gtkapplication.c

/*
 * Copyright © 2010 Codethink Limited
 * Copyright © 2013 Canonical Limited
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the licence, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library. If not, see <http://www.gnu.org/licenses/>.
 *
 * Author: Ryan Lortie <desrt@desrt.ca>
 */

#include "config.h"

#include "gtkapplication.h"
#include "gdkprivate.h"

#ifdef G_OS_UNIX
#include <gio/gunixfdlist.h>
#endif

#include <stdlib.h>

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#include "gdk/gdk-private.h"

#include "gtkapplicationprivate.h"
#include "gtkclipboardprivate.h"
#include "gtkmarshalers.h"
#include "gtkmain.h"
#include "gtkrecentmanager.h"
#include "gtkaccelmapprivate.h"
#include "gtkicontheme.h"
#include "gtkbuilder.h"
#include "gtkshortcutswindow.h"
#include "gtkintl.h"

/* NB: please do not add backend-specific GDK headers here.  This should
 * be abstracted via GtkApplicationImpl.
 */

/**
 * SECTION:gtkapplication
 * @title: GtkApplication
 * @short_description: Application class
 *
 * #GtkApplication is a class that handles many important aspects
 * of a GTK+ application in a convenient fashion, without enforcing
 * a one-size-fits-all application model.
 *
 * Currently, GtkApplication handles GTK+ initialization, application
 * uniqueness, session management, provides some basic scriptability and
 * desktop shell integration by exporting actions and menus and manages a
 * list of toplevel windows whose life-cycle is automatically tied to the
 * life-cycle of your application.
 *
 * While GtkApplication works fine with plain #GtkWindows, it is recommended
 * to use it together with #GtkApplicationWindow.
 *
 * When GDK threads are enabled, GtkApplication will acquire the GDK
 * lock when invoking actions that arrive from other processes.  The GDK
 * lock is not touched for local action invocations.  In order to have
 * actions invoked in a predictable context it is therefore recommended
 * that the GDK lock be held while invoking actions locally with
 * g_action_group_activate_action().  The same applies to actions
 * associated with #GtkApplicationWindow and to the “activate” and
 * “open” #GApplication methods.
 *
 * ## Automatic resources ## {#automatic-resources}
 *
 * #GtkApplication will automatically load menus from the #GtkBuilder
 * resource located at "gtk/menus.ui", relative to the application's
 * resource base path (see g_application_set_resource_base_path()).  The
 * menu with the ID "app-menu" is taken as the application's app menu
 * and the menu with the ID "menubar" is taken as the application's
 * menubar.  Additional menus (most interesting submenus) can be named
 * and accessed via gtk_application_get_menu_by_id() which allows for
 * dynamic population of a part of the menu structure.
 *
 * If the resources "gtk/menus-appmenu.ui" or "gtk/menus-traditional.ui" are
 * present then these files will be used in preference, depending on the value
 * of gtk_application_prefers_app_menu(). If the resource "gtk/menus-common.ui"
 * is present it will be loaded as well. This is useful for storing items that
 * are referenced from both "gtk/menus-appmenu.ui" and
 * "gtk/menus-traditional.ui".
 *
 * It is also possible to provide the menus manually using
 * gtk_application_set_app_menu() and gtk_application_set_menubar().
 *
 * #GtkApplication will also automatically setup an icon search path for
 * the default icon theme by appending "icons" to the resource base
 * path.  This allows your application to easily store its icons as
 * resources.  See gtk_icon_theme_add_resource_path() for more
 * information.
 *
 * If there is a resource located at "gtk/help-overlay.ui" which
 * defines a #GtkShortcutsWindow with ID "help_overlay" then GtkApplication
 * associates an instance of this shortcuts window with each
 * #GtkApplicationWindow and sets up keyboard accelerators (Control-F1
 * and Control-?) to open it. To create a menu item that displays the
 * shortcuts window, associate the item with the action win.show-help-overlay.
 *
 * ## A simple application ## {#gtkapplication}
 *
 * [A simple example](https://git.gnome.org/browse/gtk+/tree/examples/bp/bloatpad.c)
 *
 * GtkApplication optionally registers with a session manager
 * of the users session (if you set the #GtkApplication:register-session
 * property) and offers various functionality related to the session
 * life-cycle.
 *
 * An application can block various ways to end the session with
 * the gtk_application_inhibit() function. Typical use cases for
 * this kind of inhibiting are long-running, uninterruptible operations,
 * such as burning a CD or performing a disk backup. The session
 * manager may not honor the inhibitor, but it can be expected to
 * inform the user about the negative consequences of ending the
 * session while inhibitors are present.
 *
 * ## See Also ## {#seealso}
 * [HowDoI: Using GtkApplication](https://wiki.gnome.org/HowDoI/GtkApplication),
 * [Getting Started with GTK+: Basics](https://developer.gnome.org/gtk3/stable/gtk-getting-started.html#id-1.2.3.3)
 */

