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The following code illustrates a problem using treeviews. If you select a node it sends a %TVN_SELCHANGING message to the WM_NOTIFY event handler. If you want to click the same treeview item again no message is sent. You have to move to another item in the treeview and then back again to make it fire (when using the mouse or using enter). Someone may know the answer without the code below.
To see the problem run the program and click a treenode. The caption bar will show the time. If you click a different node the time will change. If you click the same node twice several seconds apart the time will not change. How do you get around this?
Thanks,
Bob Mechler
To see the problem run the program and click a treenode. The caption bar will show the time. If you click a different node the time will change. If you click the same node twice several seconds apart the time will not change. How do you get around this?
Thanks,
Bob Mechler
Code:
#PBFORMS CREATED V1.51
#COMPILE EXE
#DIM ALL
'------------------------------------------------------------------------------
' ** Includes **
'------------------------------------------------------------------------------
#PBFORMS BEGIN INCLUDES
#IF NOT %DEF(%WINAPI)
#INCLUDE "WIN32API.INC"
#ENDIF
#IF NOT %DEF(%COMMCTRL_INC)
#INCLUDE "COMMCTRL.INC"
#ENDIF
#INCLUDE "PBForms.INC"
#PBFORMS END INCLUDES
'------------------------------------------------------------------------------
'------------------------------------------------------------------------------
' ** Constants **
'------------------------------------------------------------------------------
#PBFORMS BEGIN CONSTANTS
%IDD_DIALOG1 = 101
%TRV_SYSTREEVIEW32_1 = 1001
#PBFORMS END CONSTANTS
'------------------------------------------------------------------------------
'------------------------------------------------------------------------------
' ** Declarations **
'------------------------------------------------------------------------------
DECLARE CALLBACK FUNCTION ShowDIALOG1Proc()
DECLARE FUNCTION SampleTreeViewInsertItem(BYVAL hTree AS DWORD, BYVAL hParent _
AS DWORD, sItem AS STRING) AS LONG
DECLARE FUNCTION ShowDIALOG1(BYVAL hParent AS DWORD) AS LONG
#PBFORMS DECLARATIONS
'------------------------------------------------------------------------------
'------------------------------------------------------------------------------
' ** Main Application Entry Point **
'------------------------------------------------------------------------------
FUNCTION TVGetText(BYVAL hTree AS LONG, BYVAL hTVItem AS LONG) AS STRING
LOCAL zText AS ASCIIZ * 255
LOCAL lTVItem AS TV_ITEM
lTVItem.hItem = hTVItem
lTVItem.Mask = %TVIF_TEXT
lTVItem.pszText = VARPTR(zText)
lTVItem.cchTextMax = 255
TreeView_GetItem(hTree, lTVItem)
FUNCTION = zText
END FUNCTION
FUNCTION PBMAIN()
PBFormsInitComCtls (%ICC_WIN95_CLASSES OR %ICC_DATE_CLASSES OR _
%ICC_INTERNET_CLASSES)
ShowDIALOG1 %HWND_DESKTOP
END FUNCTION
'------------------------------------------------------------------------------
'------------------------------------------------------------------------------
' ** CallBacks **
'------------------------------------------------------------------------------
CALLBACK FUNCTION ShowDIALOG1Proc()
STATIC hTreeItem AS LONG,hTreeView AS LONG
DIM lpNmh AS NMHDR PTR
