When scrollbars are visible, panning gives the user the ability to click on the background of the control and move the contents around. The Sizer control must receive the MouseDown event in order to begin Panning. In some cases, you might have a control that covers up the background. To activate panning in this case, you will need to call the StartPanning method in the MouseDown event of that control. See the example below.

Example

Run the VB Sample Project Sample 1 and follow the steps below.

1. Select Dialog from the Show menu.
2. Click and drag under the word "Business" in the middle-right of the window (the scrollbars must be visible for this function to work).
3. Here is the code that initiates this function on the MouseDown event:

   
   Private Sub pic_MouseDown(Index As Integer, Button As Integer, Shift As Integer, X As Single, Y As Single)
      If asizer.Panning Then
         asizer.StartPanning
      End If
   End Sub 

Private Sub RepositionScrollbar(ctl As Control)
   Dim left As Long, top As Long
   Dim lRightEdge As Long, lLeftEdge As Long
   Dim lTopEdge As Long, lBottomEdge As Long
   If Not ctl.Container Is Me Then
      left = ctl.left + ctl.Container.left
      top = ctl.top + ctl.Container.top
   Else 
    left = ctl.left
      top = ctl.top
   End If
   lRightEdge = left + ctl.Width + scrollwidth
   If lRightEdge > asizer.ScrollPositionH + asizer.Width Then
      asizer.ScrollPositionH = lRightEdge - asizer.Width
   End If
   lLeftEdge = left - ctl.Width
   If lLeftEdge < asizer.ScrollPositionH Then
      asizer.ScrollPositionH = lLeftEdge
   End If
   lBottomEdge = top + ctl.Height + scrollwidth
   If lBottomEdge > asizer.ScrollPositionV + asizer.Height Then
      asizer.ScrollPositionV = lBottomEdge - asizer.Height
   End If
   lTopEdge = top - scrollwidth
   If lTopEdge < asizer.ScrollPositionV Then
      asizer.ScrollPositionV = lTopEdge
   End If
End Sub 

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