm afraid that I do not see a System.Collections namespace included in the code snippet you have pasted? Please try the following highlighted change:

@model IEnumerable<Line.OpenAccess.Parts>

@{
    ViewBag.Title = "Parts";
    Layout = "~/Views/Shared/_Layout.cshtml";
}
<h2>@ViewBag.Title</h2>

@(Html.Telerik().Grid(Model)
    .Name("grid1")
    .DataKeys(k => k.Add(o => o.PartId))
    .Columns(c =>{
        c.Bound(h => h.PartNum).Width(90).Title("Number");
        c.Bound(h => h.Revision).Width(60).Title("Rev");
        c.Bound(h => h.PiecesPer).Width(60).Title("QTY");
        //c.ForeignKey(h => h.PowderId, ViewData["powders"] as List<Line.OpenAccess.Powders>, "PowderId", "PowderName").Width(110).Title("Powder");
        c.ForeignKey(h => h.PowderId, (System.Collections.IEnumerable)ViewData["powders"], "PowderId", "PowderName").Width(110).Title("Powder");
        c.Bound(h => h.LineSpeed).Width(70).Title("Speed");

Regards,
Rosen
the Telerik team