enum {
  WINDOW_ADDED,
  WINDOW_REMOVED,
  QUERY_END,
  LAST_SIGNAL
};

static guint gtk_application_signals[LAST_SIGNAL];

enum {
  PROP_ZERO,
  PROP_REGISTER_SESSION,
  PROP_SCREENSAVER_ACTIVE,
  PROP_APP_MENU,
  PROP_MENUBAR,
  PROP_ACTIVE_WINDOW,
  NUM_PROPERTIES
};

static GParamSpec *gtk_application_props[NUM_PROPERTIES];

struct _GtkApplicationPrivate
{
  GtkApplicationImpl *impl;
  GtkApplicationAccels *accels;

  GList *windows;

  GMenuModel      *app_menu;
  GMenuModel      *menubar;
  guint            last_window_id;

  gboolean         register_session;
  gboolean         screensaver_active;
  GtkActionMuxer  *muxer;
  GtkBuilder      *menus_builder;
  gchar           *help_overlay_path;
  guint            profiler_id;
};

G_DEFINE_TYPE_WITH_PRIVATE (GtkApplication, gtk_application, G_TYPE_APPLICATION)

static gboolean
gtk_application_focus_in_event_cb (GtkWindow      *window,
                                   GdkEventFocus  *event,
                                   GtkApplication *application)
{
  GtkApplicationPrivate *priv = application->priv;
  GList *link;

  /* Keep the window list sorted by most-recently-focused. */
  link = g_list_find (priv->windows, window);
  if (link != NULL && link != priv->windows)
    {
      priv->windows = g_list_remove_link (priv->windows, link);
      priv->windows = g_list_concat (link, priv->windows);
    }

  if (application->priv->impl)
    gtk_application_impl_active_window_changed (application->priv->impl, window);

  g_object_notify_by_pspec (G_OBJECT (application), gtk_application_props[PROP_ACTIVE_WINDOW]);

  return GDK_EVENT_PROPAGATE;
}

static void
gtk_application_load_resources (GtkApplication *application)
{
  const gchar *base_path;

  base_path = g_application_get_resource_base_path (G_APPLICATION (application));

  if (base_path == NULL)
    return;

  /* Expand the icon search path */
  {
    GtkIconTheme *default_theme;
    gchar *iconspath;

    default_theme = gtk_icon_theme_get_default ();
    iconspath = g_strconcat (base_path, "/icons/", NULL);
    gtk_icon_theme_add_resource_path (default_theme, iconspath);
    g_free (iconspath);
  }

  /* Load the menus */
  {
    gchar *menuspath;

    /* If the user has given a specific file for the variant of menu
     * that we are looking for, use it with preference.
     */
    if (gtk_application_prefers_app_menu (application))
      menuspath = g_strconcat (base_path, "/gtk/menus-appmenu.ui", NULL);
    else
      menuspath = g_strconcat (base_path, "/gtk/menus-traditional.ui", NULL);

    if (g_resources_get_info (menuspath, G_RESOURCE_LOOKUP_FLAGS_NONE, NULL, NULL, NULL))
      application->priv->menus_builder = gtk_builder_new_from_resource (menuspath);
    g_free (menuspath);