SELECT CASE AS LONG CBMSG
CASE %WM_INITDIALOG
' Initialization handler
CASE %WM_NCACTIVATE
STATIC hWndSaveFocus AS DWORD
IF ISFALSE CBWPARAM THEN
' Save control focus
hWndSaveFocus = GetFocus()
ELSEIF hWndSaveFocus THEN
' Restore control focus
SetFocus(hWndSaveFocus)
hWndSaveFocus = 0
END IF
CASE %WM_NOTIFY
SELECT CASE CBCTL
CASE %TRV_SYSTREEVIEW32_1
CONTROL HANDLE CBHNDL, %TRV_SYSTREEVIEW32_1 TO hTreeView&
lpNmh = CBLPARAM
IF @lpNmh.code = %TVN_SELCHANGING THEN
SetWindowText CBHNDL, TVGetText(hTreeView&, hTreeItem&) + TIME$
END IF
END SELECT
CASE %WM_COMMAND
' Process control notifications
SELECT CASE AS LONG CBCTL
CASE %TRV_SYSTREEVIEW32_1
END SELECT
END SELECT
END FUNCTION
'------------------------------------------------------------------------------
'------------------------------------------------------------------------------
' ** Sample Code **
'------------------------------------------------------------------------------
FUNCTION SampleTreeViewInsertItem(BYVAL hTree AS DWORD, BYVAL hParent AS _
DWORD, sItem AS STRING) AS LONG
LOCAL tTVItem AS TV_ITEM
LOCAL tTVInsert AS TV_INSERTSTRUCT
IF hParent THEN
tTVItem.mask = %TVIF_CHILDREN OR %TVIF_HANDLE
tTVItem.hItem = hParent
tTVItem.cchildren = 1
TreeView_SetItem hTree, tTVItem
END IF
tTVInsert.hParent = hParent
tTVInsert.Item.Item.mask = %TVIF_TEXT
tTVInsert.Item.Item.pszText = STRPTR(sItem)
tTVInsert.Item.Item.cchTextMax = LEN(sItem)
FUNCTION = TreeView_InsertItem(hTree, tTVInsert)
END FUNCTION
'------------------------------------------------------------------------------
'------------------------------------------------------------------------------
FUNCTION SampleTreeView(BYVAL hDlg AS DWORD, BYVAL lID AS LONG, BYVAL lCount _
AS LONG) AS LONG
LOCAL i AS LONG
LOCAL j AS LONG
LOCAL k AS LONG
LOCAL hCtl AS DWORD
LOCAL hRoot AS DWORD
LOCAL hParent AS DWORD
CONTROL HANDLE hDlg, lID TO hCtl
FOR i = 1 TO lCount
hRoot = SampleTreeViewInsertItem(hCtl, %NULL, USING$("Root#", i))
FOR j = 1 TO lCount
hParent = SampleTreeViewInsertItem(hCtl, hRoot, USING$("Item#", j))
FOR k = 1 TO lCount
CALL SampleTreeViewInsertItem(hCtl, hParent, USING$("SubItem#_.#", j, _
k))
NEXT k
NEXT j
NEXT i
END FUNCTION
'------------------------------------------------------------------------------
'------------------------------------------------------------------------------
' ** Dialogs **
'------------------------------------------------------------------------------
FUNCTION ShowDIALOG1(BYVAL hParent AS DWORD) AS LONG
LOCAL lRslt AS LONG
#PBFORMS BEGIN DIALOG %IDD_DIALOG1->->
LOCAL hDlg AS DWORD
DIALOG NEW hParent, "Dialog1", 90, 69, 399, 304, %WS_POPUP OR %WS_BORDER OR _
%WS_DLGFRAME 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 "SysTreeView32", hDlg, %TRV_SYSTREEVIEW32_1, "SysTreeView32_1", _
44, 28, 252, 184, %WS_CHILD OR %WS_VISIBLE OR %WS_TABSTOP OR _
%TVS_HASBUTTONS OR %TVS_HASLINES OR %TVS_LINESATROOT OR _
%TVS_SHOWSELALWAYS, %WS_EX_LEFT OR %WS_EX_CLIENTEDGE OR _
%WS_EX_RIGHTSCROLLBAR
#PBFORMS END DIALOG
SampleTreeView hDlg, %TRV_SYSTREEVIEW32_1, 3
DIALOG SHOW MODAL hDlg, CALL ShowDIALOG1Proc TO lRslt
#PBFORMS BEGIN CLEANUP %IDD_DIALOG1
#PBFORMS END CLEANUP
FUNCTION = lRslt
END FUNCTION
'------------------------------------------------------------------------------
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