Cannot Access ViewModel Class member inside razor view - asp.net-mvc-4

Question

I cannot access a member of my class inside the view. All other members are accessible.
The following member "ListOfCategories" is not available in intellisense or at run time inside the view.
Error: There is no ViewData item of type 'IEnumerable' that has the key 'ListOfCategories'
My ViewModelClass
public class ArticleEditViewModel
{
public int ID { get; set; }
[Required]
public string Title { get; set; }
public List<Category> ListOfCategories = new List<Category>();
}
My Razor View
#model rrrr.ViewModels.Article.ArticleEditViewModel
#{
ViewBag.Title = "Edit";
Layout = "~/Views/Shared/_LayoutSecure.cshtml";
}
<div>
#Html.ActionLink("Back to Articles", "Index")
</div>
#using (Html.BeginForm()) {
#Html.AntiForgeryToken()
#Html.HiddenFor(model => model.ID)
<div class="tableHeader">
<h2>Update Article</h2>
</div>
<table id="RegistrationForm">
<tbody>
<tr>
<td>Title</td>
<td>
#Html.TextBoxFor(model => model.Title, new { #class = "registerinput" })
</td>
<td class="leftWarning">
#Html.ValidationMessageFor(model => model.Title)
</td>
</tr>
<tr>
<td>Category</td>
<td>
#Html.DropDownList(model => model.ListOfCategories, Model.CategoryID)
</td>
<td class="leftWarning">
#Html.ValidationMessageFor(model => model.CategoryID)
</td>
</tr>
<tr>
<td></td>
<td>
<input type="submit" value="Update Article" class = "css_button_4" />
</td>
</tr>
</tbody>
</table>
}

Answer 1

Use DropdownListFor instead. The code will be something like this:
#Html.DropDownListFor(model => model.CategoryId, Model.ListOfCategories.Select(c => new SelectListItem { Text = c.CategoryName, Value = c.CategoryId }))