    /* If we didn't get the specific file, fall back. */
    if (application->priv->menus_builder == NULL)
      {
        menuspath = g_strconcat (base_path, "/gtk/menus.ui", NULL);
        if (g_resources_get_info (menuspath, G_RESOURCE_LOOKUP_FLAGS_NONE, NULL, NULL, NULL))
          application->priv->menus_builder = gtk_builder_new_from_resource (menuspath);
        g_free (menuspath);
      }

    /* Always load from -common as well, if we have it */
    menuspath = g_strconcat (base_path, "/gtk/menus-common.ui", NULL);
    if (g_resources_get_info (menuspath, G_RESOURCE_LOOKUP_FLAGS_NONE, NULL, NULL, NULL))
      {
        GError *error = NULL;

        if (application->priv->menus_builder == NULL)
          application->priv->menus_builder = gtk_builder_new ();

        if (!gtk_builder_add_from_resource (application->priv->menus_builder, menuspath, &error))
          g_error ("failed to load menus-common.ui: %s", error->message);
      }
    g_free (menuspath);

    if (application->priv->menus_builder)
      {
        GObject *menu;

        menu = gtk_builder_get_object (application->priv->menus_builder, "app-menu");
        if (menu != NULL && G_IS_MENU_MODEL (menu))
          gtk_application_set_app_menu (application, G_MENU_MODEL (menu));
        menu = gtk_builder_get_object (application->priv->menus_builder, "menubar");
        if (menu != NULL && G_IS_MENU_MODEL (menu))
          gtk_application_set_menubar (application, G_MENU_MODEL (menu));
      }
  }

  /* Help overlay */
  {
    gchar *path;

    path = g_strconcat (base_path, "/gtk/help-overlay.ui", NULL);
    if (g_resources_get_info (path, G_RESOURCE_LOOKUP_FLAGS_NONE, NULL, NULL, NULL))
      {
        const gchar * const accels[] = { "<Primary>F1", "<Primary>question", NULL };

        application->priv->help_overlay_path = path;
        gtk_application_set_accels_for_action (application, "win.show-help-overlay", accels);
      }
    else
      {
        g_free (path);
      }
  }
}


static void
gtk_application_startup (GApplication *g_application)
{
  GtkApplication *application = GTK_APPLICATION (g_application);

  G_APPLICATION_CLASS (gtk_application_parent_class)->startup (g_application);

  gtk_action_muxer_insert (application->priv->muxer, "app", G_ACTION_GROUP (application));

  gtk_init (NULL, NULL);

  application->priv->impl = gtk_application_impl_new (application, gdk_display_get_default ());
  gtk_application_impl_startup (application->priv->impl, application->priv->register_session);

  gtk_application_load_resources (application);
}

static void
gtk_application_shutdown (GApplication *g_application)
{
  GtkApplication *application = GTK_APPLICATION (g_application);

  if (application->priv->impl == NULL)
    return;

  gtk_application_impl_shutdown (application->priv->impl);
  g_clear_object (&application->priv->impl);

  gtk_action_muxer_remove (application->priv->muxer, "app");

  /* Keep this section in sync with gtk_main() */

  /* Try storing all clipboard data we have */
  _gtk_clipboard_store_all ();

  /* Synchronize the recent manager singleton */
  _gtk_recent_manager_sync ();

  G_APPLICATION_CLASS (gtk_application_parent_class)->shutdown (g_application);
}

static gboolean
gtk_application_local_command_line (GApplication   *application,
                                    gchar        ***arguments,
                                    gint           *exit_status)
{
  g_application_add_option_group (application, gtk_get_option_group (FALSE));

  return G_APPLICATION_CLASS (gtk_application_parent_class)->local_command_line (application, arguments, exit_status);
}

static void
gtk_application_add_platform_data (GApplication    *application,
                                   GVariantBuilder *builder)
{
  /* This is slightly evil.
   *
   * We don't have an impl here because we're remote so we can't figure
   * out what to do on a per-display-server basis.
   *
   * So we do all the things... which currently is just one thing.
   */
  const gchar *desktop_startup_id =
    GDK_PRIVATE_CALL (gdk_get_desktop_startup_id) ();
  if (desktop_startup_id)
    g_variant_builder_add (builder, "{sv}", "desktop-startup-id",
                           g_variant_new_string (desktop_startup_id));
}

