Re: [gtk-list] Re: Newbie Gtk+ questions...

["Larry 'Daffy' Daffner" <vizzie mail airmail net>]

>>>>> "OT" == Owen Taylor <owt1@cornell.edu> writes:

[ integer valued scale ]
  OT> If you want a scale widget that actually moves in integer
  OT> increments, then you are out of luck, unless you write your
  OT> own. Otherwise, just use

  OT>   gtk_scale_set_digits (GTK_SCALE(my_scale), 0);

That will do the trick. It will be easy enough to convert the value to
an int myself when I get it back :)

  >> 3) I have an idle procedure which ends up taking about
  >> 500ms. This makes interactive performance *really* bad :). From
  >> UTS,L!

  OT> <curious> what's that? </curious>

UTS,L! = Use The Source, Luke! (IE, digging through the gtk code :)
If you're talking about the idle procedure, it's a procedure which
reads an image from the quickcam using libqcam (~350ms for a
320x240x6bpp gray image), and thunking it into a gtkimage and writing
it to the screen (~120ms or so).

  >> it appears that splitting it up into 2 procedures will still call
  >> both procedures between event checks, no matter what.

  OT> Not " matter what". One thing you can do which will work is to
  OT> set up the second half as a one-shot idle handler at a higher
  OT> priority than the first half. (You'll need the CVS gtk for this,
  OT> which has gtk_idle_add_priority(), or it will appear in the next
  OT> release)

Sounds confusing.. I'll just go with...

  >> Can I call gtk_main_iteration_do() in the middle of my idle
  >> function and have it process events correctly, or am I basically
  >> taking my chances if I do that?

  OT> Just calling gtk_main_iteration_do() is taking your
  OT> chances. (The non-block isn't currently working) But doing:

  OT>   while (gtk_events_pending()) gtk_main_iteration();

This here.. That seems to work better (though that 350ms grab is still
a hit - I may need to bite the bullet and do the qcam stuff myself :()
and is simple enough for a beginner like me to understand. :)

  OT> will work safely. Though, if you do this, idle redraws may not
  OT> work correctly. [ I haven't tested it out, but it strikes me
  OT> that this may be the case. Maybe gtk_events_pending() should
  OT> count idle handlers above some priority as pending events? ]

Idle redraws? What's that? Should I be concerned?

  >> 4) What's the correct syntax for using the space bar as a menu
  >> accelerator?

  OT> I think " " should work. (I, unfortunately, won't show up on the
  OT> menu, though)

Duuuh. That works. :) Here I was thinking it was something hard :)

Thanks for all the help :)

-Larry

-- 
  Larry Daffner        |  Linux: Unleash the workstation in your PC!
  vizzie@airmail.net / http://web2.airmail.net/vizzie/
There is nothing so terrifying as ignorance in action. 
	-- Col Jeff Cooper