Hi Thomas,
this module is very useful. Many thanks for sharing!
I included it in a program that I'm currently writing, and calling a new instance of the program seemed to work as expected, i.e.
- command line parameters of a new instance are passed to the original instance of the program
- the original instance is activated
- the new instance is terminated
However, I passed relative filenames as command line parameters to my program, and the program should convert them to absolute filenames, with the help of
GetCurrentDirectory(). But that
does not work as expected, because the current directory is not necessarily the same for all instances! As far as I found out, when launching a new instance, its current directory has to be passed to the original instance -- the same way as your code already does with the command line parameters. Here is your code with my additions -- maybe it can be improved:
Code: Select all
;======================================================================
; Module: OnlyOne.pbi
;
; Author: Thomas (ts-soft) Schulz
; Date: Aug 13, 2015
; Version: 1.2a
; (handling of current directory added by Little John;
; tested on Windows 10)
; Target Compiler: PureBasic 5.2+
; Target OS: All
; License: Free, unrestricted, no warranty whatsoever
; Use at your own risk
; URL: http://www.purebasic.fr/english/viewtopic.php?p=468905#p468905
;======================================================================
DeclareModule OnlyOne
EnableExplicit
Declare.i InitOne(wID, ; ID of the main window.
OnlyOneName.s, ; Unique name for Lockfile.
CustomEvent = #PB_Event_FirstCustomValue, ; User-defined event in which the parameters are processed.
TimerID = 1, ; TimerID to use.
TimeOut = 2000) ; Interval in ms, to check the passed parameter queries.
Declare.i ReleaseOne() ; Delete LockFile and removes Timer.
Declare.s GetCurDir()
Declare.s GetParameters() ; The parameter string, separated with #LF$
EndDeclareModule
Module OnlyOne
Global.i Event, win, timer
Global.s LockFile, Paras
Procedure TimerCB()
Static oldtime = 0
If oldtime = 0 : oldtime = Date() : EndIf
Protected FF, time
If FileSize(LockFile) > 0
FF = ReadFile(#PB_Any, LockFile)
If FF
Paras = ""
While Not Eof(FF)
Paras + ReadString(FF) + #LF$
Wend
CloseFile(FF)
FF = CreateFile(#PB_Any, LockFile)
If FF
CloseFile(FF)
EndIf
PostEvent(Event)
EndIf
CompilerSelect #PB_Compiler_OS
CompilerCase #PB_OS_Windows
CompilerDefault
Else
time = AddDate(oldtime, #PB_Date_Minute, 3)
If time < Date()
oldtime = Date()
SetFileDate(LockFile, #PB_Date_Modified, Date())
EndIf
CompilerEndSelect
EndIf
EndProcedure
Procedure.i ReleaseOne()
RemoveWindowTimer(win, timer)
UnbindEvent(#PB_Event_Timer, @TimerCB(), win, timer)
ProcedureReturn DeleteFile(LockFile)
EndProcedure
Procedure.s GetCurDir()
Protected f.i
f = FindString(Paras, #LF$)
ProcedureReturn Left(Paras, f-1)
EndProcedure
Procedure.s GetParameters()
Protected f.i
f = FindString(Paras, #LF$)
ProcedureReturn Mid(Paras, f+1)
EndProcedure
Procedure InitOne(wID, OnlyOneName.s, CustomEvent = #PB_Event_FirstCustomValue, TimerID = 1, TimeOut = 2000)
Protected.i FF, i, j, time, result = #False
If Not IsWindow(wID)
Debug "You have to open a window, before you call this function!"
ProcedureReturn #False
EndIf
win = wID
timer = TimerID
Event = CustomEvent
LockFile = GetTemporaryDirectory() + OnlyOneName
CompilerSelect #PB_Compiler_OS
CompilerCase #PB_OS_Windows
Protected Mutex = CreateMutex_(0, 0, OnlyOneName)
If GetLastError_() = #ERROR_ALREADY_EXISTS
ReleaseMutex_(Mutex)
CloseHandle_(Mutex)
Else
DeleteFile(LockFile)
EndIf
CompilerDefault
time = AddDate(GetFileDate(LockFile, #PB_Date_Modified), #PB_Date_Minute, 5)
If time < Date()
DeleteFile(LockFile)
EndIf
CompilerEndSelect
If FileSize(LockFile) = -1
FF = CreateFile(#PB_Any, LockFile)
If FF
CloseFile(FF)
AddWindowTimer(wID, TimerID, TimeOut)
BindEvent(#PB_Event_Timer, @TimerCB(), wID, TimerID)
Paras = ""
j = CountProgramParameters()
For i = 0 To j
Paras + ProgramParameter(i) + #LF$
Next
Paras = GetCurrentDirectory() + #LF$ +
Left(Paras, Len(Paras) - 1)
PostEvent(Event)
HideWindow(wID, #False)
result = #True
EndIf
Else
FF = OpenFile(#PB_Any, LockFile, #PB_File_Append)
If FF
Paras = ""
j = CountProgramParameters()
For i = 1 To j
Paras + ProgramParameter(i-1) + #LF$
Next
Paras = GetCurrentDirectory() + #LF$ +
Left(Paras, Len(Paras) - 1)
WriteStringN(FF, Paras)
CloseFile(FF)
EndIf
End
EndIf
ProcedureReturn result
EndProcedure
EndModule
CompilerIf #PB_Compiler_IsMainFile
EnableExplicit
Enumeration #PB_Event_FirstCustomValue
#Event_NewParams
EndEnumeration
OpenWindow(0, #PB_Ignore, #PB_Ignore, 640, 480, "Test", #PB_Window_MinimizeGadget|#PB_Window_Invisible)
ListViewGadget(0, 10, 10, WindowWidth(0) - 20, WindowHeight(0) - 20)
OnlyOne::InitOne(0, "Example_Application", #Event_NewParams)
Define i, j, paras.s
Repeat
Select WaitWindowEvent()
Case #PB_Event_CloseWindow
OnlyOne::ReleaseOne()
Break
Case #Event_NewParams
SetActiveWindow(0)
CompilerIf #PB_Compiler_OS = #PB_OS_Windows
ShowWindow_(WindowID(0), #SW_RESTORE)
SetForegroundWindow_(WindowID(0))
CompilerEndIf
AddGadgetItem(0, -1, OnlyOne::GetCurDir())
paras = OnlyOne::GetParameters()
j = CountString(paras, #LF$)
For i = 1 To j
AddGadgetItem(0, -1, StringField(paras, i, #LF$))
Next
EndSelect
ForEver
CompilerEndIf