Checkbox inside menu?

[Egbert Zijlema]

I don't like visible checkboxes in a well-designed GUI (transparent dialog with photograph as a background, for instance). They spoil the effect. Instead, I can use a menu with options that have either the %MF_CHECKED or the %MF_UNCHECKED state. It works, but for the user it may not be very clear what happens, because the checkmarks disappear/reappear "under water", so to speak.

Now I want to try to create a menu with checkboxes inside, replacing the normal checked/unchecked options. I guess that I should create an owner drawn menu. Unfort., I have not the slightest idea, where to start. Are there samples around here? A search for "checkbox menu" did not deliver anything usable, nor did a search for "owner drawn menu".

Thanks for any hint, help or code sample.

[Chris Holbrook]

Check out MENUITEMINFO in the Win32 API help

[Michael Mattias]

Or, you could make a dialog/window with which just looks like a menu and show it when the user would expect it.

Seems to me someone did an owner-drawn menu demo here just in the last couple of weeks, except it was NOT in the Source Code forum. Try a full text search on "%MF_OWNERDRAW" since that would have had to appear in the code. WM_MEASUREITEM would also have had to appear.

[Chris Boss]

The SetMenuItemBitmaps API function allows you to replace the standard checkmark images with your own custom bitmaps. You can do this by either drawing your own Bitmaps and use them, or by creating a blank bitmap in memory and drawing the checkbox images using the DrawFrameControl API function to draw your images.

DrawFrameControl is a very useful function, since it can draw any of the common window elements used by most controls.

The GetSystemMetrics API function is useful to determine the actual size a number of window elements should be. The SM_CXMENUCHECK and SM_CYMENUCHECK flags should be used to find the proper size for a check image for menus. Then use DrawFrameControl to draw it the correct size in a blank bitmap and then use that bitmap in SetMenuItemBitmap.

[Egbert Zijlema]

MENUITEMINFO is not the solution

When using SetMenuItemInfo (API) a coder can change the standard checkmark of a menu item into a bullet. Although defined as MFT_RADIOCHECK, it is not really a radio-button but a normal bullet, which is only displayed when the state of the menu-item is MF_CHECKED (MFS_CHECKED). It disappears when the state of the item becomes unchecked. In fact, same behaviour as standard checkmark. In other words: lots of fuss to create no change.

What I want to achieve is a real checkbox that can be checked/unchecked by the user. So I'm going to try Michael's suggestion now: a second dialog that pops up instead of the menu. This means that the original menu should be disabled (it never opens) but should nevertheless receive a notification message in order to launch the replacing dialog. How?

Thanks, guys, for all your help, so far.

[Edwin Knoppert]

Afaik a menu does not support checkboxes behaviour.
The radio it does and is a bullet.
You can 'uncheck' when the item is clicked and therefore make it work as a checkbox.

Other option is already suggested, ownerdrawn.

[Egbert Zijlema]

This code does not create the bitmaps

Well, I've made this pseudo code, but I don't see the checkbox appear.
I think something is wrong in respect with the memory device context stuff. Normally hDC = CreateCompatibleDC(0) should be followed by SelectObject hDC, hObject, but which handle of which object must we select, since the bitmap handles will be set later by DrawFrameControl API function?

#COMPILE EXE
#DIM ALL

#INCLUDE "WIN32API.INC"

%IDM_OPT1 = 1002

FUNCTION AttachMenu(BYVAL hDlg AS DWORD) AS DWORD
  LOCAL cxMnu AS LONG, cyMnu AS LONG
  LOCAL hDC AS DWORD, hBmp1 AS DWORD, hBmp2 AS DWORD, rt AS RECT
  LOCAL hMenu  AS DWORD
  LOCAL hPopUp AS DWORD