static void
gtk_application_before_emit (GApplication *g_application,
                             GVariant     *platform_data)
{
  GtkApplication *application = GTK_APPLICATION (g_application);

  gdk_threads_enter ();

  gtk_application_impl_before_emit (application->priv->impl, platform_data);
}

static void
gtk_application_after_emit (GApplication *application,
                            GVariant     *platform_data)
{
  const char *startup_notification_id = NULL;

  g_variant_lookup (platform_data, "desktop-startup-id", "&s", &startup_notification_id);
  if (startup_notification_id)
    {
      GdkDisplay *display;

      display = gdk_display_get_default ();
      if (display)
        gdk_display_notify_startup_complete (display, startup_notification_id);
    }

  gdk_threads_leave ();
}

static void
gtk_application_init (GtkApplication *application)
{
  application->priv = gtk_application_get_instance_private (application);

  application->priv->muxer = gtk_action_muxer_new ();

  application->priv->accels = gtk_application_accels_new ();

  /* getenv now at the latest */
  GDK_PRIVATE_CALL (gdk_get_desktop_startup_id) ();
}

static void
gtk_application_window_added (GtkApplication *application,
                              GtkWindow      *window)
{
  GtkApplicationPrivate *priv = application->priv;

  if (GTK_IS_APPLICATION_WINDOW (window))
    {
      gtk_application_window_set_id (GTK_APPLICATION_WINDOW (window), ++priv->last_window_id);
      if (priv->help_overlay_path)
        {
          GtkBuilder *builder;
          GtkWidget *help_overlay;

          builder = gtk_builder_new_from_resource (priv->help_overlay_path);
          help_overlay = GTK_WIDGET (gtk_builder_get_object (builder, "help_overlay"));
          if (GTK_IS_SHORTCUTS_WINDOW (help_overlay))
            gtk_application_window_set_help_overlay (GTK_APPLICATION_WINDOW (window),
                                                     GTK_SHORTCUTS_WINDOW (help_overlay));
          g_object_unref (builder);
        }
    }

  priv->windows = g_list_prepend (priv->windows, window);
  gtk_window_set_application (window, application);
  g_application_hold (G_APPLICATION (application));

  g_signal_connect (window, "focus-in-event",
                    G_CALLBACK (gtk_application_focus_in_event_cb),
                    application);

  gtk_application_impl_window_added (priv->impl, window);

  gtk_application_impl_active_window_changed (priv->impl, window);

  g_object_notify_by_pspec (G_OBJECT (application), gtk_application_props[PROP_ACTIVE_WINDOW]);
}

static void
gtk_application_window_removed (GtkApplication *application,
                                GtkWindow      *window)
{
  GtkApplicationPrivate *priv = application->priv;
  gpointer old_active;

  old_active = priv->windows;

  if (priv->impl)
    gtk_application_impl_window_removed (priv->impl, window);

  g_signal_handlers_disconnect_by_func (window,
                                        gtk_application_focus_in_event_cb,
                                        application);

  g_application_release (G_APPLICATION (application));
  priv->windows = g_list_remove (priv->windows, window);
  gtk_window_set_application (window, NULL);

  if (priv->windows != old_active && priv->impl)
    {
      gtk_application_impl_active_window_changed (priv->impl, priv->windows ? priv->windows->data : NULL);
      g_object_notify_by_pspec (G_OBJECT (application), gtk_application_props[PROP_ACTIVE_WINDOW]);
    }
}

static void
extract_accel_from_menu_item (GMenuModel     *model,
                              gint            item,
                              GtkApplication *app)
{
  GMenuAttributeIter *iter;
  const gchar *key;
  GVariant *value;
  const gchar *accel = NULL;
  const gchar *action = NULL;
  GVariant *target = NULL;

