Public Class Form1
   Private pOpacity As Double
 
   Private Sub Form1_Deactivate(ByVal sender As System.Object, ByVal e As _
     System.EventArgs) Handles MyBase.Deactivate
      Me.Opacity = pOpacity
   End Sub
 
   Private Sub Form1_Activated(ByVal sender As System.Object, ByVal e As _
     System.EventArgs) Handles MyBase.Activated
      Me.Opacity = 1
   End Sub
 
   Private Sub TrackBar1_Scroll(ByVal sender As System.Object, ByVal e As _
     System.EventArgs) Handles TrackBar1.Scroll
      pOpacity = Me.TrackBar1.Value / 100
   End Sub
End Class