  MENU NEW BAR TO hMenu
  MENU NEW POPUP TO hPopUp
  MENU ADD POPUP, hMenu, "&Edit", hPopUp, %MF_ENABLED
  MENU ADD STRING, hPopUp, "Option1", %IDM_OPT1, %MF_ENABLED
  MENU ATTACH hMenu, hDlg

  hDC = CreateCompatibleDC(0)
  cxMnu = GetSystemMetrics(%SM_CXMENUCHECK)
  cyMnu = GetSystemMetrics(%SM_CYMENUCHECK)

  rt.nLeft = 0
  rt.nTop = 0
  rt.nRight = cxMnu - 1
  rt.nBottom = cyMnu - 1

  hBmp1 = DrawFrameControl(hDC, rt, %DFC_BUTTON, %DFCS_BUTTONCHECK OR %DFCS_CHECKED)
  hBmp2 = DrawFrameControl(hDC, rt, %DFC_BUTTON, %DFCS_BUTTONCHECK)

  SetMenuItemBitmaps hMenu, %IDM_OPT1, %MF_BYCOMMAND, hBmp2, hBmp1
  FUNCTION = hMenu
END FUNCTION

CALLBACK FUNCTION ShowDlgProc()
  SELECT CASE AS LONG CBMSG
    CASE %WM_COMMAND
      SELECT CASE AS LONG CBCTL
        CASE %IDM_OPT1
          MSGBOX "%IDM_OPT1 = " & FORMAT$(%IDM_OPT1), 64 OR %MB_TASKMODAL, " Bmp demo.."
      END SELECT
  END SELECT
END FUNCTION

FUNCTION PBMAIN()
  LOCAL hDlg AS DWORD, dwRet AS DWORD
  DIALOG NEW %HWND_DESKTOP, " Menu bitmap demo..", 70, 70, 201, 133, %WS_CAPTION OR %WS_MINIMIZEBOX OR %WS_SYSMENU TO hDlg
  dwRet = AttachMenu(hDlg)
  DIALOG SHOW MODAL hDlg, CALL ShowDlgProc
END FUNCTION

[Michael Mattias]

DrawFrameControl() is used at drawing time, not at menu creation time.

If the menu is MF_OWNERDRAW style, that would be on the WM_DRAWITEM notification, and you have to process the WM_MEASUREITEM notification, too.

[norbert doerre]

This is an old one, but it works!

'-------------------------------------------------------------------------------------------------------
' INCLUDE FILES
'-------------------------------------------------------------------------------------------------------
#If Not %Def(%WINAPI)
    #INCLUDE "WIN32API.INC"
#ENDIF

'-------------------------------------------------------------------------------------------------------
' FUNCTION DECLARATIONS
'-------------------------------------------------------------------------------------------------------
Declare Sub SwitchMenuItemCheck(sMenuString As String)
Declare Sub SetMenuItemCheck(sMenuString As String, lCheckState As long)
Declare Function GetMenuItemCheck(sMenuString As String) As long
Declare Function VCIsCurrentWorldValid Lib "VCMAIN32.DLL" Alias "VCIsCurrentWorldValid" () As Integer
Declare Function VCGethWndFrame Lib "VCMAIN32.DLL" Alias "VCGethWndFrame" () As Long
Declare Sub SetMenuChecksByDrawingSettings()

