Date: 02-16-2022
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created by gbSnippets
'When a user clicks a "CheckMark" style menu, here's how to flip the check state.
'as you can see, they are lots of ways to do it - here are 6 approaches.
'See the Menu Skeleton for a compilable example using Example#1
'Primary Code:
'I prefer the approach that uses a Global variable. This has two advantages -
'creating a variable whose value can be saved/restored in an INI file, and used
'elsewhere in the program to direct program flow according the whether the
'menu is checked or not.
gMenuItem& = gMenuItem& XOR 1 'flip between 0 and 1
Menu Set State hMenuOptions, ByCmd %IDM_MenuItem, gMenuItem& * 8
'Here are 5 other ways to do it.
'Credit: Michael Mattias, Charles Dietz, Scott Slater
'Example#1
'get the state (returns either 0 or 8)
Menu Get State hMenuOptions, ByCmd %ID_Backup To iReturn 'get the state
Menu Set State hMenuOptions, ByCmd %ID_Backup, ABS(IsFalse iReturn)*8 'flip the state
'Example#2
'this is the brute force approach
Menu Get State hMenuOptions, ByCmd %IDM_MenuITem To iReturn 'get the state
If iReturn = 0 Then
Menu Set State hMenuOptions, ByCmd %IDM_MenuItem, 8 'flip the state
Else
Menu Set State hMenuOptions, ByCmd %IDM_MenuItem, 0 'flip the state
End If
'Example#3 - idea from Michael Mattias
Menu Get State hMenuOptions, ByCmd %IDM_MenuITem To iReturn 'get the state
Menu Set State hMenuOptions, ByCmd %IDM_MenuItem, _
IIF&(iReturn AND %MF_CHECKED, %MF_UNCHECKED, %MF_CHECKED) 'flip the state
'Example#4 - idea from Charles Dietz
Menu Get State hMenuOptions, ByCmd %IDM_MenuITem To iReturn 'get the state
Menu Set State hMenuOptions, ByCmd %IDM_MenuItem, _
IIF&(iReturn = %MF_Checked, %MF_UNCHECKED, %MF_CHECKED) 'flip the state
'Example#5 - idea from Scott Slater
'0 state means all bits are zero mask$ = 0
'8 state means all bits are zero except bit 3
'mask with both bits 1, all others zero, is 8+1 = 9
'9 could be replaced by %MF_Checked OR %MF_UnChecked
Menu Get State hMenuOptions, ByCmd %IDM_MenuITem To iReturn 'get the state
Menu Set State hMenuOptions, ByCmd %IDM_MenuItem, iReturn XOR 9 'flip the state of bit 0 and bit 3
'Menu Set State hMenuOptions, ByCmd %IDM_MenuItem, iReturn XOR (%MF_Checked Or %MF_Unchecked) 'alternate
'This compilable example creates an Option menu, with sub-menus.
'The two Option menus include code to toggle the checkmark state of the sub-menus
'The Callback code to respond to the menu clicks is also shown (puts menu name in the label)
'Compilable Example: (Jose Includes)
#Compiler PBWin 9, PBWin 10
#Compile EXE
#Dim All
%Unicode=1
#Include "Win32api.inc"
%IDM_ConfirmDelete = 600 : %IDM_SavePosition = 601
%IDC_TextBox = 900
Global hDlg As DWord, hMenu As DWord, hMenuOptions As DWord
Global ConfirmDelete&, SavePosition&
Function PBMain()
Dialog New Pixels, 0, "MRU Demo",300,300,300,200, %WS_OverlappedWindow To hDlg
Control Add TextBox, hDlg, %IDC_TextBox, " Selected menu item to toggle its state.", 30,30,240,125, %WS_Border
Menu New Bar To hMenu
Menu Attach hMenu, hDlg
Menu New Popup To hMenuOptions
Menu Add Popup, hMenu, "&Options", hMenuOptions, %MF_Enabled
Menu Add String, hMenuOptions, "&Confirm Delete", %IDM_ConfirmDelete, %MF_Enabled
Menu Add String, hMenuOptions, "&Save Position", %IDM_SavePosition, %MF_Enabled
Dialog Show Modal hDlg Call DlgProc()
End Function
CallBack Function DlgProc() As Long
Local temp$, iReturn&
Select Case CB.Msg
Case %WM_Command
Select Case CB.Ctl
Case %IDM_ConfirmDelete
ConfirmDelete& = ConfirmDelete& XOR 1 'flips global variable state 0/1
Menu Set State hMenuOptions, ByCmd %IDM_ConfirmDelete, ConfirmDelete&*8 'flip the menu checkstate
Case %IDM_SavePosition
SavePosition& = SavePosition& XOR 1 'flips global variable state 0/1
Menu Set State hMenuOptions, ByCmd %IDM_SavePosition, SavePosition&*8 'flip the state
End Select
End Select
End Function
'gbs_00200
'Date: 03-10-2012
http://www.garybeene.com/sw/gbsnippets.htm