Process Doesn't Stop on "X"

[Gary Beene]

When I run this code and then "X" out of it, the process doesn't go away. I have to open Window Task Manager to stop it.

Function PBMain () As Long
  Local hWin As Dword
  Graphic Window "Box", 300, 300, 130, 130 To hWin
  While 1
  Wend
End Function

Is is supposed to work that way?

[Michael Mattias]

>Is is supposed to work that way?
Well...

 While 1
 Wend

.. usually does not do a whole lot until one does not equal zero. And as a bonus, it is context-agnostic.

Maybe something like

 WHILE ISWIN (hWin) 
 WEND

.. would exit the endless loop when 'hWin' is destroyed and no longer passes the 'smell test' as a valid window.



MCM

[Gary Beene]

Hmm... same thing here. "X" closes the window but not the process.

Function PBMain () As Long
  Local hWin As Dword, i As Long, j As Long
  Graphic Window "Box", 300, 300, 130, 130 To hWin
  For i = 1 To 1000000
     For j = 1 To 1000000
        '
     Next j
  Next i
End Function

MCM, I guess I was expecting the loops to be exited when the "X" was pressed.

Any place you've seen at MSDN that might discuss this?

[Paul Dixon]

Gary,
the code that looks after the window is written by you if you use SDK programming and you'd then trap the appropriate message in the message loop and flag that your program loop should quit.
For DDT programming, as in this case, the compiler will generate the code to do the basic maintenance of the graphic window and you'd need to intercept messages by subclassing the window to see if the window has been closed.
I'd think it's easier, in this case, to just check if the window still exists unless you need to intercept other messages as well.

Paul

[Mike Doty]

Thanks for the info, though not using the feature right now.

FUNCTION PBMAIN () AS LONG
  LOCAL hWin AS DWORD
  GRAPHIC WINDOW "Box", 300, 300, 130, 130 TO hWin
  GRAPHIC ATTACH hWin, 0
  DO
    SLEEP 1000
    GRAPHIC GET CLIENT TO ncWidth!, ncHeight!
    IF ncWidth! = 0 THEN EXIT DO
    BEEP
  LOOP
END FUNCTION

[Dave Biggs]

Gary,

Think of the Graphic Window as a Modeless Dialog that your program (Function PBMain) has created.
Even if it is closed your program will continue to run until it's natural end - by reaching the End Function statement.

[Michael Mattias]

>MCM, I guess I was expecting the loops to be exited when the "X" was pressed.

Huh? Why would it do that?

How then could you EVER create a program which gets input from a GRAPHIC Window, then dismisses the window and goes on to "do something" with that input?

I mean, we've all written a loop like that at one time or another. And I will bet a lot money we've all had exactly the same reaction, too:

MCM

[Manuel Valdes]

Gary:

This subject was posted some weeks ago. I suggested to use the Device Context (DC) in every nested loop to enable the programm to detect whether the graphic window was closed. Even though was deemed ugly, it works.

Regards,

 
GLOBAL hdcon AS LONG
 
Function PBMain () As Long
  Local hWin as Dword
Graphic Window "Box", 300, 300, 130, 130 To hWin
  While 1
    GRAPHIC GET DC TO hdcon
    IF hdcon = 0 THEN EXIT LOOP
  Wend
End Function

[Gary Beene]

Thanks everyone,

I guess I was guilty of a "Window-centric" attitude - when the last window is destroyed, the program is over and the compiler was supposed to add code to shut down the process.

But that's not the case and not even desired since many apps don't even need/want a window.

[Michael Mattias]

guess I was guilty of a "Window-centric" attitude - when the last window is destroyed, the program is over ...

Not true, even if you are thinking "window-centric."

and the compiler was supposed to add code to shut down the process.

Oh, but it does add such code.... when you reach the logical end of WinMain() it adds ExitProcess().

MCM