Bug 889621 - Lazy load all fragments in about:home (r=sriram)

mobile/android/base/home/BookmarksPage.java

@@ -152,11 +152,7 @@ public class BookmarksPage extends HomeFragment {
         // Create callbacks before the initial loader is started.
         mLoaderCallbacks = new CursorLoaderCallbacks();
         mThumbnailsLoaderCallbacks = new ThumbnailsLoaderCallbacks();
-
-        // Reconnect to the loader only if present.
-        final LoaderManager manager = getLoaderManager();
-        manager.initLoader(BOOKMARKS_LIST_LOADER_ID, null, mLoaderCallbacks);
-        manager.initLoader(TOP_BOOKMARKS_LOADER_ID, null, mLoaderCallbacks);
+        loadIfVisible();
     }
 
     @Override
@@ -291,6 +287,13 @@ public class BookmarksPage extends HomeFragment {
         return false;
     }
 
+    @Override
+    protected void load() {
+        final LoaderManager manager = getLoaderManager();
+        manager.initLoader(BOOKMARKS_LIST_LOADER_ID, null, mLoaderCallbacks);
+        manager.initLoader(TOP_BOOKMARKS_LOADER_ID, null, mLoaderCallbacks);
+    }
+
     /**
      * Listener for pinning bookmarks.
      */

mobile/android/base/home/BrowserSearch.java

@@ -246,9 +246,7 @@ public class BrowserSearch extends HomeFragment
 
         // Create callbacks before the initial loader is started
         mCursorLoaderCallbacks = new CursorLoaderCallbacks();
-
-        // Reconnect to the loader only if present
-        getLoaderManager().initLoader(SEARCH_LOADER_ID, null, mCursorLoaderCallbacks);
+        loadIfVisible();
     }
 
     @Override
@@ -263,6 +261,11 @@ public class BrowserSearch extends HomeFragment
         }
     }
 
+    @Override
+    protected void load() {
+        getLoaderManager().initLoader(SEARCH_LOADER_ID, null, mCursorLoaderCallbacks);
+    }
+
     private void handleAutocomplete(String searchTerm, Cursor c) {
         if (TextUtils.isEmpty(mSearchTerm) || c == null || mAutocompleteHandler == null) {
             return;

mobile/android/base/home/HistoryPage.java

@@ -150,8 +150,11 @@ public class HistoryPage extends HomeFragment {
 
         // Create callbacks before the initial loader is started
         mCursorLoaderCallbacks = new CursorLoaderCallbacks();
+        loadIfVisible();
+    }
 
-        // Reconnect to the loader only if present
+    @Override
+    protected void load() {
         getLoaderManager().initLoader(HISTORY_LOADER_ID, null, mCursorLoaderCallbacks);
     }
 

mobile/android/base/home/HomeFragment.java

@@ -36,7 +36,7 @@ import android.widget.Toast;
  * HomeFragment is an empty fragment that can be added to the HomePager.
  * Subclasses can add their own views. 
  */
-class HomeFragment extends Fragment {
+abstract class HomeFragment extends Fragment {
     // Log Tag.
     private static final String LOGTAG="GeckoHomeFragment";
 
@@ -184,4 +184,20 @@ class HomeFragment extends Fragment {
         }
         return false;
     }
+
+    @Override
+    public void setUserVisibleHint (boolean isVisibleToUser) {
+        super.setUserVisibleHint(isVisibleToUser);
+        loadIfVisible();
+    }
+
+    protected abstract void load();
+
+    protected void loadIfVisible() {
+        if (!isVisible() || !getUserVisibleHint()) {
+            return;
+        }
+
+        load();
+    }
 }

mobile/android/base/home/LastTabsPage.java

@@ -145,8 +145,11 @@ public class LastTabsPage extends HomeFragment {
 
         // Create callbacks before the initial loader is started
         mCursorLoaderCallbacks = new CursorLoaderCallbacks();
+        loadIfVisible();
+    }
 
-        // Reconnect to the loader only if present
+    @Override
+    protected void load() {
         getLoaderManager().initLoader(LAST_TABS_LOADER_ID, null, mCursorLoaderCallbacks);
     }
 

mobile/android/base/home/ReadingListPage.java

@@ -108,8 +108,11 @@ public class ReadingListPage extends HomeFragment {
 
         // Create callbacks before the initial loader is started.
         mCursorLoaderCallbacks = new CursorLoaderCallbacks();
+        loadIfVisible();
+    }
 
-        // Reconnect to the loader only if it's present.
+    @Override
+    protected void load() {
         getLoaderManager().initLoader(READING_LIST_LOADER_ID, null, mCursorLoaderCallbacks);
     }
 

mobile/android/base/home/VisitedPage.java

@@ -142,8 +142,11 @@ public class VisitedPage extends HomeFragment {
 
         // Create callbacks before the initial loader is started
         mCursorLoaderCallbacks = new CursorLoaderCallbacks();
+        loadIfVisible();
+    }
 
-        // Reconnect to the loader only if present
+    @Override
+    protected void load() {
         getLoaderManager().initLoader(FRECENCY_LOADER_ID, null, mCursorLoaderCallbacks);
     }