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I'm trying to use a listview as a 'rolling log file'. It must hold the last 50 or so actions of the program. So if item 50 is added, item 0 must be deleted. So far OK. In the sample (borrowed from Peter Redei with some modifications...) if you press the Add line button, everything goes well (line added, first line deleted.) But if the right scroll bar is in the lowest position, adding a line scrolls the columnheaders off screen. I can solve this by using listview_update, or invalidaterect, but that introduces a lot of screen flickering if there are many lines added to the view. Is there another way to 'freeze' the columnheaders?
Peter.
Code:
'==============================================================================
'
' Testing listview routines
' David Morris 23/01/2000
' added some routines by Peter Redei
'==============================================================================
' ** Eliminate unnecessary macros
%NOANIMATE = 1 : %NODRAGLIST = 1 : %NOHEADER = 1 : %NOIMAGELIST = 1
'%NOLISTVIEW = 1
%NOTABCONTROL = 1 : %NOTRACKBAR = 1 : %NOTREEVIEW = 1 : %NOUPDOWN = 1
#Compile Exe
#Include "WIN32API.INC"
#Include "COMMCTRL.INC"
%IDOK = 1
%IDCANCEL = 2
%IDTEXT = 100
%BS_DEFAULT = 1
%IDLISTVIEW = 101
'%LVS_EX_TRACKSELECT = &H8 'Should be in your "COMMCTRL.INC"
'%LVS_EX_GRIDLINES = &H1 'Should be in your "COMMCTRL.INC"
'------------------------------------------------------------------------------
' Global variable to recieve the user name
Global UserName As String
Global hListView As Long
Global lviewSort As Integer
Type dField
fName As Asciiz * 80
Size As Integer
Alignment As Integer
End Type
Type ListData
Columns As Integer
Fields(0 To 80) As dField
End Type
'--------------------------------------------------------------------------------------------------
Function HitColumn (hList As Long, xdim As Long) As Long
Local i As Long, x As Long, sumx As Long
sumx = 0
i = 0
Do
x = ListView_GetColumnWidth(hList, i)
sumx = sumx + x
If xdim < sumx Then Function = i : Exit Do
Incr i
Loop
End Function
'--------------------------------------------------------------------------------------------------
Sub AppendListView (hList As Long, Rec() As String )
Dim z As Integer, iStatus As Integer, szStr As Asciiz * 300, lvi As LV_ITEM
Local x As Long
'this will be the next record
lvi.iItem = ListView_GetItemCount(hList) '+ 1
lvi.mask = %LVIF_TEXT
lvi.stateMask = %LVIS_FOCUSED '%LVIS_SELECTED
lvi.pszText = VarPtr(szStr)
For z = 0 To UBound(Rec)
szStr = Rec(z)
lvi.iSubItem = z
lvi.lParam = lvi.iItem
If z = 0 Then
lvi.mask = %LVIF_TEXT Or %LVIF_PARAM Or %LVIF_STATE
iStatus = ListView_InsertItem (hList, lvi)
Else
lvi.mask = %LVIF_TEXT
iStatus = ListView_SetItem (hList, lvi)
End If
Next
End Sub
'--------------------------------------------------------------------------------------------------
Sub ResetLParam(hList As Long)
Local i As Long, recs As Long, lvi As LV_ITEM, x As Long
lvi.mask = %LVIF_PARAM
lvi.iSubItem = 0
recs = ListView_GetItemCount(hList)
For i = 0 To recs - 1
lvi.iItem = i
x = ListView_GetItem (hList, lvi)
lvi.lParam = lvi.iItem
x = ListView_SetItem (hList, lvi)
Next
End Sub
'--------------------------------------------------------------------------------------------------
Function RetrieveLVData(hList As Long, Recno As Long, Fieldno As Long) As String
%cchTextMax = 300
Local lvi As LV_ITEM
Local value As Asciiz * 300
Local x As Long
lvi.cchTextMax = %cchTextMax
lvi.iItem = Recno
lvi.pszText = VarPtr(value)
lvi.iSubItem = Fieldno
lvi.Mask = %LVIF_TEXT
x = ListView_GetItem (hList, lvi)
Function = value
End Function
'--------------------------------------------------------------------------------------------------
Function compare(ByVal lParam1 As Long, ByVal lParam2 As Long, _
ByVal lParamsort As Long) As Integer
'The lParam1 parameter is the 32-bit value associated with the first item being compared; and the
'lParam2 parameter is the value associated with the second item. These are the values that were
'specified In the lParam member of the items' LV_ITEM structure when they were inserted into the
'list. The lParamSort parameter is the same value passed to the LVM_SORTITEMS message.
'The comparison function must return a negative value if the first item should precede the second,
'a positive value if the first item should follow the second, or zero if the two items are
'equivalent. lParam will carry a pointer to the value in the cell
Local value1 As Asciiz * 300, value2 As Asciiz * 300, j%
Function = 0
value1 = RetrieveLVData(hListView, lParam1, lParamsort)
value2 = RetrieveLVData(hListView, lParam2, lParamsort)
Select Case lviewSort
Case 0 'ascending
j = 1
Case Else 'descending
j = -1
End Select
If value1 < value2 Then
Function = -1 * j
ElseIf value1 = value2 Then
Function = 0
Else
Function = 1 * j
End If
End Function
'--------------------------------------------------------------------------------------------------
CallBack Function OkButton()
If ListView_GetItemCount(hListView) > 34 Then ListView_DeleteItem hListView, 0
Dim Rec (1) As String
Rec(0) = "One more"
Rec(1) = "line added!"
