[gnome-control-center] power: Improve keyboard navigation

[Matthias Clasen <matthiasc src gnome org>]

commit 501056eb01e577f4c3242feb3220c6eb9a595f22
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Jan 22 21:42:18 2013 -0500

    power: Improve keyboard navigation
    
    This commit 'links' the arrow navigation between the list boxes
    in the power page, so that it becomes possible to arrow down all
    the way from the battery section to automatic suspend. We also
    set up the focus adjustment so that the focus row gets scrolled
    into view.
    
    This requires the egg-list-box module to have
    commit 98b0a39efe7b1892570ece53748ab153a91b9cbc.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=692171

 panels/power/cc-power-panel.c |   76 +++++++++++++++++++++++++++++++++++++++-
 1 files changed, 74 insertions(+), 2 deletions(-)
---
diff --git a/panels/power/cc-power-panel.c b/panels/power/cc-power-panel.c
index 31c0386..bef9365 100644
--- a/panels/power/cc-power-panel.c
+++ b/panels/power/cc-power-panel.c
@@ -87,11 +87,13 @@ struct _CcPowerPanelPrivate
   GtkWidget     *device_section;
   GtkWidget     *device_list;
 
+  GtkWidget     *power_saving_list;
   GtkWidget     *dim_screen_row;
   GtkWidget     *brightness_row;
   GtkWidget     *brightness_scale;
   gboolean       setting_brightness;
 
+  GtkWidget     *automatic_suspend_list;
   GtkWidget     *automatic_suspend_row;
   GtkWidget     *automatic_suspend_label;
   GtkWidget     *critical_battery_row;
@@ -109,6 +111,8 @@ struct _CcPowerPanelPrivate
   GtkWidget     *mobile_switch;
   GtkWidget     *mobile_row;
 #endif
+
+  GtkAdjustment *focus_adjustment;
 };
 
 enum
@@ -1284,6 +1288,67 @@ nm_device_changed (NMClient     *client,
 
 #endif
 
+static gboolean
+keynav_failed (GtkWidget *list, GtkDirectionType direction, CcPowerPanel *self)
+{
+  CcPowerPanelPrivate *priv = self->priv;
+  GtkWidget *next_list = NULL;
+  gdouble value, lower, upper, page;
+
+  if (direction == GTK_DIR_DOWN)
+    {
+      if (list == priv->battery_list)
+        {
+          if (gtk_widget_is_visible (priv->device_list))
+            next_list = priv->device_list;
+          else
+            next_list = priv->power_saving_list;
+        }
+      else if (list == priv->device_list)
+        next_list = priv->power_saving_list;
+      else if (list == priv->power_saving_list)
+        next_list = priv->automatic_suspend_list;
+    }
+  else if (direction == GTK_DIR_UP)
+    {
+      if (list == priv->device_list)
+        next_list = priv->battery_list;
+      else if (list == priv->power_saving_list)
+        {
+          if (gtk_widget_is_visible (priv->device_list))
+            next_list = priv->device_list;
+          else
+            next_list = priv->battery_list;
+        }
+      else if (list == priv->automatic_suspend_list)
+        next_list = priv->power_saving_list;
+    }
+
+  if (next_list)
+    {
+      gtk_widget_child_focus (next_list, direction);
+      return TRUE;
+    }
+
+  value = gtk_adjustment_get_value (priv->focus_adjustment);
+  lower = gtk_adjustment_get_lower (priv->focus_adjustment);
+  upper = gtk_adjustment_get_upper (priv->focus_adjustment);
+  page  = gtk_adjustment_get_page_size (priv->focus_adjustment);
+
+  if (direction == GTK_DIR_UP && value > lower)
+    {
+      gtk_adjustment_set_value (priv->focus_adjustment, lower);
+      return TRUE;
+    }
+  else if (direction == GTK_DIR_DOWN && value < upper - page)
+    {
+      gtk_adjustment_set_value (priv->focus_adjustment, upper - page);
+      return TRUE;
+    }
+
+  return FALSE;
+}
+
 static void
 combo_idle_delay_changed_cb (GtkWidget *widget, CcPowerPanel *self)
 {
@@ -1332,7 +1397,8 @@ add_power_saving_section (CcPowerPanel *self)
   gtk_box_pack_start (GTK_BOX (vbox), widget, FALSE, TRUE, 0);
   gtk_widget_show (widget);
 
-  widget = GTK_WIDGET (egg_list_box_new ());
+  priv->power_saving_list = widget = GTK_WIDGET (egg_list_box_new ());
+  g_signal_connect (widget, "keynav-failed", G_CALLBACK (keynav_failed), self);
   egg_list_box_set_selection_mode (EGG_LIST_BOX (widget), GTK_SELECTION_NONE);
   egg_list_box_set_separator_funcs (EGG_LIST_BOX (widget),
                                     update_separator_func,
@@ -1681,7 +1747,8 @@ add_automatic_suspend_section (CcPowerPanel *self)
   gtk_box_pack_start (GTK_BOX (vbox), widget, FALSE, TRUE, 0);
   gtk_widget_show (widget);
 
-  widget = GTK_WIDGET (egg_list_box_new ());
+  priv->automatic_suspend_list = widget = GTK_WIDGET (egg_list_box_new ());
+  g_signal_connect (widget, "keynav-failed", G_CALLBACK (keynav_failed), self);
   egg_list_box_set_selection_mode (EGG_LIST_BOX (widget), GTK_SELECTION_NONE);
   egg_list_box_set_separator_funcs (EGG_LIST_BOX (widget),
                                     update_separator_func,
@@ -1853,6 +1920,7 @@ add_battery_section (CcPowerPanel *self)
   gtk_box_pack_start (GTK_BOX (box), widget, FALSE, TRUE, 0);
 
   priv->battery_list = widget = GTK_WIDGET (egg_list_box_new ());
+  g_signal_connect (widget, "keynav-failed", G_CALLBACK (keynav_failed), self);
   egg_list_box_set_selection_mode (EGG_LIST_BOX (widget), GTK_SELECTION_NONE);
   egg_list_box_set_separator_funcs (EGG_LIST_BOX (widget),
                                     update_separator_func,
@@ -1902,6 +1970,7 @@ add_device_section (CcPowerPanel *self)
   gtk_box_pack_start (GTK_BOX (box), widget, FALSE, TRUE, 0);
 
   priv->device_list = widget = GTK_WIDGET (egg_list_box_new ());
+  g_signal_connect (widget, "keynav-failed", G_CALLBACK (keynav_failed), self);
   egg_list_box_set_selection_mode (EGG_LIST_BOX (widget), GTK_SELECTION_NONE);
   egg_list_box_set_separator_funcs (EGG_LIST_BOX (widget),
                                     update_separator_func,
@@ -2009,4 +2078,7 @@ cc_power_panel_init (CcPowerPanel *self)
   gtk_widget_unparent (widget);
   gtk_scrolled_window_add_with_viewport (GTK_SCROLLED_WINDOW (box), widget);
   g_object_unref (widget);
+
+  priv->focus_adjustment = gtk_scrolled_window_get_vadjustment (GTK_SCROLLED_WINDOW (box));
+  gtk_container_set_focus_vadjustment (GTK_CONTAINER (widget), priv->focus_adjustment);
 }