Listview scroll position

[Barry Erick]

I can't quite find the solution to this.

I have a 2 column listview that can scroll. Right now, I just care about Horiz scroll.

I get the scroll bar position with

control handle cbhndl, ListviewID to hCtl
pos= GetScrollPos(hctl,%SB_HORZ)

and later

SetScrollPos(hCTL,%SB_HORZ,pos,-1)

But that only sets the scroll bar

Adding
ListView_Scroll (hCTL,pos,0) moves the listview, but this is in pixels and what is saved with GetScroll pos is not. Is there a way to get the ListView scroll position?

[Richard Angell]

removed original suggestion.

You probably will need to relate the scroll bar range to the pixel length it takes.
ListView_GetItemRect
GetScrollRange

[Richard Angell]

Barry,

It appears that the stock LV has a range in pixels 1 pixel off from the ListView_GetItemRect horizontal value. See CASE %WM_USER+100 in the demo code below. Does this help? Is your dialog or window in PIXELS?

#PBFORMS CREATED V1.51
#COMPILE EXE
#DIM ALL

#PBFORMS BEGIN INCLUDES
%USEMACROS = 1
#IF NOT %DEF(%WINAPI)
    #INCLUDE "WIN32API.INC"
#ENDIF
#IF NOT %DEF(%COMMCTRL_INC)
    #INCLUDE "COMMCTRL.INC"
#ENDIF
#INCLUDE "PBForms.INC"
#PBFORMS END INCLUDES

#PBFORMS BEGIN CONSTANTS
%IDLG_DIALOG1         =  101
%ILVC_SYSLISTVIEW32_1 = 1001
%ILBL_POSITION        = 1002
%IBTN_QUIT         = 1003
#PBFORMS END CONSTANTS

DECLARE CALLBACK FUNCTION ShowDIALOG1Proc()
DECLARE FUNCTION SampleListView(BYVAL hDlg AS DWORD, BYVAL lID AS LONG, BYVAL _
    lColCnt AS LONG, BYVAL lRowCnt AS LONG) AS LONG
DECLARE FUNCTION ShowDIALOG1(BYVAL hParent AS DWORD) AS LONG
#PBFORMS DECLARATIONS

FUNCTION PBMAIN()
    PBFormsInitComCtls (%ICC_WIN95_CLASSES OR %ICC_DATE_CLASSES OR _
        %ICC_INTERNET_CLASSES)

    ShowDIALOG1 %HWND_DESKTOP
END FUNCTION

CALLBACK FUNCTION ShowDIALOG1Proc()
    STATIC hListView AS DWORD
    LOCAL x,rslt AS LONG
    LOCAL lpMinPos,lpMaxPos  AS LONG

    SELECT CASE AS LONG CBMSG
        CASE %WM_INITDIALOG
            CONTROL HANDLE CBHNDL,%ILVC_SYSLISTVIEW32_1 TO hListView
            DIALOG POST CBHNDL,%WM_USER+100,0,0

        CASE %WM_USER+100
             rslt = GetScrollRange(hListView, %SB_HORZ,lpMinPos,lpMaxPos)
             CONTROL SEND CBHNDL,%ILVC_SYSLISTVIEW32_1,%LVM_SCROLL,500,0
             x = GetScrollPos(hListView, %SB_HORZ)
             CONTROL SET TEXT CBHNDL,%ILBL_POSITION,FORMAT$(x)

        CASE %WM_NCACTIVATE
            STATIC hWndSaveFocus AS DWORD
            IF ISFALSE CBWPARAM THEN
                hWndSaveFocus = GetFocus()
            ELSEIF hWndSaveFocus THEN
                SetFocus(hWndSaveFocus)
                hWndSaveFocus = 0
            END IF

        CASE %WM_COMMAND
            SELECT CASE AS LONG CBCTL
                CASE %ILVC_SYSLISTVIEW32_1

                CASE %ILBL_POSITION

                CASE %IBTN_QUIT
                    IF CBCTLMSG = %BN_CLICKED OR CBCTLMSG = 1 THEN
                        DIALOG END CBHNDL
                    END IF

            END SELECT
    END SELECT
END FUNCTION

FUNCTION SampleListView(BYVAL hDlg AS DWORD, BYVAL lID AS LONG, BYVAL lColCnt _
    AS LONG, BYVAL lRowCnt AS LONG) AS LONG
    LOCAL lCol   AS LONG
    LOCAL lRow   AS LONG
    LOCAL hCtl   AS DWORD
    LOCAL tLVC   AS LV_COLUMN
    LOCAL tLVI   AS LV_ITEM
    LOCAL szBuf  AS ASCIIZ * 32
    LOCAL lStyle AS LONG

    CONTROL HANDLE hDlg, lID TO hCtl

    lStyle = ListView_GetExtendedListViewStyle(hCtl)
    ListView_SetExtendedListViewStyle(hCtl, lStyle OR %LVS_EX_FULLROWSELECT _
        OR %LVS_EX_GRIDLINES)

