title: Why is CascadeFrom() not doing anything?
body: <p>I'm really new to Kendo UI, and I'm having problems with <code>CascadeFrom()</code> not calling an action on my controller.  Here's the bare bones of my problem:</p>
  
  <pre><code>// The parent dropdown
  &lt;select id="Testing"&gt;
      &lt;option value="0"&gt;Vehicle&lt;/option&gt;
      &lt;option value="1"&gt;Driver&lt;/option&gt;
      &lt;option value="2"&gt;Trailer&lt;/option&gt;
  &lt;/select&gt;
  
  // The dynamic dropdown                                      
  @(Html.Kendo().DropDownListFor(m =&gt; m.VDTId)
      .DataValueField("Id")
      .DataTextField("Item")
      .DataSource(ds =&gt;
      {
          ds.Read(c =&gt; c.Action("GetVDT", "CompanyVDTUnavailability")
              .Data("getVDTSelection"))
              .ServerFiltering(true);
      })
      .CascadeFrom("Testing"))
  
  // Function to allow Kendo to pass a value to 
  // the type parameter of my GetVDT action.
  function getVDTSelection() {
      return {
          type: parseInt($("#Testing").val())
      };
  }
  </code></pre>
  
  <p>The action is being called when the page first loads, and returns the correct data.  The problem is, if I then make a selection from the <code>Testing</code> dropdown, the action is never invoked on the controller (I've verified this using a breakpoint on the action), meaning the dynamic dropdown never gets updated.</p>
  
  <p>Looking through the official example, and other questions around SO, I can't see what I'm doing wrong.  Could someone point me in the right direction, please?</p>
  
  <p><strong>Edit</strong>: I've tried Petur's solution below by changing the parent dropdown to the following:</p>
  
  <pre><code>@(Html.Kendo().DropDownListFor(m =&gt; m.Type)
      .Name("Testing")
      .DataValueField("Id")
      .DataTextField("Text")
      .BindTo(Model.UnavailabilityTypes))
  </code></pre>
  
  <p>This binds the parent dropdown correctly, but no longer invokes the controller action for the cascading dropdown even when the page first loads.  Any suggestions?</p>
  
  <p>Controller action signature as requested:</p>
  
  <pre><code>public JsonResult GetVDT(CompanyUnavailabilityType type)
  </code></pre>
  
  <p>Where <code>CompanyUnavailabilityType</code> is an enum.</p>