GTK基础知识：从资源中学习

Question

我是编程Gtk gnome linux C应用程序的新手，我正在尝试从一些源代码reagind和在线gnome文档中学习，但我不能这样做，因为这在我看来非常糟糕和糟糕。我有一个问题需要理解以下来源：在创建GApplication类型的GObject之后，这个main函数如何调用程序的其他部分？ （这是来自gedit源码）我了解到GApplication不包含任何指向某些代码的指针。

/*
 * gedit.c
 * This file is part of gedit
 *
 * Copyright (C) 2005 - Paolo Maggi
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "gedit-app.h"
#ifdef OS_OSX
#include "gedit-app-osx.h"
#else
#ifdef G_OS_WIN32
#include "gedit-app-win32.h"
#else
#include "gedit-app-x11.h"
#endif
#endif

#include <glib.h>
#include <locale.h>
#include <libintl.h>

#include "gedit-dirs.h"
#include "gedit-debug.h"

#ifdef G_OS_WIN32
#include <gmodule.h>
static GModule *libgedit_dll = NULL;

/* This code must live in gedit.exe, not in libgedit.dll, since the whole
 * point is to find and load libgedit.dll.
 */
static gboolean
gedit_w32_load_private_dll (void)
{
    gchar *dllpath;
    gchar *prefix;

    prefix = g_win32_get_package_installation_directory_of_module (NULL);

    if (prefix != NULL)
    {
        /* Instead of g_module_open () it may be possible to do any of the
         * following:
         * A) Change PATH to "${dllpath}/lib/gedit;$PATH"
         * B) Call SetDllDirectory ("${dllpath}/lib/gedit")
         * C) Call AddDllDirectory ("${dllpath}/lib/gedit")
         * But since we only have one library, and its name is known, may as well
         * use gmodule.
         */
        dllpath = g_build_filename (prefix, "lib", "gedit", "libgedit.dll", NULL);
        g_free (prefix);

        libgedit_dll = g_module_open (dllpath, 0);
        if (libgedit_dll == NULL)
        {
            g_printerr ("Failed to load '%s': %s\n",
                        dllpath, g_module_error ());
        }

        g_free (dllpath);
    }

    if (libgedit_dll == NULL)
    {
        libgedit_dll = g_module_open ("libgedit.dll", 0);
        if (libgedit_dll == NULL)
        {
            g_printerr ("Failed to load 'libgedit.dll': %s\n",
                        g_module_error ());
        }
    }

    return (libgedit_dll != NULL);
}

static void
gedit_w32_unload_private_dll (void)
{
    if (libgedit_dll)
    {
        g_module_close (libgedit_dll);
        libgedit_dll = NULL;
    }
}
#endif

int
main (int argc, char *argv[])
{
    GType type;
    GeditApp *app;
    gint status;
    const gchar *dir;

#ifdef OS_OSX
    type = GEDIT_TYPE_APP_OSX;
#else
#ifdef G_OS_WIN32
    if (!gedit_w32_load_private_dll ())
    {
        return 1;
    }

    type = GEDIT_TYPE_APP_WIN32;
#else
    type = GEDIT_TYPE_APP_X11;
#endif
#endif

    /* NOTE: we should not make any calls to the gedit api before the
     * private library is loaded */
    gedit_dirs_init ();

    /* Setup locale/gettext */
    setlocale (LC_ALL, "");

    dir = gedit_dirs_get_gedit_locale_dir ();
    bindtextdomain (GETTEXT_PACKAGE, dir);

    bind_textdomain_codeset (GETTEXT_PACKAGE, "UTF-8");
    textdomain (GETTEXT_PACKAGE);

    app = g_object_new (type,
                        "application-id", "org.gnome.gedit",
                        "flags", G_APPLICATION_HANDLES_COMMAND_LINE | G_APPLICATION_HANDLES_OPEN,
                        NULL);

    status = g_application_run (G_APPLICATION (app), argc, argv);

    /* Break reference cycles caused by the PeasExtensionSet
     * for GeditAppActivatable which holds a ref on the GeditApp
     */
    g_object_run_dispose (G_OBJECT (app));

    g_object_add_weak_pointer (G_OBJECT (app), (gpointer *) &app);
    g_object_unref (app);

    if (app != NULL)
    {
        gedit_debug_message (DEBUG_APP, "Leaking with %i refs",
                             G_OBJECT (app)->ref_count);
    }

#ifdef G_OS_WIN32
    gedit_w32_unload_private_dll ();
#endif

    return status;
}

/* ex:set ts=8 noet: */