    ' Load column headers.
    tLVC.mask    = %LVCF_FMT OR %LVCF_TEXT OR %LVCF_SUBITEM
    tLVC.fmt     = %LVCFMT_LEFT
    tLVC.pszText = VARPTR(szBuf)
    FOR lCol = 0 TO lColCnt - 1
        szBuf       = USING$("Column #", lCol)
        tLVC.iOrder = lCol
        ListView_InsertColumn(hCtl, lCol, tLVC)
    NEXT lCol

    ' Load sample data.
    FOR lRow = 0 TO lRowCnt - 1
        tLVI.stateMask = %LVIS_FOCUSED
        tLVI.pszText   = VARPTR(szBuf)
        tLVI.iItem     = lRow
        FOR lCol = 0 TO lColCnt - 1
            szBuf         = USING$("Column # Row #", lCol, lRow)
            tLVI.iSubItem = lCol
            tLVI.lParam   = lRow
            IF lCol = 0 THEN
                tLVI.mask = %LVIF_TEXT OR %LVIF_PARAM OR %LVIF_STATE
                ListView_InsertItem(hCtl, tLVI)
            ELSE
                tLVI.mask = %LVIF_TEXT
                ListView_SetItem(hCtl, tLVI)
            END IF
        NEXT lCol
    NEXT lRow

    ' Auto size columns.
    FOR lCol = 0 TO lColCnt - 2
        ListView_SetColumnWidth(hCtl, lCol, %LVSCW_AUTOSIZE)
    NEXT lCol
    ListView_SetColumnWidth(hCtl, lColCnt - 1, %LVSCW_AUTOSIZE_USEHEADER)
END FUNCTION

FUNCTION ShowDIALOG1(BYVAL hParent AS DWORD) AS LONG
    LOCAL lRslt  AS LONG

#PBFORMS BEGIN DIALOG %IDLG_DIALOG1->->
    LOCAL hDlg   AS DWORD
    LOCAL hFont1 AS DWORD
    LOCAL hFont2 AS DWORD

    DIALOG NEW hParent, "LV Horizontal Scroll Position", 322, 128, 400, 246, _
        %WS_POPUP OR %WS_BORDER OR %WS_DLGFRAME OR %WS_CAPTION OR _
        %WS_SYSMENU OR %WS_CLIPSIBLINGS OR %WS_VISIBLE OR %DS_MODALFRAME OR _
        %DS_3DLOOK OR %DS_NOFAILCREATE OR %DS_SETFONT, %WS_EX_CONTROLPARENT _
        OR %WS_EX_LEFT OR %WS_EX_LTRREADING OR %WS_EX_RIGHTSCROLLBAR, TO _
        hDlg
    CONTROL ADD "SysListView32", hDlg, %ILVC_SYSLISTVIEW32_1, _
        "SysListView32_1", 5, 5, 380, 200, %WS_CHILD OR %WS_VISIBLE OR _
        %WS_BORDER OR %WS_TABSTOP OR %LVS_REPORT OR %LVS_SINGLESEL OR _
        %LVS_SHOWSELALWAYS OR %LVS_EDITLABELS, %WS_EX_CLIENTEDGE OR _
        %WS_EX_LEFT OR %WS_EX_RIGHTSCROLLBAR
    CONTROL ADD LABEL,  hDlg, %ILBL_POSITION, "0", 10, 215, 120, 25
    CONTROL ADD BUTTON, hDlg, %IBTN_QUIT, "Quit", 330, 215, 50, 25

    hFont1 = PBFormsMakeFont("MS Sans Serif", 18, 700, %FALSE, %FALSE, _
        %FALSE, %ANSI_CHARSET)
    hFont2 = PBFormsMakeFont("MS Sans Serif", 18, 700, %FALSE, %TRUE, %FALSE, _
        %ANSI_CHARSET)

    CONTROL SEND hDlg, %ILBL_POSITION, %WM_SETFONT, hFont1, 0
    CONTROL SEND hDlg, %IBTN_QUIT, %WM_SETFONT, hFont2, 0
#PBFORMS END DIALOG

    SampleListView hDlg, %ILVC_SYSLISTVIEW32_1, 20, 100

    DIALOG SHOW MODAL hDlg, CALL ShowDIALOG1Proc TO lRslt

#PBFORMS BEGIN CLEANUP %IDLG_DIALOG1
    DeleteObject hFont1
    DeleteObject hFont2
#PBFORMS END CLEANUP

    FUNCTION = lRslt
END FUNCTION

[Michael Mattias]

It appears that the stock LV has a range in pixels 1 pixel off from the ListView_GetItemRect horizontal value

Retrieved RECT boundaries are always inclusive of the four points, making
Width = nRight - nLeft + 1.

[Barry Erick]

The problem was I was using SetScrollPos and not sending a message for the Listview with LVM_SETSCROLL

Thanks for the example.

[Richard Angell]

Right you are Michael.