Value null when binding a dropdownlist in mvc
<p>I am getting my head round mvc forms, and trying to bind a <code>DropDownList</code> in mvc but get this error:</p>

<blockquote>
  <p>Value cannot be null.<br>
      Parameter name: items</p>
</blockquote>

<p>On:</p>

<pre><code>@Html.DropDownListFor(x =&gt; x.JobRoles, new SelectList(Model.JobRoles, "value", "text"))
</code></pre>

<p>My controller:</p>

<pre><code>public ActionResult Create(ContactViewModel myViewData)
{
    List&lt;SelectListItem&gt; JobRoles_list = new List&lt;SelectListItem&gt;();
    JobRoles_list.Add(new SelectListItem
    {
        Text = "1",
        Value = "1"
    });
    // ViewBag.JobRoles = JobRoles_list;
    myViewData.JobRoles = JobRoles_list;
    return View(myViewData);
}
</code></pre>

<p>My model:</p>

<pre><code>public class ContactViewModel
{
    public List&lt;SelectListItem&gt; JobRoles { get; set; }
}
</code></pre>

<p>My view:</p>

<pre><code>@Html.DropDownListFor(x =&gt; x.JobRoles, new SelectList(Model.JobRoles, "value", "text"))
</code></pre>