Imports Infragistics.Win
Imports Infragistics.Win.UltraWinTabs
Imports Infragistics.Win.UltraWinTabbedMdi
Private Sub ultraTabbedMdiManager1_TabDragOver(ByVal sender As Object, ByVal e As Infragistics.Win.UltraWinTabbedMdi.MdiTabDragOverEventArgs) Handles ultraTabbedMdiManager1.TabDragOver
    ' The 'TabDragOver' event is invoked during a drag operation
    ' as the mouse is repositioned. The 'DropAction' indicates
    ' the action that will be taken if the mouse is released
    ' at this point.
    '
    Select Case e.DropAction
        Case MdiTabDropAction.TabGroup
            ' if the tab came from another tab group
            ' is attempting to drag it over an edit group,
            ' then prevent the drop
            If Not e.TabGroup Is e.Tab.TabGroup AndAlso e.TabGroup.Key = "Edit" Then
                ' The 'AllowDrop' may be set to false to indicate
                ' that the specified point is not a valid drop location.
                e.AllowDrop = False
                ' The 'DragCursor' may be used to show a specific cursor 
                ' for the 'Point' being processed.
                e.DragCursor = Cursors.No
            End If
            Exit Sub
        Case MdiTabDropAction.NewHorizontalGroup
        Case MdiTabDropAction.NewVerticalGroup
            ' the point must be over a splitter bar
            ' or near the edge of the mdi client area
            Exit Sub
        Case MdiTabDropAction.ContextMenu
            ' prevent the display of a context menu if
            ' the mouse is released within the mdi client area
            e.AllowDrop = False
            Exit Sub
    End Select
End Sub