static void
egg_cell_renderer_keys_get_property  (GObject                  *object,
                                      guint                     param_id,
                                      GValue                   *value,
                                      GParamSpec               *pspec)
{
  EggCellRendererKeys *keys;

  g_return_if_fail (EGG_IS_CELL_RENDERER_KEYS (object));

  keys = EGG_CELL_RENDERER_KEYS (object);

  switch (param_id)
    {
    case PROP_ACCEL_KEY:
      g_value_set_uint (value, keys->accel_key);
      break;

    case PROP_ACCEL_MASK:
      g_value_set_flags (value, keys->accel_mask);
      break;

    case PROP_ACCEL_MODE:
      g_value_set_int (value, keys->accel_mode);
      break;

    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, param_id, pspec);
    }
}
static void ungrab_stuff(GtkWidget* widget, gpointer data)
{
	EggCellRendererKeys* keys = EGG_CELL_RENDERER_KEYS(data);

	gdk_keyboard_ungrab(GDK_CURRENT_TIME);
	gdk_pointer_ungrab(GDK_CURRENT_TIME);

	g_signal_handlers_disconnect_by_func(G_OBJECT(keys->grab_widget), G_CALLBACK(grab_key_callback), data);
}
static void ungrab_stuff(GtkWidget* widget, gpointer data)
{
	EggCellRendererKeys* keys = EGG_CELL_RENDERER_KEYS(data);
	GdkDisplay *display;
	GdkSeat *seat;

	display = gtk_widget_get_display (widget);
	seat = gdk_display_get_default_seat (display);

	gdk_seat_ungrab (seat);

	g_signal_handlers_disconnect_by_func(G_OBJECT(keys->grab_widget), G_CALLBACK(grab_key_callback), data);
}
static GtkCellEditable *
egg_cell_renderer_keys_start_editing (GtkCellRenderer      *cell,
				      GdkEvent             *event,
				      GtkWidget            *widget,
				      const gchar          *path,
				      GdkRectangle         *background_area,
				      GdkRectangle         *cell_area,
				      GtkCellRendererState  flags)
{
  GtkCellRendererText *celltext;
  EggCellRendererKeys *keys;
  GtkWidget *label;
  GtkWidget *eventbox;
  GValue celltext_editable = {0};

  celltext = GTK_CELL_RENDERER_TEXT (cell);
  keys = EGG_CELL_RENDERER_KEYS (cell);

  /* If the cell isn't editable we return NULL. */
  g_value_init (&celltext_editable, G_TYPE_BOOLEAN);
  g_object_get_property (G_OBJECT (celltext), "editable", &celltext_editable);
  if (g_value_get_boolean (&celltext_editable) == FALSE)
    return NULL;
  g_return_val_if_fail (gtk_widget_get_window (widget) != NULL, NULL);

  if (gdk_keyboard_grab (gtk_widget_get_window (widget), FALSE,
                         gdk_event_get_time (event)) != GDK_GRAB_SUCCESS)
    return NULL;

  if (gdk_pointer_grab (gtk_widget_get_window (widget), FALSE,
                        GDK_BUTTON_PRESS_MASK,
                        NULL, NULL,
                        gdk_event_get_time (event)) != GDK_GRAB_SUCCESS)
    {
      gdk_keyboard_ungrab (gdk_event_get_time (event));
      return NULL;
    }

  keys->grab_widget = widget;

  g_signal_connect (G_OBJECT (widget), "key_press_event",
                    G_CALLBACK (grab_key_callback),
                    keys);

  eventbox = g_object_new (pointless_eventbox_subclass_get_type (),
                           NULL);
  keys->edit_widget = eventbox;
  g_object_add_weak_pointer (G_OBJECT (keys->edit_widget),
                             (void**) &keys->edit_widget);

  label = gtk_label_new (NULL);
  gtk_misc_set_alignment (GTK_MISC (label), 0.0, 0.5);

  gtk_widget_modify_bg (eventbox, GTK_STATE_NORMAL,
                        &gtk_widget_get_style (widget)->bg[GTK_STATE_SELECTED]);

  gtk_widget_modify_fg (label, GTK_STATE_NORMAL,
                        &gtk_widget_get_style (widget)->fg[GTK_STATE_SELECTED]);

  gtk_label_set_text (GTK_LABEL (label),
		  TOOLTIP_TEXT);

  gtk_container_add (GTK_CONTAINER (eventbox), label);

