Sync search result loaders

The loaders should be syncronized so the results can be
properly ranked without sudden insertions.

This means InstalledAppsLoader needs to finish faster,
which is accomplished by delaying icon loading to bind time
rather than as the apps are queried.

Bug: 34772522
Test: make RunSettingsRoboTests
Change-Id: I7f5244c574d37c6cfd8bbd0d3d40488f38211be3

src/com/android/settings/search2/SearchFragment.java

@@ -41,9 +41,11 @@ import com.android.settings.core.instrumentation.MetricsFeatureProvider;
 import com.android.settings.overlay.FeatureFactory;
 
 import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
 
 public class SearchFragment extends InstrumentedFragment implements
-        SearchView.OnQueryTextListener, LoaderManager.LoaderCallbacks<List<SearchResult>> {
+        SearchView.OnQueryTextListener, LoaderManager.LoaderCallbacks<List<? extends SearchResult>>
+{
     private static final String TAG = "SearchFragment";
 
     // State values
@@ -56,6 +58,11 @@ public class SearchFragment extends InstrumentedFragment implements
     private static final int LOADER_ID_DATABASE = 1;
     private static final int LOADER_ID_INSTALLED_APPS = 2;
 
+    private static final int NUM_QUERY_LOADERS = 2;
+
+    @VisibleForTesting(otherwise = VisibleForTesting.PRIVATE)
+    AtomicInteger mUnfinishedLoadersCount = new AtomicInteger(NUM_QUERY_LOADERS);;
+
     // Logging
     @VisibleForTesting(otherwise = VisibleForTesting.PRIVATE)
     static final String RESULT_CLICK_COUNT = "settings_search_result_click_count";
@@ -69,9 +76,13 @@ public class SearchFragment extends InstrumentedFragment implements
     private boolean mNeverEnteredQuery = true;
     private int mResultClickCount;
     private MetricsFeatureProvider mMetricsFeatureProvider;
-    private SearchFeatureProvider mSearchFeatureProvider;
 
-    private SearchResultsAdapter mSearchAdapter;
+    @VisibleForTesting (otherwise = VisibleForTesting.PRIVATE)
+    SearchFeatureProvider mSearchFeatureProvider;
+
+    @VisibleForTesting(otherwise = VisibleForTesting.PRIVATE)
+    SearchResultsAdapter mSearchAdapter;
+
     private RecyclerView mResultsRecyclerView;
     private SearchView mSearchView;
 
@@ -92,7 +103,9 @@ public class SearchFragment extends InstrumentedFragment implements
         super.onCreate(savedInstanceState);
         setHasOptionsMenu(true);
         mSearchAdapter = new SearchResultsAdapter(this);
+
         final LoaderManager loaderManager = getLoaderManager();
+
         if (savedInstanceState != null) {
             mQuery = savedInstanceState.getString(STATE_QUERY);
             mNeverEnteredQuery = savedInstanceState.getBoolean(STATE_NEVER_ENTERED_QUERY);
@@ -181,7 +194,7 @@ public class SearchFragment extends InstrumentedFragment implements
     }
 
     @Override
-    public Loader<List<SearchResult>> onCreateLoader(int id, Bundle args) {
+    public Loader<List<? extends SearchResult>> onCreateLoader(int id, Bundle args) {
         final Activity activity = getActivity();
 
         switch (id) {
@@ -197,12 +210,17 @@ public class SearchFragment extends InstrumentedFragment implements
     }
 
     @Override
-    public void onLoadFinished(Loader<List<SearchResult>> loader, List<SearchResult> data) {
-        mSearchAdapter.mergeResults(data, loader.getClass().getName());
+    public void onLoadFinished(Loader<List<? extends SearchResult>> loader,
+            List<? extends SearchResult> data) {
+        mSearchAdapter.addResultsToMap(data, loader.getClass().getName());
+
+        if (mUnfinishedLoadersCount.decrementAndGet() == 0) {
+            mSearchAdapter.mergeResults();
+        }
     }
 
     @Override
-    public void onLoaderReset(Loader<List<SearchResult>> loader) {
+    public void onLoaderReset(Loader<List<? extends SearchResult>> loader) {
     }
 
     public void onSearchResultClicked() {
@@ -217,6 +235,7 @@ public class SearchFragment extends InstrumentedFragment implements
 
     private void restartLoaders() {
         final LoaderManager loaderManager = getLoaderManager();
+        mUnfinishedLoadersCount.set(NUM_QUERY_LOADERS);
         loaderManager.restartLoader(LOADER_ID_DATABASE, null /* args */, this /* callback */);
         loaderManager.restartLoader(LOADER_ID_INSTALLED_APPS, null /* args */, this /* callback */);
     }