  iter = g_menu_model_iterate_item_attributes (model, item);
  while (g_menu_attribute_iter_get_next (iter, &key, &value))
    {
      if (g_str_equal (key, "action") && g_variant_is_of_type (value, G_VARIANT_TYPE_STRING))
        action = g_variant_get_string (value, NULL);
      else if (g_str_equal (key, "accel") && g_variant_is_of_type (value, G_VARIANT_TYPE_STRING))
        accel = g_variant_get_string (value, NULL);
      else if (g_str_equal (key, "target"))
        target = g_variant_ref (value);
      g_variant_unref (value);
    }
  g_object_unref (iter);

  if (accel && action)
    {
      const gchar *accels[2] = { accel, NULL };
      gchar *detailed_action_name;

      detailed_action_name = g_action_print_detailed_name (action, target);
      gtk_application_set_accels_for_action (app, detailed_action_name, accels);
      g_free (detailed_action_name);
    }

  if (target)
    g_variant_unref (target);
}

static void
extract_accels_from_menu (GMenuModel     *model,
                          GtkApplication *app)
{
  gint i;

  for (i = 0; i < g_menu_model_get_n_items (model); i++)
    {
      GMenuLinkIter *iter;
      GMenuModel *sub_model;

      extract_accel_from_menu_item (model, i, app);

      iter = g_menu_model_iterate_item_links (model, i);
      while (g_menu_link_iter_get_next (iter, NULL, &sub_model))
        {
          extract_accels_from_menu (sub_model, app);
          g_object_unref (sub_model);
        }
      g_object_unref (iter);
    }
}

static void
gtk_application_get_property (GObject    *object,
                              guint       prop_id,
                              GValue     *value,
                              GParamSpec *pspec)
{
  GtkApplication *application = GTK_APPLICATION (object);

  switch (prop_id)
    {
    case PROP_REGISTER_SESSION:
      g_value_set_boolean (value, application->priv->register_session);
      break;

    case PROP_SCREENSAVER_ACTIVE:
      g_value_set_boolean (value, application->priv->screensaver_active);
      break;

    case PROP_APP_MENU:
      g_value_set_object (value, gtk_application_get_app_menu (application));
      break;

    case PROP_MENUBAR:
      g_value_set_object (value, gtk_application_get_menubar (application));
      break;

    case PROP_ACTIVE_WINDOW:
      g_value_set_object (value, gtk_application_get_active_window (application));
      break;

    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
    }
}

static void
gtk_application_set_property (GObject      *object,
                              guint         prop_id,
                              const GValue *value,
                              GParamSpec   *pspec)
{
  GtkApplication *application = GTK_APPLICATION (object);

  switch (prop_id)
    {
    case PROP_REGISTER_SESSION:
      application->priv->register_session = g_value_get_boolean (value);
      break;

    case PROP_APP_MENU:
      gtk_application_set_app_menu (application, g_value_get_object (value));
      break;

    case PROP_MENUBAR:
      gtk_application_set_menubar (application, g_value_get_object (value));
      break;

    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
    }
}

static void
gtk_application_finalize (GObject *object)
{
  GtkApplication *application = GTK_APPLICATION (object);

  g_clear_object (&application->priv->menus_builder);
  g_clear_object (&application->priv->app_menu);
  g_clear_object (&application->priv->menubar);
  g_clear_object (&application->priv->muxer);
  g_clear_object (&application->priv->accels);

  g_free (application->priv->help_overlay_path);

  G_OBJECT_CLASS (gtk_application_parent_class)->finalize (object);
}

#ifdef G_OS_UNIX

static const gchar org_gnome_Sysprof3_Profiler_xml[] =
  "<node>"
    "<interface name='org.gnome.Sysprof3.Profiler'>"
      "<property name='Capabilities' type='a{sv}' access='read'/>"
      "<method name='Start'>"
        "<arg type='a{sv}' name='options' direction='in'/>"
        "<arg type='h' name='fd' direction='in'/>"
      "</method>"
      "<method name='Stop'>"
      "</method>"
    "</interface>"
  "</node>";

static GDBusInterfaceInfo *org_gnome_Sysprof3_Profiler;

