title: Populate Field based on another Combo Box
body: <p>I have a form (MS-Access 2003) that has three combo boxes. 1st (Category), 2nd (CatDetail), 3rd (NbrValue).  I have no problem populating 2nd with an after update event from 1st.  My problem comes in when I try to run a similar update event for the 2nd to update the 3rd.  Here is my code.</p>
  
  <p>Table 1 (Category)</p>
  
  <pre><code>CategoryID    Category Name
  1             Vacation
  2             DH
  </code></pre>
  
  <p>1st combo box (Category) SQL</p>
  
  <pre><code>SELECT Category.CategoryID, Category.[Category Name]
  FROM Category
  ORDER BY Category.[Category Name];
  </code></pre>
  
  <p>After Update VBA for 1st combo box (Category)</p>
  
  <pre><code>Option Compare Database
  Private Sub Category_AfterUpdate()
  Me.CatDetail = Null
  Me.CatDetail.Requery
  Me.CatDetail = Me.CatDetail.ItemData(0)
  End Sub
  </code></pre>
  
  <p>Table 2 (CatDetail)</p>
  
  <pre><code>CatDetail ID    CatDetail         Category
  1               Vac Day Used      Vacation
  2               Partial Vac Day   Vacation
  3               DH Gain           DH
  4               DH Used           DH
  </code></pre>
  
  <p>2nd Combo Box SQL (CatDetail)</p>
  
  <pre><code>SELECT CatDetail.[CatDetail ID], CatDetail.[CatDetail Name], CatDetail.CategoryID
  FROM CatDetail
  WHERE (((CatDetail.CategoryID)=[Forms]![Combo Form]![Category]));
  </code></pre>
  
  <p>After Update VBA for 2nd Combo box (CatDetail)</p>
  
  <pre><code>Private Sub CatDetail_AfterUpdate()
  Me.NbrValue = Null
  Me.NbrValue.Requery
  Me.NbrValue = Me.NbrValue.ItemData(0)
  End Sub
  </code></pre>
  
  <p>This portion works great.  I am lost with the next set to get the 3rd combo box to update.</p>
  
  <p>Table 3 (Value)</p>
  
  <pre><code>ValueID     Value    CatDetail Name
  1           -1       Vac Day Used
  2           -0.5     Partial Vac Day
  3           1        DH Gain
  4           -1       DH Used
  </code></pre>
  
  <p>3rd combo box (NbrValue) SQL</p>
  
  <pre><code>SELECT Value.ValueID, Value.Value, Value.[CatDetail Name]
  FROM [Value]
  WHERE (((Value.[CatDetail Name])=[Forms]![Combo Form]![CatDetail]));
  </code></pre>
  
  <p>To summarize, I can select my 1st combo box value.  After that selection the 2nd combo box updates with all corresponding values. The trouble is with the after update event on teh 2nd combo box as my 3rd combo box comes back Blank.</p>