power: Do not emit multiple 'Changed' signals when recalculating

We were issuing up to three changed signals, and always doing at least one when
nothing had actually changed.
Ensure we only send one signal, and only send that if something was different
from before.

Resolves https://bugzilla.gnome.org/show_bug.cgi?id=659204

1 files changed, 16 insertions, 14 deletions

diff --git a/plugins/power/gsd-power-manager.c b/plugins/power/gsd-power-manager.c
index c1008dc3..f0b7d5b8 100644
--- a/plugins/power/gsd-power-manager.c
+++ b/plugins/power/gsd-power-manager.c
@@ -631,10 +631,6 @@ engine_recalculate_state_icon (GsdPowerManager *manager)
 
                 /* set fallback icon */
                 gtk_status_icon_set_visible (manager->priv->status_icon, FALSE);
-
-                /* icon before, now none */
-                engine_emit_changed (manager);
-
                 return TRUE;
         }
 
@@ -644,8 +640,6 @@ engine_recalculate_state_icon (GsdPowerManager *manager)
                 /* set fallback icon */
                 gtk_status_icon_set_visible (manager->priv->status_icon, TRUE);
                 gtk_status_icon_set_from_gicon (manager->priv->status_icon, icon);
-
-                engine_emit_changed (manager);
                 manager->priv->previous_icon = icon;
                 return TRUE;
         }
@@ -657,8 +651,6 @@ engine_recalculate_state_icon (GsdPowerManager *manager)
 
                 /* set fallback icon */
                 gtk_status_icon_set_from_gicon (manager->priv->status_icon, icon);
-
-                engine_emit_changed (manager);
                 return TRUE;
         }
 
@@ -681,7 +673,6 @@ engine_recalculate_state_summary (GsdPowerManager *manager)
                 gtk_status_icon_set_tooltip_text (manager->priv->status_icon,
                                                   summary);
 
-                engine_emit_changed (manager);
                 return TRUE;
         }
 
@@ -693,7 +684,6 @@ engine_recalculate_state_summary (GsdPowerManager *manager)
                 gtk_status_icon_set_tooltip_text (manager->priv->status_icon,
                                                   summary);
 
-                engine_emit_changed (manager);
                 return TRUE;
         }
         g_debug ("no change");
@@ -705,10 +695,19 @@ engine_recalculate_state_summary (GsdPowerManager *manager)
 static void
 engine_recalculate_state (GsdPowerManager *manager)
 {
-        engine_recalculate_state_icon (manager);
-        engine_recalculate_state_summary (manager);
+        gboolean ret;
+        gboolean has_changed = FALSE;
 
-        engine_emit_changed (manager);
+        ret = engine_recalculate_state_icon (manager);
+        if (ret)
+                has_changed = TRUE;
+        ret = engine_recalculate_state_summary (manager);
+        if (ret)
+                has_changed = TRUE;
+
+        /* only emit if the icon or summary has changed */
+        if (has_changed)
+                engine_emit_changed (manager);
 }
 
 static UpDevice *
@@ -770,6 +769,7 @@ engine_update_composite_device (GsdPowerManager *manager,
         gboolean is_charging = FALSE;
         gboolean is_discharging = FALSE;
         gboolean is_fully_charged = TRUE;
+        gboolean has_changed;
         GPtrArray *array;
         UpDevice *device;
         UpDeviceState state;
@@ -854,7 +854,9 @@ engine_update_composite_device (GsdPowerManager *manager,
                       NULL);
 
         /* force update of icon */
-        engine_recalculate_state_icon (manager);
+        has_changed = engine_recalculate_state_icon (manager);
+        if (has_changed)
+                engine_emit_changed (manager);
 out:
         /* return composite device or original device */
         return device;