static void
sysprof_profiler_method_call (GDBusConnection       *connection,
                              const gchar           *sender,
                              const gchar           *object_path,
                              const gchar           *interface_name,
                              const gchar           *method_name,
                              GVariant              *parameters,
                              GDBusMethodInvocation *invocation,
                              gpointer               user_data)
{
  if (strcmp (method_name, "Start") == 0)
    {
      GDBusMessage *message;
      GUnixFDList *fd_list;
      GVariant *options;
      int fd = -1;
      int idx;

      if (GDK_PRIVATE_CALL (gdk_profiler_is_running) ())
        {
          g_dbus_method_invocation_return_error (invocation,
                                                 G_DBUS_ERROR,
                                                 G_DBUS_ERROR_FAILED,
                                                 "Profiler already running");
          return;
        }

      g_variant_get (parameters, "(@a{sv}h)", &options, &idx);

      message = g_dbus_method_invocation_get_message (invocation);
      fd_list = g_dbus_message_get_unix_fd_list (message);
      if (fd_list)
        fd = g_unix_fd_list_get (fd_list, idx, NULL);

      GDK_PRIVATE_CALL (gdk_profiler_start) (fd);

      g_variant_unref (options);
    }
  else if (strcmp (method_name, "Stop") == 0)
    {
      if (!GDK_PRIVATE_CALL (gdk_profiler_is_running) ())
        {
          g_dbus_method_invocation_return_error (invocation,
                                                 G_DBUS_ERROR,
                                                 G_DBUS_ERROR_FAILED,
                                                 "Profiler not running");
          return;
        }

      GDK_PRIVATE_CALL (gdk_profiler_stop) ();
    }
  else
    {
      g_dbus_method_invocation_return_error (invocation,
                                             G_DBUS_ERROR,
                                             G_DBUS_ERROR_UNKNOWN_METHOD,
                                             "Unknown method");
      return;
    }

  g_dbus_method_invocation_return_value (invocation, NULL);
}

static gboolean
gtk_application_dbus_register (GApplication     *application,
                               GDBusConnection  *connection,
                               const char       *obect_path,
                               GError          **error)
{
  GtkApplicationPrivate *priv = gtk_application_get_instance_private (GTK_APPLICATION (application));
  GDBusInterfaceVTable vtable = {
    sysprof_profiler_method_call,
    NULL,
    NULL
  };

  if (org_gnome_Sysprof3_Profiler == NULL)
    {
      GDBusNodeInfo *info;

      info = g_dbus_node_info_new_for_xml (org_gnome_Sysprof3_Profiler_xml, error);
      if (info == NULL)
        return FALSE;

      org_gnome_Sysprof3_Profiler = g_dbus_node_info_lookup_interface (info, "org.gnome.Sysprof3.Profiler");
      g_dbus_interface_info_ref (org_gnome_Sysprof3_Profiler);
      g_dbus_node_info_unref (info);
    }

  priv->profiler_id = g_dbus_connection_register_object (connection,
                                                         "/org/gtk/Profiler",
                                                         org_gnome_Sysprof3_Profiler,
                                                         &vtable,
                                                         NULL,
                                                         NULL,
                                                         error);

  return TRUE;
}

static void
gtk_application_dbus_unregister (GApplication     *application,
                                 GDBusConnection  *connection,
                                 const char       *obect_path)
{
  GtkApplicationPrivate *priv = gtk_application_get_instance_private (GTK_APPLICATION (application));

  g_dbus_connection_unregister_object (connection, priv->profiler_id);
}

#else

static gboolean
gtk_application_dbus_register (GApplication     *application,
                               GDBusConnection  *connection,
                               const char       *obect_path,
                               GError          **error)
{
  return TRUE;
}

static void
gtk_application_dbus_unregister (GApplication     *application,
                                 GDBusConnection  *connection,
                                 const char       *obect_path)
{
}

