How to use passed select list in an editor template

Question

I'm trying to create an editor template that will create a "bootstrap style" radio buttons for each value from a passed select list (just like the Html.DropDownFor method create a dropdown list)

So i have the call in my view:

@Html.EditorFor(model => model.FaultTypeID,"RadioButtonList", 
        new SelectList(Model.AllowdeFaultTypes, "FaultTypeID", "FaultTypeName"))

and now the template of RadioButtonList:

@foreach (var item in ViewData["Items"] as SelectList)
{
    <a>@item.Text</a> <b>@item.Value</b>
}

but the conversion fails and i get a NullReferanceExeption. By reflection i see that the ViewData["Items"] value is of type System.Collections.Generic.List<CamelotFaultManagement.DAL.FaultType>

The problem is i really don't want to tightly couple the RadioButtonList editor template with CamelotFaultManagement.DAL.FaultType class, its just don't make any sense to do that. I want a generic editor template.

Answer 1

In your editor template you seem to be using some ViewData["Items"] property which you never set. If you want to use such property make sure you have assigned it:

@Html.EditorFor(
    model => model.FaultTypeID,
    "RadioButtonList", 
    new { Items = new SelectList(Model.AllowdeFaultTypes, "FaultTypeID", "FaultTypeName") }
)

This being said, your approach with using some ViewData stuff seems totally wrong to me.

I would simply define a view model (as always in ASP.NET MVC):

public class RadioListViewModel
{
    public string Value { get; set; }
    public IEnumerable<SelectListItem> Values { get; set; }
}

and then you could have your editor template strongly typed to this view model. Of course your editor template will be now stored in ~/Views/Shared/EditorTemplates/RadioListViewModel.cshtml:

@model IRadioListViewModel
@foreach (var item in Model)
{
    <a>@item.Text</a> <b>@item.Value</b>
}

and now all that's left is to use this view model in your main view model:

public class MyViewModel
{
    public RadioListViewModel FaultTypes { get; set; }
    ...
}

and then inside your view simply render the corresponding editor template:

@model MyViewModel
...
@Html.EditorFor(x => x.FaultTypes)

Simple, conventional, strongly typed.