SHELL statement

[Lance Edmonds]

Best to ask Microsoft why this works when the EndDialog() API says it should not...



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Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Semen Matusovski]

Originally posted by Lance Edmonds:
DIALOG END, like EndDialog(), should *ONLY* be used in the dialog box procedure for the target dialog. Neither of your examples obey this rule.
See EndDialog() in WIN32.HLP for more information.

Lance --
According your interpretation a code below should not work, but it works.

   #Compile Exe
   #Register None
   #Dim All
   #Include "WIN32API.INC"

   Global hDlg As Long, hDlg1 As Long
   
   CallBack Function DlgProc1
      If (CbMsg = %WM_COMMAND) And (CbCtl = 101) Then Dialog End hDlg
   End Function

   CallBack Function DlgProc
      If CbMsg = %WM_DESTROY Then MsgBox "hDlg has been destroyed"
   End Function

   
   Function PbMain
      Dialog New 0, "hDlg", 100, 100, 100, 100, %WS_CAPTION To hdlg
      Dialog New 0, "hDlg1", 300, 300, 100, 15, %WS_CAPTION To hdlg1
      Control Add Button, hDlg1, 101, "Stop hDlg", 0, 0, 100, 15
      Dialog Show Modeless hDlg1 Call DlgProc1
      Dialog Show Modal hDlg Call DlgProc
   End Function

Note, EndDialog has hDlg as a first parameter.
Results of EndDialog, as I understand, are equal to SDK WM_CLOSE + PostQuitMessage.

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E-MAIL: [email protected]

[Branko Bedenik]

Lance,
As I don't know how to include file into this reply
i've sent you sample code by Email

Branko

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[Lance Edmonds]

Oh, I forgot to mention that the next update to the documentation for DIALOG END will include these notes!


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Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Lance Edmonds]

DIALOG END is a wrapper for EndDialog(), so the same basic rules apply to both the statement and the API call.

Regarding TCP_NOTIFY, I don't have any documentation to hand (I'm not at my Dev PC), but if you post a new query to the Internet Programming forum (so we don't get too far off-topic here!), I'll see what I can dig up for you.

getting back to the original topic... Branko needs to post some code or email it to Tech Support... the ball is in his court now!




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Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Fred Oxenby]

I am not sure that I understand what you are saying, Lance
Is 'Dialog End' a statment that has to be executed inside
a Callback Function for the target Dialog?
Is that a new addition to PB documentation for Dialog End?
---
I am asking because you frequently advice us to look up API-call in
MSDN.Am I supposed to know that the documentation for Dialog End is to be found
in MSDN under EndDialog?
---
This is perhaps unrelated,
But, where do I find documentation on TCP NOTIFY? I understand what wMsg will contain.
what about wParam and lParam what will TCP NOTIFY put in there when the handled event occur?
This is an internal Powerbasic statment, but as I cannot find any
information in PB-documentation, I have searched MSDN but only
come up with one unrelated hit.





------------------
Fred
mailto:[email protected][email protected]</A>
http://www.oxenby.se

[Steve Hutchesson]

Branko,

What we need is the basics of how you have created the called
applications. Depending on if you have used CreateWindowEx() for a normal
window style app, an API style MODAL or MODELESS dialog or if you have
used the PowerBASIC DDT to create the called apps, there are different
methods required to properly close each type.

The function call,

SendMessage hWnd,%WM_SYSCOMMAND,%SC_CLOSE,ByVal %NULL

will close most things but to properly close your application so that control
returns to the caller from the SHELL statement, each method is specific.

All you need to do is paste in the code that creates the called application,
it is a lot easier to read in the forum if you use the notation enclosed in
square brackets,

"code" on the line before the code and

"/code" on the next line after the code.

Once we know what the app type is, there are many people here who can help you.

Regards,

[email protected]


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[Lance Edmonds]

DIALOG END, like EndDialog(), should *ONLY* be used in the dialog box procedure for the target dialog. Neither of your examples obey this rule.

