Auto Scrolling a Treeview by mouse position - Refresh problem

[asilcott]

Longtime AutoIt fan, novice programmer and forum user.  Please let me know if there is anything I should be doing differently.

I am working on a program where I drag an item from a listview and drop it onto a treeview.  All is well with my drag and drop, but I am stuck trying to add a feature that will automatically scroll when the user drags an item to the bottom or the top of the treeview.  I can get the treeview to auto-scroll, but the last treeview item just repeats.  I am sure there is an easy way to refresh the treeview during scrolling that I am just not finding. 

The included example doesn't have any drag and drop.  Just moving your mouse to the bottom or top of the treeview will show my problem.  Any help would be greatly appreciated.

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#include <GUIConstantsEx.au3>
#include <WindowsConstants.au3>
#include <GuiTreeView.au3>
#include <GuiScrollBars.au3>
#include <ScrollBarConstants.au3>

Global $iScrollUp=False
Global $iScrollDown=False


;Create GUI
$hWnd = GUICreate("Auto Scroll Treeview", 300, 600, (@DesktopWidth/2)-150, (@DesktopHeight/2)-300, BitOR($WS_SIZEBOX,$WS_SYSMENU,$WS_MINIMIZEBOX,$WS_MAXIMIZEBOX))

;Create Treeview
Global $iTreeView = GUICtrlCreateTreeView(0, 0, 300, 600, BitOR($TVS_HASBUTTONS,$TVS_HASLINES,$TVS_LINESATROOT,$TVS_SHOWSELALWAYS,$WS_GROUP,$WS_TABSTOP), $WS_EX_CLIENTEDGE)
Global $hTreeView = GUICtrlGetHandle($iTreeView)
   
;Initialize Scrollbar
_GUIScrollBars_Init($hTreeView)

;Populate Treeview

_GUICtrlTreeView_BeginUpdate($hTreeView)
For $i=0 To 200
   _GUICtrlTreeView_Add($hTreeView, 0, "Item" & $i,0,0)
Next
_GUICtrlTreeView_EndUpdate($hTreeView)

GUISetState()

While 1
   $Msg = GUIGetMsg()
   Select
      Case $Msg = $GUI_EVENT_CLOSE
         Exit
      Case $GUI_EVENT_MOUSEMOVE
         Local $tMPos = _WinAPI_GetMousePos(True, $hTreeView)
         
         If DllStructGetData($tMPos, 2) <= 30 Then
            ;mouse moved into upper portion of treeview, set flag to scroll up
            $iScrollUp=True
            $iScrollDown=False
         ElseIf DllStructGetData($tMPos, 2) >= 540 Then
            ;mouse moved into lower portion of treeview, set flag to scroll down
            $iScrollUp=False
            $iScrollDown=True
         Else
            ;mouse is not in either upper or lower portion of treeview, so don't move
            $iScrollUp=False
            $iScrollDown=False
         EndIf
   EndSelect
   
   If $iScrollUp Then
      If _GUIScrollBars_GetScrollInfoPos($hTreeview, $SB_VERT) <> _GUIScrollBars_GetScrollInfoMin($hTreeview, $SB_VERT) Then
         ;Move scrollbar up 1
         ;_GUIScrollBars_ScrollWindow($hTreeView, 0, 1)
          _GUIScrollBars_SetScrollInfoPos($hTreeview, $SB_VERT, _GUIScrollBars_GetScrollInfoPos($hTreeview, $SB_VERT)-1)
      EndIf
      Sleep(50)
   EndIf

   If $iScrollDown Then
      If _GUIScrollBars_GetScrollInfoPos($hTreeview, $SB_VERT) <> _GUIScrollBars_GetScrollInfoMax($hTreeview, $SB_VERT) Then
         ;Move scrollbar down 1
        ;_GUIScrollBars_ScrollWindow($hTreeView, 0, -1)
         _GUIScrollBars_SetScrollInfoPos($hTreeview, $SB_VERT, _GUIScrollBars_GetScrollInfoPos($hTreeview, $SB_VERT)+1)
      EndIf
      Sleep(50)
   EndIf
WEnd

