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POResizing a ListBox on Drag and Drop
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copied!<p>I have several listboxes in a form that I can drag and drop items between. The drag and drop part of the code seems to work fine. Upon dropping an item into a listbox, I have a listbox resize procedure go through and resize the listboxes to fit their contents. The problem that I am running into is that upon dragging an item from LB1 (for example) to LB2, LB1 resizes as if it had one extra item in it's list. I would like to prevent that, but I'm not sure how. Here's the resize code:</p> <pre><code> Private Sub ListBox_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles ListBox1.MouseDown, ListBox2.MouseDown Dim Lbx As ListBox = sender Dim Pt As New Point(e.X, e.Y) ' Returns coords of mouse Dim Idx As Integer Dim retval As DragDropEffects ' Determine which listbox item was dragged Idx = Lbx.IndexFromPoint(Pt) ' Start a Drag and drop with that item If Idx >= 0 Then ' retval = Lbx.DoDragDrop(Lbx.Items(Idx), DragDropEffects.All) Debug.WriteLine(retval) If retval And DragDropEffects.Move Then Lbx.Items.RemoveAt(Idx) End If End If End Sub Private Sub ListBox_DragEnter(ByVal sender As Object, ByVal e As System.Windows.Forms.DragEventArgs) Handles ListBox1.DragEnter, ListBox2.DragEnter If (e.Data.GetDataPresent(DataFormats.Text)) Then e.Effect = DragDropEffects.Move Or DragDropEffects.Copy End If End Sub Private Sub ListBox_DragDrop(ByVal sender As Object, ByVal e As System.Windows.Forms.DragEventArgs) Handles ListBox1.DragDrop, ListBox2.DragDrop Dim LB As ListBox = sender LB.Items.Add(e.Data.GetData("Text")) QueueResize() End Sub </code></pre> <p>And here is the code for the resize:</p> <pre><code> Private Sub QueueResize() For Each cont As System.Windows.Forms.Control In Panel1.Controls If cont.GetType.ToString = "System.Windows.Forms.ListBox" Then Dim LB As ListBox = cont On Error GoTo ErrHandler Dim lItemHeight As Long Dim lRet As Long Dim lItems As Long Dim sngTwips As Single Dim sngLBHeight As Single If LB.Items.Count = 0 Then LB.Height = 25 'Return True Else lItems = LB.Items.Count lItemHeight = LB.ItemHeight If lItemHeight > 0 Then LB.Height = lItemHeight * lItems + 5 'AutoSizeLBHeight = True End If End If End If Next ErrHandler: End Sub </code></pre> <p>Any help would be appreciated! Thanks in advance.</p>

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