See EndDialog() in WIN32.HLP for more information.



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Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Semen Matusovski]

Lance --
Well ...
Situation #1 - Thread.

   #Compile Exe
   #Register None
   #Dim All
   #Include "win32api.inc"

   Global hDlg2 As Long
   
   Function Thread1(ByVal hDlg&)As Long
      Dialog New hDlg&, "TestB", 120,100,100,100 To hDlg2
      Dialog Show Modal hDlg2
      MsgBox "Finished"
   End Function
  
   CallBack Function Btn1
      PostMessage hDlg2, %WM_SYSCOMMAND, %SC_CLOSE, 0
   End Function

   CallBack Function Btn2
      SendMessage hDlg2, %WM_SYSCOMMAND, %SC_CLOSE, 0
   End Function

   CallBack Function Btn3
      Dialog End hDlg2
   End Function

   Function PbMain
      Local hDlg As Long, t As Long
      Dialog New 0, "TestA", , , 100, 80, %WS_CAPTION Or %WS_SYSMENU To hDlg
      Control Add Button, hDlg,101, "PostMessage (+)", 10, 10, 80, 15 Call BTN1
      Control Add Button, hDlg,102, "SendMessage (-)", 10, 30, 80, 15 Call BTN2
      Control Add Button, hDlg,103, "Dialog End  (-)", 10, 50, 80, 15 Call BTN3
      Thread Create Thread1(0) To t
      Thread Close t To t
      Dialog Show Modal hDlg
   End Function

Sample #2 - Shell

B.Bas (compile it)

   #Compile Exe
   #Register None
   #Dim All
   #Include "win32api.inc"

   Function PbMain
      Local hDlg As Long
      Dialog New 0, "TestB", , , 100, 80, %WS_CAPTION Or %WS_SYSMENU To hDlg
      Dialog Show Modal hDlg
      MsgBox "Finished"
   End Function

Program A.Bas (Shells B)

   #Compile Exe
   #Register None
   #Dim All
   #Include "win32api.inc"

   CallBack Function Btn1
      PostMessage FindWindow("", "TestB"), %WM_SYSCOMMAND, %SC_CLOSE, 0
   End Function

   CallBack Function Btn2
      SendMessage FindWindow("", "TestB"), %WM_SYSCOMMAND, %SC_CLOSE, 0
   End Function

   CallBack Function Btn3
      Dialog End FindWindow("", "TestB")
   End Function

   Function PbMain
      Local hDlg As Long, t As Long
      Dialog New 0, "TestA", 0, 0, 100, 80, %WS_CAPTION Or %WS_SYSMENU To hDlg
      Control Add Button, hDlg,101, "PostMessage (+)", 10, 10, 80, 15 Call BTN1
      Control Add Button, hDlg,102, "SendMessage (-)", 10, 30, 80, 15 Call BTN2
      Control Add Button, hDlg,103, "Dialog End  (-)", 10, 50, 80, 15 Call BTN3
      t = Shell("b.Exe")
      Dialog Show Modal hDlg
   End Function

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E-MAIL: [email protected]

[Branko Bedenik]

Lance

I would like to send you sample Code
but don't know how to include it from file into this Reply!!!

sorry
Branko

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[Lance Edmonds]

Really? How about telling us about some of them, Semen!

In every single case I've seen, the problem is with the implementation of the dialog and/or message pump, not DIALOG END.

Also, how does SendMessage() figure in DIALOG END?

...?


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Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Semen Matusovski]

I know enough situations, when Dialog End (SendMessage) doesn't work.
That's why I use PostMessage.


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E-MAIL: [email protected]

[Steve Hutchesson]

Branko,

I use the SHELL statement with installations that work fine on everything
from early win95 to winME with no problems at all and some of the EXE
files being run are in megabytes so it is not a problem with either the
SHELL statement or the application size, it is still a problem of the
application not closing properly under some conditions.

