XForms: fl_addto_selected_xevent flakey on Linux w/XCreateWindow?

From: Lawrence M. Lifshitz (Lawrence.Lifshitz@umassmed.edu)
Date: Thu Apr 26 2001 - 13:20:24 EDT

  • Next message: Lawrence M. Lifshitz: "Re: XForms: fl_addto_selected_xevent flakey on Linux w/XCreateWindow? correction"

    # To subscribers of the xforms list from "Lawrence M. Lifshitz" <Lawrence.Lifshitz@umassmed.edu> :

      I have a large application using xforms.89 which works fine on
    an SGI O2 running 6.5 IRIX. In it I use XCreateWindow to create a
    render window and use xforms to create a bunch of widgets. The
    widgets use callbacks. I then loop
        {if (fl_check_forms() == FL_EVENT)
             switch (ev.type) {...}
        } while (fl_XEventsQueued(QueuedAfterFlush));

    My problem is that this does not work on my RedHat 7.0 Linux PC.

    The xevents never seem to be returned by fl_check_forms.
    I tried adding an explicit call to fl_addto_selected_xevent(winid,
    (I did not use this at all on the SGI).
    This caused my render window to hang after one redraw and
    the messages:
      PutBackEvent Event (6,w=0x1c00013,s=4124) MotionNotify Mode Normal
      In PutBackEvent [events.c 334] Q overflow
    to appear repeatedly when my mouse moved in the render window
    (the number 4124 increments by 10 each new error message).

    I thought maybe I was generating too many events so I explicitly
    added PointerMotionHintMask to my xvents mask (which I believe should
    only give an event once while the mouse moves unless a button state
    changes), but that made no difference.

    I don't use the forms call to create my render windows because this is a
    legacy program originally created before OpenGL, so it was set up to
    handle all
    its own render windows.

    1). Why does it work ok on the SGI but not RedHat 7.0?
    2). Should I be able to call fl_addto_selected_xevent with an id
    returned by
        XCreateWindow and expect it to work?
    3). Is the Q overflow message coming from X11? or from xforms?
    4). Is there any way to still use XCreateWindow and retrieve xevents
    from it?

    by the way, other than this, my program (which is >100,000 lines of code
    hundreds of xforms widgets)runs great on the Linux box (with nvidia
    geforce2 card)!
    thanks for any help!

    Lawrence M. Lifshitz, Ph.D.	    
    Biomedical Imaging Group - University of Massachusetts Medical School
    Phone: (508) 856-3392  	   email:    Lawrence.Lifshitz@umassmed.edu
    FAX: (508) 856-1840	   web:	     http://invitro.umassmed.edu/~lml
    To unsubscribe, send the message "unsubscribe" to
    xforms-request@bob.usuhs.mil   or see
    XForms Home Page: http://world.std.com/~xforms
    List Archive: http://bob.usuhs.mil/mailserv/list-archives/

    This archive was generated by hypermail 2b29 : Thu Apr 26 2001 - 13:30:56 EDT