Preventing Repaint/One Form from moving over another

[Jeff Waskiewicz]

Here is what I am trying to accomplish. I have an MDI application on the
left side of the client area I have a borderless form that holds a treeveiw
for navigation. When an item is selected from the treeview it opens a
seperate form. Similar to an MDI Windows Explorer. Now, I want to prevent
any for form from being moved into the area occupied by the navigation form.
I used the following code do do that...

Private Sub mdiChartDisplay_Move(ByVal sender As Object, _
ByVal e As System.EventArgs) Handles MyBase.Move
If g_frmChartDisplay.Left < g_mdiNavigation.Right Then
g_frmChartDisplay.Left = g_mdiNavigation.Width
End If
End Sub

....this works however a side effect is that when moving the form over the
navigation pane you see a the flicker/ghost image of the form over the
navigation pane while moving the form. I tried using WM_SETREDRAW to stop
repainting but this had a worse effect.

So my questions...

1) Is there a better way to prevent a form from moving into the area
occupied by another form?

2) Is there a way to prevent the flicker by suspending redraw or paint?

Thanks,

Jeff