#endif

static void
gtk_application_class_init (GtkApplicationClass *class)
{
  GObjectClass *object_class = G_OBJECT_CLASS (class);
  GApplicationClass *application_class = G_APPLICATION_CLASS (class);

  object_class->get_property = gtk_application_get_property;
  object_class->set_property = gtk_application_set_property;
  object_class->finalize = gtk_application_finalize;

  application_class->local_command_line = gtk_application_local_command_line;
  application_class->add_platform_data = gtk_application_add_platform_data;
  application_class->before_emit = gtk_application_before_emit;
  application_class->after_emit = gtk_application_after_emit;
  application_class->startup = gtk_application_startup;
  application_class->shutdown = gtk_application_shutdown;
  application_class->dbus_register = gtk_application_dbus_register;
  application_class->dbus_unregister = gtk_application_dbus_unregister;

  class->window_added = gtk_application_window_added;
  class->window_removed = gtk_application_window_removed;

  /**
   * GtkApplication::window-added:
   * @application: the #GtkApplication which emitted the signal
   * @window: the newly-added #GtkWindow
   *
   * Emitted when a #GtkWindow is added to @application through
   * gtk_application_add_window().
   *
   * Since: 3.2
   */
  gtk_application_signals[WINDOW_ADDED] =
    g_signal_new (I_("window-added"), GTK_TYPE_APPLICATION, G_SIGNAL_RUN_FIRST,
                  G_STRUCT_OFFSET (GtkApplicationClass, window_added),
                  NULL, NULL,
                  NULL,
                  G_TYPE_NONE, 1, GTK_TYPE_WINDOW);

  /**
   * GtkApplication::window-removed:
   * @application: the #GtkApplication which emitted the signal
   * @window: the #GtkWindow that is being removed
   *
   * Emitted when a #GtkWindow is removed from @application,
   * either as a side-effect of being destroyed or explicitly
   * through gtk_application_remove_window().
   *
   * Since: 3.2
   */
  gtk_application_signals[WINDOW_REMOVED] =
    g_signal_new (I_("window-removed"), GTK_TYPE_APPLICATION, G_SIGNAL_RUN_FIRST,
                  G_STRUCT_OFFSET (GtkApplicationClass, window_removed),
                  NULL, NULL,
                  NULL,
                  G_TYPE_NONE, 1, GTK_TYPE_WINDOW);

  /**
   * GtkApplication::query-end:
   * @application: the #GtkApplication which emitted the signal
   *
   * Emitted when the session manager is about to end the session, only
   * if #GtkApplication::register-session is %TRUE. Applications can
   * connect to this signal and call gtk_application_inhibit() with
   * %GTK_APPLICATION_INHIBIT_LOGOUT to delay the end of the session
   * until state has been saved.
   *
   * Since: 3.24.8
   */
  gtk_application_signals[QUERY_END] =
    g_signal_new (I_("query-end"), GTK_TYPE_APPLICATION, G_SIGNAL_RUN_FIRST,
                  0,
                  NULL, NULL,
                  NULL,
                  G_TYPE_NONE, 0);
  /**
   * GtkApplication:register-session:
   *
   * Set this property to %TRUE to register with the session manager.
   *
   * Since: 3.4
   */
  gtk_application_props[PROP_REGISTER_SESSION] =
    g_param_spec_boolean ("register-session",
                          P_("Register session"),
                          P_("Register with the session manager"),
                          FALSE,
                          G_PARAM_READWRITE|G_PARAM_STATIC_STRINGS);

  /**
   * GtkApplication:screensaver-active:
   *
   * This property is %TRUE if GTK+ believes that the screensaver is
   * currently active. GTK+ only tracks session state (including this)
   * when #GtkApplication::register-session is set to %TRUE.
   *
   * Tracking the screensaver state is supported on Linux.
   *
   * Since: 3.24
   */
  gtk_application_props[PROP_SCREENSAVER_ACTIVE] =
    g_param_spec_boolean ("screensaver-active",
                          P_("Screensaver Active"),
                          P_("Whether the screensaver is active"),
                          FALSE,
                          G_PARAM_READABLE|G_PARAM_STATIC_STRINGS);

  gtk_application_props[PROP_APP_MENU] =
    g_param_spec_object ("app-menu",
                         P_("Application menu"),
                         P_("The GMenuModel for the application menu"),
                         G_TYPE_MENU_MODEL,
                         G_PARAM_READWRITE|G_PARAM_STATIC_STRINGS);