Because SHELL as a statement is synchronous, you will continue to get this
effect until you work out how to close the second application cleanly.

Just post the basic logic of your application so we know what it is and the
rest should be reasonably straight forward.

Regards,

[email protected]

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[Lance Edmonds]

Possible? Yes (anything is possible!). Likely? I don't *believe* so.

I would suspect that there is still some error condition in your program that you are not checking for, or that your message loop is still not closing. While you use DIALOG END, you have not given us enough information as to whether your dialog is modal or modeless, and whether you have checked that the message pump is actually terminating.

Really, you are going to have to show us some source code to provide more specific help. Sorry!


------------------
Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Branko Bedenik]

Lance and Steve

well, i've closed dialog in ProgramB
DIALOG END hInfoOkno
and closed app by
SendMessage hWndMain, %WM_SYSCOMMAND,%SC_CLOSE, ByVal %NULL

It seems to me that problem lies in the size of the problem.
If (ProgramB solves the equations, dimensioning of matrices depends on
the size of the problem) the number of equations
is moderate, then return controls to the calling program,
but if size increases i run into problems,
though ProgramB DOES NOT complain at all!
Is it possible?
I'm using W2000 Pro OS.

Thanks
Branko


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[Steve Hutchesson]

Branko,

Just give this a whirl to terminate the second app cleanly,

SendMessage hWnd,%WM_SYSCOMMAND,%SC_CLOSE,ByVal %NULL

Sending this message is like pressing the system close button
on the title bar.

Regards,

[email protected]

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[Lance Edmonds]

It actually sounds most likely that ProgramB is not closing properly (even if the window is closed, the app's message pump is probably still running).

As a result, the main application actually never returns from the SHELL statement that launched ProgramB, because ProgramB has not actually finished running!

So, does DestroyWindow() close it's own window, or are you trying to do this from/to another app? Also, under what conditions are you using DestroyWindow() ? How is the message pump constructed in ProgramB?

With a "standard" SDK-style app, you would close a window by sending %WM_CLOSE. This results in a %WM_DESTROY message, and in response to this message, your app should call PostQuitMessage() to ensure that the message pump is terminated.

However, with dialog based app's, you need to use EndDialog() or DIALOG END (DDT) instead of DestroyWindow(). If the dialog is modeless, you still need to signal the message pump to close at the right time. The best method for this will depend on what your code is doing, but generally, some kind of flag that indicates that the target window has been destroyed will work. For DDT dialog suggestions, see DIALOG DOEVENTS in the help file.

So, in summary, your problem is most likely to be in the design/implementation of ProgramB, and not the SHELL statement at all.

Post the code to ProgramB and lets see what we can do to help.


------------------
Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Branko Bedenik]

I'm afraid it is not so simple.

In ProgramB I destroy application by "DestroyWindow hWnd",
if it is run standalone it closes program
properly, but if it is run from Calling program using SHELL
it doesn't , calling program just hangs.

Any other solutions?

Regards
Branko

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[Steve Hutchesson]

Branko,

SHELL is a very useful statement in that it runs another program
synchronously where the SHELL() function runs another program
asynchronously.

The catch is with the SHELL statement is that it does not return control
back to your program until the SHELLed program is closed.

I would be inclined to make sure each program is closed properely before
you call the next one otherwise control will not be returned to your
program.

Regards,

[email protected]

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[Branko Bedenik]

Hi

Using PB/DLL 6 compiler I SHELL two different EXE programs:

...Code
SHELL "ProgramA testA"
...Code
SHELL "ProgramB testB"
...Code

If I run ProgramA first and then ProgramB, the control
after execution of ProgramB does not return to the program,
the program has to be restarted.
But if I run ProgramA or ProgramB only control
returns to the program normally.
Any idea why it hangs?

Branko



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