Login
Templates, Tools and Utilities
for Clarion Developers
Templates, Tools and Utilities
|
||
|
|
|
Add a comment to an Icetips ArticlePlease add your comments to this article.
Please note that you must provide both a name and a valid email address in order
for us to publish your comment. Comments are moderated and are not visible until they have been approved. Spam is never approved!
Back to article list Search Articles Add Comment Printer friendly Direct link Par2: Check for multiple instances of a program 2000-01-16 -- Alexey Solovjev Far ago I posted an example of the program which uses mutex objects to
find another its instance. Attached one is its extension which uses
SetProp/GetProp functions to get a handle of first instance's window
from another program instance (really, in this way mutex objects become
unnecessary).
--------------------------------------------------------------------------------
PROGRAM
OMIT ('=== 16 bit', _WIDTH32_)
This program uses 32 bit specific API calls
! === 16 bit
HANDLE EQUATE(UNSIGNED)
HWND EQUATE(HANDLE)
DWORD EQUATE(LONG)
BOOL EQUATE(SIGNED)
LPARAM EQUATE(LONG)
SW_RESTORE EQUATE(9)
ERROR_ALREADY_EXISTS EQUATE(183)
MAP
MODULE('')
CreateMutex (<*DWORD>, BOOL, <*CSTRING>),HANDLE,RAW,PASCAL,NAME('CreateMutexA')
CloseHandle (HANDLE),BOOL,PROC,PASCAL,NAME('CloseHandle')
GetLastError (),DWORD,PASCAL,NAME('GetLastError')
GetDesktopWindow (),HWND,PASCAL,NAME('GetDesktopWindow')
GetWindowText (HWND,*CSTRING,SIGNED),SIGNED,RAW,PROC,PASCAL,NAME('GetWindowTextA')
SetProp (HWND,*CSTRING,HANDLE),BOOL,RAW,PROC,PASCAL,NAME('SetPropA')
GetProp (HWND,*CSTRING),HANDLE,RAW,PASCAL,NAME('GetPropA')
RemoveProp (HWND,*CSTRING),HANDLE,RAW,PROC,PASCAL,NAME('RemovePropA')
IsIconic (HWND),BOOL,PASCAL,NAME('IsIconic')
ShowWindow (HWND,SIGNED),BOOL,PROC,PASCAL,NAME('ShowWindow')
SetForegroundWindow (HWND),BOOL,PROC,PASCAL,NAME('SetForegroundWindow')
END
ShutProc()
Main()
TestInst(),BOOL
SwitchToOther(),BOOL
END
IDString CSTRING('00000ABC000') ! Some program ID string
AppMutexH HANDLE(0)
PropSet BOOL(FALSE)
CODE
SHUTDOWN (ShutProc)
IF NOT TestInst()
IF SwitchToOther()
RETURN
END
END
Main()
RETURN
! ===================================================================
ShutProc PROCEDURE()
CODE
IF AppMutexH <> 0
CloseHandle (AppMutexH)
AppMutexH = 0
END
IF PropSet
RemoveProp (GetDesktopWindow(), IDString)
PropSet = FALSE
END
! ===================================================================
TestInst PROCEDURE()
CODE
AppMutexH = CreateMutex (, FALSE, IDString)
RETURN CHOOSE (GetLastError() <> ERROR_ALREADY_EXISTS)
! ===================================================================
SwitchToOther PROCEDURE()
OtherInstFrame HWND,AUTO
Info CSTRING(128),AUTO
CODE
OtherInstFrame = GetProp (GetDesktopWindow(), IDString)
IF OtherInstFrame = 0
MESSAGE ('Property is FALSE')
RETURN FALSE
END
GetWindowText (OtherInstFrame, Info, SIZE (Info))
MESSAGE (Info, OtherInstFrame)
SetForegroundWindow (OtherInstFrame)
IF IsIconic (OtherInstFrame)
ShowWindow (OtherInstFrame, SW_RESTORE)
END
RETURN TRUE
! ===================================================================
Main PROCEDURE()
W0 APPLICATION('One Instance Test Program'),AT(,,280,100),FONT('MS Sans Serif',8,,FONT:regular),SYSTEM,
|
RESIZE,ICON(ICON:Application),MAX
TOOLBAR,AT(0,0,,30)
BUTTON('&Close'),AT(8,7,45,14),USE(?Close),STD(STD:Close)
END
END
hWnd HWND,AUTO
CODE
OPEN (W0)
hWnd = W0 {PROP:Handle}
SetProp (GetDesktopWindow(), IDString, hWnd)
PropSet = TRUE
W0 {PROP:Text} = W0 {PROP:Text} & ' - ' & hWnd
ACCEPT
END
CLOSE (W0)
Today is November 21, 2024, 7:22 am This article has been viewed 35216 times.
|
|