gdk_get_display error

[Stefan Schnell]

Hello community,
I do my first steps in programming with Linux. Now I have a question about the following error:



The program is very small and works on Windows well:

Code: Select all

; Begin-----------------------------------------------------------------

  EnableExplicit
  
  ; Procedure Main------------------------------------------------------
  
    Procedure Main()
    
      Protected desks.b
      Protected i.l
      
      desks = ExamineDesktops()
      
      Debug desks
      
      If desks
      
        For i = 0 To desks - 1

          Debug Str(DesktopWidth(i)) + " X " + Str(DesktopHeight(i))
        
        Next i
      
      EndIf
  
    EndProcedure

  ; Main----------------------------------------------------------------
    CallDebugger
  
    Main()

; End-------------------------------------------------------------------
End

How can I solve this problem? I use OpenSUSE Linux 10.3.
Thanks for tips.
Cheers
Stefan

[bembulak]

You have installed all the needed dependencies correctly?
Suse, hm?
KDE running? Have you installed GTK2.0 and GTK2.0-devel packages, as well as SDL1.2 and SDL1.2-devel packages with all their dependencies?

Basically this should work. I'll test on my machine, as soon, as I did a reboot. We'll know more then...

[bembulak]

Strange.
If I run the following:

Code: Select all

MessageRequester("Desktop Information", "You have"+Str(ExamineDesktops())+" Desktops.")

it works like a charm.

This also works:

Code: Select all

  ExamineDesktops()
  MessageRequester("Display Information", "Name of main desk = "+DesktopName(0))

As soon, as I do a little more, I get the same error.
Examples

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de = ExamineDesktops()
Debug de
; Linker error

Or this:

Code: Select all

ExamineDesktops()

I don't understand. I'm running Version 4.1 "stable" atm.
Don't know, seems like an issue for the "BUG"-Section.

[#NULL]

i got that error once, too.
i remember something like it works if you open a window before. but it's some time ago, i'm not shure. that could also makes sense cause it works with the requester.

[Stefan Schnell]

Hello bembulak and #NULL,
thanks for your answers and tests, I get the same results with the standard examples. The tip from #NULL solve the problem, if I change the code to:

Code: Select all

; Begin-----------------------------------------------------------------

  EnableExplicit
  
  ; Procedure Main------------------------------------------------------
  
    Procedure Main()
    
      Protected desks.b
      Protected i.l
      
      desks = ExamineDesktops()
      
      Debug desks
      
      If desks
      
        For i = 0 To desks - 1

          Debug Str(DesktopWidth(i)) + " X " + Str(DesktopHeight(i))
        
        Next i
      
      EndIf
  
    EndProcedure

  ; Main----------------------------------------------------------------
    CallDebugger
  
    If OpenWindow(0, 0, 0, 320, 240, "Test", #PB_Window_Invisible)
      Main()
    EndIf

; End-------------------------------------------------------------------
End

it works well. I think as workaround it is okay. I mean it is worth for a message in the bug section, as bembulak write.
Cheers
Stefan

[bembulak]

OK, opening a window before helps. Good to know. This should be in the HELP!
That you'll need a window before, makes sense because:
it could be, one is running a different windowmanager (KDE, ion, blackbox, openbox [like i do], xfwm,...). How should GTK know about your resolution and windowmanager-settings? It simply can't. So it has to wait for a window with GTK-widgets (the main-frame client area) to get advise from the window manager to appear
- on which desktop
- with which resolution
- with which depth.

Makes sense. Not really a bug, but worth a note to the developers for improving the help.

[walker]

Well.. thats only partly true.... you do not need a Window... but you have to call gtk_init_(0,0) and it will work as expected (if opening a Window the gtk_init_() call is done by PB automatically ... but not by other commands as ExamineDesktops() which need the gtk-libs too)

[Stefan Schnell]

Hello walker,
thanks for your tip, it is great. I use now gtk_init_check_(0, 0), as the alternative to gtk_init_(0, 0).
Cheers
Stefan