Media Galleries: Add MediaGalleriesPreferences::GalleryChangeObserver class.

chrome/browser/media_gallery/media_galleries_preferences.cc

Index: chrome/browser/media_gallery/media_galleries_preferences.cc
===================================================================
--- chrome/browser/media_gallery/media_galleries_preferences.cc	(revision 179736)
+++ chrome/browser/media_gallery/media_galleries_preferences.cc	(working copy)
@@ -136,10 +136,12 @@
   return base_path.Append(path);
 }
 
+MediaGalleriesPreferences::GalleryChangeObserver::~GalleryChangeObserver() {}
+
 MediaGalleriesPreferences::MediaGalleriesPreferences(Profile* profile)
     : profile_(profile) {
   AddDefaultGalleriesIfFreshProfile();
-  InitFromPrefs();
+  InitFromPrefs(false /*no notification*/);
 }
 
 MediaGalleriesPreferences::~MediaGalleriesPreferences() {}
@@ -171,15 +173,18 @@
   }
 }
 
-void MediaGalleriesPreferences::InitFromPrefs() {
+void MediaGalleriesPreferences::InitFromPrefs(bool notify_observers) {
   known_galleries_.clear();
   device_map_.clear();
 
   PrefService* prefs = profile_->GetPrefs();
   const ListValue* list = prefs->GetList(
       prefs::kMediaGalleriesRememberedGalleries);
-  if (!list)
+  if (!list) {

[vandebo (ex-Chrome), 2013/01/31 01:27:56]

To remove the code duplication, what do you think about putting the for loop in
an if (list) block and removing the early exit?

[Lei Zhang, 2013/01/31 01:34:35]

Done.

+    if (notify_observers)
+      NotifyChangeObservers();
     return;
+  }
 
   for (ListValue::const_iterator it = list->begin(); it != list->end(); ++it) {
     const DictionaryValue* dict = NULL;
@@ -193,8 +198,26 @@
     known_galleries_[gallery_info.pref_id] = gallery_info;
     device_map_[gallery_info.device_id].insert(gallery_info.pref_id);
   }
+  if (notify_observers)
+    NotifyChangeObservers();
 }
 
+void MediaGalleriesPreferences::NotifyChangeObservers() {
+  FOR_EACH_OBSERVER(GalleryChangeObserver,
+                    gallery_change_observers_,
+                    OnGalleryChanged(this));
+}
+
+void MediaGalleriesPreferences::AddGalleryChangeObserver(
+    GalleryChangeObserver* observer) {
+  gallery_change_observers_.AddObserver(observer);
+}
+
+void MediaGalleriesPreferences::RemoveGalleryChangeObserver(
+    GalleryChangeObserver* observer) {
+  gallery_change_observers_.RemoveObserver(observer);
+}
+
 bool MediaGalleriesPreferences::LookUpGalleryByPath(
     const FilePath& path,
     MediaGalleryPrefInfo* gallery_info) const {
@@ -281,7 +304,7 @@
           }
           if (update_gallery_name)
             dict->SetString(kMediaGalleriesDisplayNameKey, display_name);
-          InitFromPrefs();
+          InitFromPrefs(true /* notify observers */);
           break;
         }
       }
@@ -304,7 +327,7 @@
   ListPrefUpdate update(prefs, prefs::kMediaGalleriesRememberedGalleries);
   ListValue* list = update.Get();
   list->Append(CreateGalleryPrefInfoDictionary(gallery_info));
-  InitFromPrefs();
+  InitFromPrefs(true /* notify observers */);
 
   return gallery_info.pref_id;
 }
@@ -342,7 +365,7 @@
       } else {
         list->Erase(iter, NULL);
       }
-      InitFromPrefs();
+      InitFromPrefs(true /* notify observers */);
       return;
     }
   }