'-------------------------------------------------------------------------------------------------------
'  SUB GetMenuItemCheck
'-------------------------------------------------------------------------------------------------------
Function GetMenuItemCheck(sMenuString As String) As Long
	Local hWnd As Long
	Local hMenu As Long
	Local lMenuCount As Long
	Local lSubMenuCount As Long
	Local hSubMenu As Long
	Local ItemID As Long
	Local lRes As Long
	Local szMenuString As Asciiz * 64
	Local MainMenuIndex As Long
	Local SubMenuIndex As Long
	Local iState As Integer
	Function = %MF_UNCHECKED
	If VCIsCurrentWorldValid() = 0 Then Exit Function
	hWnd = VCGetHwndFrame() 'Mcadd frame handle
'	hMenu = GetSystemMenu(hWnd, 0) 'prüfen, ob Systemmenü aktiv
'	lSysMenuCount = GetMenuItemCount(hMenu) 'Anzahl der aktiven Systemmenü-Items
	hMenu = GetMenu(hWnd)	'Handle des Mcadd Hauptmenüs
	lMenuCount = GetMenuItemCount(hMenu) 'Anzahl der Untermenüs im Hauptmenü = 14 ohne Systemmenü, 18 mit Systemmenü
	For MainMenuIndex = 0 To lMenuCount -1
		hSubMenu = GetSubMenu(hMenu, MainMenuindex) 'Handle des Untermenüs mit Menütitel "Layer"
		lSubMenuCount = GetMenuItemCount(hSubMenu)
		For SubMenuIndex = 0 To lSubMenuCount - 1
			ItemID = GetMenuItemID(hSubMenu, SubMenuIndex)	'ID des ersten Menüeintrags im Untermenü 4
			lRes = GetMenuString(hSubMenu, ItemID, szMenuString, 0, %MF_BYCOMMAND) 'zuerst mit Parameter 0 nur die Länge ermitteln
			lRes = GetMenuString(hSubMenu, ItemID, szMenuString, lRes, %MF_BYCOMMAND) 'jetzt über die Länge den String ermitteln
			If InStr(szMenuString, sMenuString) Then
				iState = GetMenuState(hMenu, ItemID, %MF_BYCOMMAND Or %MF_CHECKED)
				Function = iState
				Exit For
			End If
		Next SubMenuIndex
	Next MainMenuIndex
End Function

'-------------------------------------------------------------------------------------------------------
'  SUB SetMenuItemCheck
'-------------------------------------------------------------------------------------------------------
Sub SetMenuItemCheck(sMenuString As String, iCheckVal As Long)
	'INPUT: iCheckVal = %MF_CHECKED oder iCheckVal = %MF_UNCHECKED
	'INPUT alternativ: iCheckVal = 1 oder iCheckVal = 0
	Local hWnd As Long
	Local hMenu As Long
	Local lMenuCount As Long
	Local lSubMenuCount As Long
	Local hSubMenu As Long
	Local ItemID As Long
	Local lRes As Long
	Local MainMenuIndex As Long
	Local SubMenuIndex As Long 
	Local szMenuString As Asciiz * 64
	If VCIsCurrentWorldValid() = 0 Then Exit Sub
	If iCheckVal = 0 Then 
		iCheckVal = %MF_UNCHECKED
	ElseIf iCheckVal = 1 Then
		iCheckVal = %MF_CHECKED
	End If
	hWnd = VCGetHwndFrame() 'Mcadd frame handle
'	hMenu = GetSystemMenu(hWnd, 0) 'prüfen, ob Systemmenü aktiv
'	lSysMenuCount = GetMenuItemCount(hMenu) 'Anzahl der aktiven Systemmenü-Items
	hMenu = GetMenu(hWnd)	'Handle des Mcadd Hauptmenüs
	lMenuCount = GetMenuItemCount(hMenu) 'Anzahl der Untermenüs im Hauptmenü = 14 ohne Systemmenü, 18 mit Systemmenü
	For MainMenuIndex = 0 To lMenuCount -1
		hSubMenu = GetSubMenu(hMenu, MainMenuindex) 'Handle des Untermenüs per MainMenuindex
		lSubMenuCount = GetMenuItemCount(hSubMenu)
		For SubMenuIndex = 0 To lSubMenuCount - 1
			ItemID = GetMenuItemID(hSubMenu, SubMenuIndex)	'ID des ersten Menüeintrags im Untermenü per SubMenuIndex
			lRes = GetMenuString(hSubMenu, ItemID, szMenuString, 0, %MF_BYCOMMAND) 'zuerst mit Parameter 0 nur die Länge ermitteln
			lRes = GetMenuString(hSubMenu, ItemID, szMenuString, lRes, %MF_BYCOMMAND) 'jetzt über die Länge den String ermitteln
			If InStr(szMenuString, sMenuString) Then
				lRes = CheckMenuItem(hSubMenu, ItemID, %MF_BYCOMMAND Or iCheckVal)
				Exit For
			End If
		Next SubMenuIndex
	Next MainMenuIndex
End Sub