AppendListView hListView, Rec()
End Function
'--------------------------------------------------------------------------------------------------
CallBack Function CancelButton()
Dialog End CbHndl, 0
End Function
'--------------------------------------------------------------------------------------------------
CallBack Function ListViewProcess ()
If CbCtlMsg = %WM_LBUTTONDBLCLK Then
MsgBox "Double Click",48,"LISTVIEW 'NOT working
End If
End Function
'--------------------------------------------------------------------------------------------------
CallBack Function tstListView()
'LOCAL tbab AS TBADDBITMAP
Local ID As Long, hDlg As Long, lpToolTip As TOOLTIPTEXT Ptr, lData As ListData
Local my_LpLvNm As NM_LISTVIEW Ptr, hi As LV_HITTESTINFO, itemselect As Long, reclient As rect
Local pt As POINTAPI, i As Long, sText As String
Static zText As Asciiz * 255
'STATIC hBmp AS LONG
hDlg = CbHndl
Select Case CbMsg
Case %WM_INITDIALOG
Case %WM_NOTIFY
Select Case LoWrd(CbWparam)
Case %IDLISTVIEW
my_LpLvNm = CbLparam
If @my_LpLvNm.hdr.code = %LVN_COLUMNCLICK Then
itemselect = @my_LpLvNm.iSubItem 'HitColumn(hListView, hi.pt.x)
i = (itemselect = -1)
If i = 0 Then
'toggle ascending/descending
lviewSort = Not lviewSort
ListView_SortItems hListView, CodePtr(compare), itemselect
'lparam was set to the original 'recordnumber'
'now this changed, we need to set it to the new position
ResetLParam hListView
End If
ElseIf @my_LpLvNm.hdr.code = %NM_DBLCLK Then 'Now have Mouse Clicks!
SText = RetrieveLVData(hListView, @my_LpLvNm.iItem, 1) 'Next find where click was
Control Set Text hDlg&, %IDTEXT, Str$(CbCtlMsg)+Str$(CbWparam)+Str$(CbLparam)' sText
End If
'
' ElseIf @my_LpLvNm.hdr.code = %NM_DBLCLK Then 'Now have Mouse Clicks!
' sText = RetrieveLVData(hListView, 0, 0) 'Next find where click was
' MsgBox sText,48,"LISTVIEW"
' End If
End Select
End Select
End Function
'--------------------------------------------------------------------------------------------------
Function PbMain () As Long
$Register None
Local hDlg As Long, result As Long, zText As Asciiz * 255, icc As INIT_COMMON_CONTROLSEX
Local LVC As LV_COLUMN, i As Long,r As Long, c As Long,IStyle As Long
%NumCols = 5:%NumRows = 30
Dim Rec(%NumCols+1)As String
Local LVI As LV_ITEM
'%LVS_EX_TRACKSELECT = &H8
' InitCommonControls
icc.dwICC = %ICC_DATE_CLASSES Or %ICC_BAR_CLASSES Or %ICC_LISTVIEW_CLASSES
icc.dwSize = SizeOf(icc)
InitCommonControlsEx icc
' ** Create a new dialog template
Dialog New 0, "What is your name?", ,, 460, 250, 0, 0 To hDlg
' ** Add controls to it
Control Add Button, hDlg, %IDOK, "Add a line", 34, 32, 50, 14, %BS_DEFAULT Call OkButton
Control Add Button, hDlg, %IDCANCEL, "Cancel", 84, 32, 40, 14, 0 Call CancelButton
'$WC_LISTVIEW
Control Add "SysListView32", hDlg, %IDLISTVIEW,"",0,50,300,180, _
%WS_border Or %WS_Child Or %WS_visible Or _
%LVS_REPORT Or %LVS_SHOWSELALWAYS, _
%WS_EX_CLIENTEDGE Call ListViewProcess
Control Handle hDlg,%IDLISTVIEW To hListView
IStyle = SendMessage (hListView,%LVM_GETEXTENDEDLISTVIEWSTYLE, 0, 0)
IStyle = IStyle Or %LVS_EX_FULLROWSELECT Or %LVS_EX_TRACKSELECT Or %LVS_EX_GRIDLINES
SendMessage hListView, %LVM_SETEXTENDEDLISTVIEWSTYLE, 0, ByVal IStyle
lvC.mask = %LVCF_FMT Or %LVCF_WIDTH Or %LVCF_TEXT Or %LVCF_SUBITEM
lvC.fmt = %LVCFMT_LEFT
lvC.cx = 90
LVC.cchTextMax = 255
For c = 1 To %NumCols
zText = "Column " + Format$(c - 1)
LVC.pszText = VarPtr(zText)
Control Send hDlg,%IDLISTVIEW,%LVM_INSERTCOLUMN, c, VarPtr(lvc)
Next
For r = 1 To %NumRows
For c = 1 To %NumCols
rec(c-1) = "Row " + Format$(r) + " Col " + Format$(c-1)
Next c
AppendListView hListView, Rec()
Next r
' ** Display the dialog
Dialog Show Modal hDlg Call tstListView To Result
' ** Check the result
If result Then MsgBox "Hello " & UserName
End Function
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