Re: Can GTK run without a C main function?

[Michael Torrie <torriem gmail com>]

On 03/23/2012 10:23 AM, Patrick wrote:
> Hi Everyone
> 
> Please forgive this strange post, I am not a professional programmer but 
> I am trying something a bit difficult.
> 
> I like Lua but I have fallen in love with Ada now. 

Looking at Ada Lovelace's wikipedia page, she is portrayed as a fairly
attractive woman, so I don't blame you. :)

> Lua's library support
> is not great but the language really shines when used with C libraries. 
> I would like to use Ada in a similar way and ignore all the Ada 
> libraries, including the GTK binding.
> 
> I am presently trying to compile a mixed c ada application. The program 
> calls C GTK in a non main c function. The main function is on the Ada side.
> 
> Is this permissible? Does GTK depend on a C entry point?

So far as I know, gtk wants to be initialized with gtk_init().  Then you
have to start up the GTK main loop with gtk_main().  You can do this
from anywhere, not just main.  Unfortunately, calling gtk_main does not
return until a call to gtk_quit().  So you could say that gtk_main is
the C entry point.

If you are okay with GTK being in control, and calling back into your
ada functions, then it should work fine.  And really in event-driven
programming, you react to events anyway.  You don't program procedurally.

If you have an Ada loop you have to run, either to poll something or to
do a long-running calculation or process, you could do it in another
thread I, and call g_idle_add to do things in the main GTK GUI thread.