[Lazarus] fpGUIx

[Henry Vermaak]

On 12/01/11 15:48, michael.vancanneyt at wisa.be wrote:
>
>
> On Wed, 12 Jan 2011, Graeme Geldenhuys wrote:
>
>> Op 2011-01-12 17:13, Michael Schnell het geskryf:
>>>
>>> TThread.Synchronize seems to work fine with fpGUI, but with gtk2 I only
>>> see events when I (e.g.) move the move around on Form.
>>
>>
>> @Michael van Canneyt
>> Now I don't feel so bad. ;-)
>
> Yes, I thought this would cheer you up :-)
>
> I suspect the GTK2 issue has to do with the changed glib main loop
> behaviour.
> It also messes up D-BUS stuff, but I'm still trying to debug that one; I
> need to recompile the LCL each time with a different define
> (USE_GTK_MAIN_OLD_ITERATION)
> to compare main loops :/
>
> Seems like TThread.Synchronize should wake up the GTK main loop.
> The WakeMainThread handler is set for this to happen, but somehow nothing
> happens.

The following code in gtk2winapi.inc wakes up the main loop when a 
message is posted from a different thread (needs -dusecthreads):

   {$IFNDEF USE_GTK_MAIN_OLD_ITERATION}
   if GetCurrentThreadId <> MainThreadID then
   begin
     // old glib versions needs another way to wake up.
     if (glib_major_version = 2) and
       (glib_minor_version < 24) and (FMainPoll <> nil) then
       FMainPoll^.revents := 1;
     g_main_context_wakeup(g_main_context_default);
   end;
   {$ENDIF}

This seems to do the right thing for me when doing a postmessage from an 
external thread.

The main loop should be woken up like this after QueueAsyncCall, too, imo.

Henry