title: Add item to listbox from another form
body: <p>I'm trying to add items to listbox from another form but the listbox doesn't seem to update.</p>
  
  <p>I have 3 form : frm1, frm2, frm3</p>
  
  <p>this my code in frm1 to open frm2:</p>
  
  <pre class="lang-vb prettyprint-override"><code>Using frm As New frm2
      frm.ShowDialog()
  End Using
  </code></pre>
  
  <p>frm2 has a listbox named list_xxx</p>
  
  <p>code in frm3:</p>
  
  <pre class="lang-vb prettyprint-override"><code>Private Sub add_item()
      frm2.list_xxx.add("aaaa")
  End Sub
  </code></pre>
  
  <p>i want to add item to frm2 from frm3. but no success the listbox still empty.
  how to fix it?</p>