  gtk_application_props[PROP_MENUBAR] =
    g_param_spec_object ("menubar",
                         P_("Menubar"),
                         P_("The GMenuModel for the menubar"),
                         G_TYPE_MENU_MODEL,
                         G_PARAM_READWRITE|G_PARAM_STATIC_STRINGS);

  gtk_application_props[PROP_ACTIVE_WINDOW] =
    g_param_spec_object ("active-window",
                         P_("Active window"),
                         P_("The window which most recently had focus"),
                         GTK_TYPE_WINDOW,
                         G_PARAM_READABLE|G_PARAM_STATIC_STRINGS);

  g_object_class_install_properties (object_class, NUM_PROPERTIES, gtk_application_props);
}

/**
 * gtk_application_new:
 * @application_id: (allow-none): The application ID.
 * @flags: the application flags
 *
 * Creates a new #GtkApplication instance.
 *
 * When using #GtkApplication, it is not necessary to call gtk_init()
 * manually. It is called as soon as the application gets registered as
 * the primary instance.
 *
 * Concretely, gtk_init() is called in the default handler for the
 * #GApplication::startup signal. Therefore, #GtkApplication subclasses should
 * chain up in their #GApplication::startup handler before using any GTK+ API.
 *
 * Note that commandline arguments are not passed to gtk_init().
 * All GTK+ functionality that is available via commandline arguments
 * can also be achieved by setting suitable environment variables
 * such as `G_DEBUG`, so this should not be a big
 * problem. If you absolutely must support GTK+ commandline arguments,
 * you can explicitly call gtk_init() before creating the application
 * instance.
 *
 * If non-%NULL, the application ID must be valid.  See
 * g_application_id_is_valid().
 *
 * If no application ID is given then some features (most notably application 
 * uniqueness) will be disabled. A null application ID is only allowed with 
 * GTK+ 3.6 or later.
 *
 * Returns: a new #GtkApplication instance
 *
 * Since: 3.0
 */
GtkApplication *
gtk_application_new (const gchar       *application_id,
                     GApplicationFlags  flags)
{
  g_return_val_if_fail (application_id == NULL || g_application_id_is_valid (application_id), NULL);

  return g_object_new (GTK_TYPE_APPLICATION,
                       "application-id", application_id,
                       "flags", flags,
                       NULL);
}

/**
 * gtk_application_add_window:
 * @application: a #GtkApplication
 * @window: a #GtkWindow
 *
 * Adds a window to @application.
 *
 * This call can only happen after the @application has started;
 * typically, you should add new application windows in response
 * to the emission of the #GApplication::activate signal.
 *
 * This call is equivalent to setting the #GtkWindow:application
 * property of @window to @application.
 *
 * Normally, the connection between the application and the window
 * will remain until the window is destroyed, but you can explicitly
 * remove it with gtk_application_remove_window().
 *
 * GTK+ will keep the @application running as long as it has
 * any windows.
 *
 * Since: 3.0
 **/
void
gtk_application_add_window (GtkApplication *application,
                            GtkWindow      *window)
{
  g_return_if_fail (GTK_IS_APPLICATION (application));
  g_return_if_fail (GTK_IS_WINDOW (window));

  if (!g_application_get_is_registered (G_APPLICATION (application)))
    {
      g_critical ("New application windows must be added after the "
                  "GApplication::startup signal has been emitted.");
      return;
    }

  if (!g_list_find (application->priv->windows, window))
    g_signal_emit (application,
                   gtk_application_signals[WINDOW_ADDED], 0, window);
}

/**
 * gtk_application_remove_window:
 * @application: a #GtkApplication
 * @window: a #GtkWindow
 *
 * Remove a window from @application.
 *
 * If @window belongs to @application then this call is equivalent to
 * setting the #GtkWindow:application property of @window to
 * %NULL.
 *
 * The application may stop running as a result of a call to this
 * function.
 *
 * Since: 3.0
 **/
void
gtk_application_remove_window (GtkApplication *application,
                               GtkWindow      *window)
{
  g_return_if_fail (GTK_IS_APPLICATION (application));