  g_object_set_data_full (G_OBJECT (keys->edit_widget), EGG_CELL_RENDERER_TEXT_PATH,
                          g_strdup (path), g_free);

  gtk_widget_show_all (keys->edit_widget);

  g_signal_connect (G_OBJECT (keys->edit_widget), "unrealize",
                    G_CALLBACK (ungrab_stuff), keys);

  keys->edit_key = keys->accel_key;

  return GTK_CELL_EDITABLE (keys->edit_widget);
}
static gboolean grab_key_callback(GtkWidget* widget, GdkEventKey* event, void* data)
{
	GdkModifierType accel_mods = 0;
	guint accel_keyval;
	EggCellRendererKeys *keys;
	char *path;
	gboolean edited;
	gboolean cleared;
	GdkModifierType consumed_modifiers;
	guint upper;
	GdkModifierType ignored_modifiers;

	keys = EGG_CELL_RENDERER_KEYS(data);

	if (is_modifier(event->hardware_keycode))
	{
		return TRUE;
	}

	edited = FALSE;
	cleared = FALSE;

	consumed_modifiers = 0;
	gdk_keymap_translate_keyboard_state(gdk_keymap_get_default(),
		event->hardware_keycode,
		event->state,
		event->group,
		NULL, NULL, NULL, &consumed_modifiers);

	upper = event->keyval;
	accel_keyval = gdk_keyval_to_lower(upper);

	if (accel_keyval == GDK_ISO_Left_Tab)
	{
		accel_keyval = GDK_Tab;
	}

	/* Put shift back if it changed the case of the key, not otherwise. */
	if (upper != accel_keyval && (consumed_modifiers & GDK_SHIFT_MASK))
	{
		consumed_modifiers &= ~(GDK_SHIFT_MASK);
	}

	egg_keymap_resolve_virtual_modifiers(gdk_keymap_get_default(),
		EGG_VIRTUAL_NUM_LOCK_MASK |
		EGG_VIRTUAL_SCROLL_LOCK_MASK |
		EGG_VIRTUAL_LOCK_MASK,
		&ignored_modifiers);

	/* http://bugzilla.gnome.org/show_bug.cgi?id=139605
	 * mouse keys should effect keybindings */
	ignored_modifiers |= GDK_BUTTON1_MASK |
		GDK_BUTTON2_MASK |
		GDK_BUTTON3_MASK |
		GDK_BUTTON4_MASK |
		GDK_BUTTON5_MASK;

	/* filter consumed/ignored modifiers */
	if (keys->accel_mode == EGG_CELL_RENDERER_KEYS_MODE_GTK)
	{
		accel_mods = event->state & GDK_MODIFIER_MASK & ~(consumed_modifiers | ignored_modifiers);
	}
	else if (keys->accel_mode == EGG_CELL_RENDERER_KEYS_MODE_X)
	{
		accel_mods = event->state & GDK_MODIFIER_MASK & ~(ignored_modifiers);
	}
	else
	{
		g_assert_not_reached();
	}

	if (accel_mods == 0 && accel_keyval == GDK_Escape)
	{
		goto out; /* cancel */
	}

	/* clear the accelerator on Backspace */
	if (accel_mods == 0 && accel_keyval == GDK_BackSpace)
	{
		cleared = TRUE;
		goto out;
	}

	if (keys->accel_mode == EGG_CELL_RENDERER_KEYS_MODE_GTK)
	{
		if (!gtk_accelerator_valid (accel_keyval, accel_mods))
		{
			accel_keyval = 0;
			accel_mods = 0;
		}
	}

	edited = TRUE;

	out:

	gdk_keyboard_ungrab(event->time);
	gdk_pointer_ungrab(event->time);

	path = g_strdup(g_object_get_data(G_OBJECT(keys->edit_widget), EGG_CELL_RENDERER_TEXT_PATH));

	gtk_cell_editable_editing_done(GTK_CELL_EDITABLE(keys->edit_widget));
	gtk_cell_editable_remove_widget(GTK_CELL_EDITABLE(keys->edit_widget));
	keys->edit_widget = NULL;
	keys->grab_widget = NULL;

	if (edited)
	{
		g_signal_emit_by_name(G_OBJECT(keys), "accel_edited", path, accel_keyval, accel_mods, event->hardware_keycode);
	}
	else if (cleared)
	{
		g_signal_emit_by_name(G_OBJECT(keys), "accel_cleared", path);
	}

	g_free (path);
	return TRUE;
}