Edited November 7, 2013 by asilcott

[kylomas]

asilcot,

Try this,

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#include <GUIConstantsEx.au3>
#include <WindowsConstants.au3>
#include <GuiTreeView.au3>
#include <GuiScrollBars.au3>
#include <ScrollBarConstants.au3>

Global $iScrollUp=False
Global $iScrollDown=False


;Create GUI
$hWnd = GUICreate("Auto Scroll Treeview", 300, 600, (@DesktopWidth/2)-150, (@DesktopHeight/2)-300, BitOR($WS_SIZEBOX,$WS_SYSMENU,$WS_MINIMIZEBOX,$WS_MAXIMIZEBOX))

;Create Treeview
Global $iTreeView = GUICtrlCreateTreeView(0, 0, 300, 600, BitOR($TVS_HASBUTTONS,$TVS_HASLINES,$TVS_LINESATROOT,$TVS_SHOWSELALWAYS,$WS_GROUP,$WS_TABSTOP), $WS_EX_CLIENTEDGE)
Global $hTreeView = GUICtrlGetHandle($iTreeView)

;Initialize Scrollbar
_GUIScrollBars_Init($hTreeView)

;Populate Treeview

_GUICtrlTreeView_BeginUpdate($hTreeView)
For $i=0 To 200
   _GUICtrlTreeView_Add($hTreeView, 0, "Item" & $i,0,0)
Next
_GUICtrlTreeView_EndUpdate($hTreeView)

GUISetState()

While 1
   $Msg = GUIGetMsg()
   Select
      Case $Msg = $GUI_EVENT_CLOSE
         Exit
      Case $GUI_EVENT_MOUSEMOVE
         Local $tMPos = _WinAPI_GetMousePos(True, $hTreeView)

         If DllStructGetData($tMPos, 2) <= 30 Then
            ;mouse moved into upper portion of treeview, set flag to scroll up
            $iScrollUp=True
            $iScrollDown=False
         ElseIf DllStructGetData($tMPos, 2) >= 540 Then
            ;mouse moved into lower portion of treeview, set flag to scroll down
            $iScrollUp=False
            $iScrollDown=True
         Else
            ;mouse is not in either upper or lower portion of treeview, so don't move
            $iScrollUp=False
            $iScrollDown=False
         EndIf
   EndSelect

   If $iScrollUp Then

      If _GUIScrollBars_GetScrollInfoPos($hTreeview, $SB_VERT) <> _GUIScrollBars_GetScrollInfoMin($hTreeview, $SB_VERT) Then
         ;Move scrollbar up 1
         ;_GUIScrollBars_ScrollWindow($hTreeView, 0, 1)
          _GUIScrollBars_SetScrollInfoPos($hTreeview, $SB_VERT, _GUIScrollBars_GetScrollInfoPos($hTreeview, $SB_VERT)-1)
        _GUICtrlTreeView_EndUpdate($hTreeView)  ; <-------------   added to re-draw treeview
      EndIf
      ;Sleep(50)
   EndIf

   If $iScrollDown Then
      If _GUIScrollBars_GetScrollInfoPos($hTreeview, $SB_VERT) <> _GUIScrollBars_GetScrollInfoMax($hTreeview, $SB_VERT) Then
         ;Move scrollbar down 1
        ;_GUIScrollBars_ScrollWindow($hTreeView, 0, -1)
         _GUIScrollBars_SetScrollInfoPos($hTreeview, $SB_VERT, _GUIScrollBars_GetScrollInfoPos($hTreeview, $SB_VERT)+1)
        _GUICtrlTreeView_EndUpdate($hTreeView)  ; <------------- added to re-draw treeview
      EndIf
      ;Sleep(50)
   EndIf
WEnd

kylomas

edit: there is an interesting discussion of a related issue >here...

I tried the alternate suggestions from this thread but they did not work.  Maybe scrollbars are a different animal, don't know, never used them.

Edited November 8, 2013 by kylomas

[asilcott]

Ugh, this is exactly why I don't ask for help. The answer was so simple that now I look like an idiot!

One other thing I added to my Treeview to make the scrolling smoother was $WS_EX_COMPOSITED.

Thanks a ton for the help, kylomas.

[kylomas]

asilcott,

Glad to help and you do NOT look like an idiot, there is a difference between stubborness and determination.

kylomas