Make UI refresh when there is only one contextual card left.

After having card dismissal mechanism implemented, it is possible that
the card list loaded from the card loader will be empty (users may
dismiss all cards). When there is only one card remaining on the screen
and user dismiss it, the card should go away.

Fixes: 119580732
Test: robotest
Change-Id: I7ae3b03f16a0b8b009d8aa77811b5a6d39c359e7

src/com/android/settings/homepage/contextualcards/ContextualCardManager.java

@@ -62,10 +62,12 @@ public class ContextualCardManager implements ContextualCardLoader.CardContentLo
     private static final int[] SETTINGS_CARDS =
             {ContextualCard.CardType.CONDITIONAL, ContextualCard.CardType.LEGACY_SUGGESTION};
 
+    @VisibleForTesting
+    final List<ContextualCard> mContextualCards;
+
     private final Context mContext;
     private final ControllerRendererPool mControllerRendererPool;
     private final Lifecycle mLifecycle;
-    private final List<ContextualCard> mContextualCards;
     private final List<LifecycleObserver> mLifecycleObservers;
 
     private ContextualCardUpdateListener mListener;
@@ -122,10 +124,23 @@ public class ContextualCardManager implements ContextualCardLoader.CardContentLo
     public void onContextualCardUpdated(Map<Integer, List<ContextualCard>> updateList) {
         final Set<Integer> cardTypes = updateList.keySet();
         //Remove the existing data that matches the certain cardType before inserting new data.
-        final List<ContextualCard> cardsToKeep = mContextualCards
+        List<ContextualCard> cardsToKeep;
-                .stream()
+
+        // We are not sure how many card types will be in the database, so when the list coming
+        // from the database is empty (e.g. no eligible cards/cards are dismissed), we cannot
+        // assign a specific card type for its map which is sending here. Thus, we assume that
+        // except Conditional cards, all other cards are from the database. So when the map sent
+        // here is empty, we only keep Conditional cards.
+        if (cardTypes.isEmpty()) {
+            cardsToKeep = mContextualCards.stream()
+                    .filter(card -> card.getCardType() == ContextualCard.CardType.CONDITIONAL)
+                    .collect(Collectors.toList());
+        } else {
+            cardsToKeep = mContextualCards.stream()
                     .filter(card -> !cardTypes.contains(card.getCardType()))
                     .collect(Collectors.toList());
+        }
+
         final List<ContextualCard> allCards = new ArrayList<>();
         allCards.addAll(cardsToKeep);
         allCards.addAll(

tests/robotests/src/com/android/settings/homepage/contextualcards/ContextualCardManagerTest.java

@@ -18,8 +18,12 @@ package com.android.settings.homepage.contextualcards;
 
 import static com.google.common.truth.Truth.assertThat;
 
+import static org.mockito.ArgumentMatchers.anyMap;
+import static org.mockito.Mockito.doNothing;
+
 import android.content.Context;
 import android.net.Uri;
+import android.util.ArrayMap;
 
 import com.android.settings.homepage.contextualcards.conditional.ConditionalContextualCard;
 import com.android.settings.testutils.SettingsRobolectricTestRunner;
@@ -27,6 +31,8 @@ import com.android.settings.testutils.SettingsRobolectricTestRunner;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
 import org.robolectric.RuntimeEnvironment;
 
 import java.util.ArrayList;
@@ -35,11 +41,17 @@ import java.util.List;
 @RunWith(SettingsRobolectricTestRunner.class)
 public class ContextualCardManagerTest {
 
+    private static final String TEST_SLICE_URI = "context://test/test";
+
+    @Mock
+    ContextualCardUpdateListener mListener;
+
     private Context mContext;
     private ContextualCardManager mManager;
 
     @Before
     public void setUp() {
+        MockitoAnnotations.initMocks(this);
         mContext = RuntimeEnvironment.application;
         final ContextualCardsFragment fragment = new ContextualCardsFragment();
         mManager = new ContextualCardManager(mContext, fragment.getSettingsLifecycle());
@@ -47,10 +59,9 @@ public class ContextualCardManagerTest {
 
     @Test
     public void sortCards_hasConditionalAndSliceCards_conditionalShouldAlwaysBeTheLast() {
-        final String sliceUri = "content://com.android.settings.slices/action/flashlight";
         final List<ContextualCard> cards = new ArrayList<>();
         cards.add(new ConditionalContextualCard.Builder().build());
-        cards.add(buildContextualCard(sliceUri));
+        cards.add(buildContextualCard(TEST_SLICE_URI));
 
         final List<ContextualCard> sortedCards = mManager.sortCards(cards);
 
@@ -58,6 +69,21 @@ public class ContextualCardManagerTest {
                 .isEqualTo(ContextualCard.CardType.CONDITIONAL);
     }
 
+    @Test
+    public void onContextualCardUpdated_emtpyMapWithExistingCards_shouldOnlyKeepConditionalCard() {
+        mManager.mContextualCards.add(new ConditionalContextualCard.Builder().build());
+        mManager.mContextualCards.add(
+                buildContextualCard(TEST_SLICE_URI));
+        mManager.setListener(mListener);
+
+        //Simulate database returns no contents.
+        mManager.onContextualCardUpdated(new ArrayMap<>());
+
+        assertThat(mManager.mContextualCards).hasSize(1);
+        assertThat(mManager.mContextualCards.get(0).getCardType())
+                .isEqualTo(ContextualCard.CardType.CONDITIONAL);
+    }
+
     private ContextualCard buildContextualCard(String sliceUri) {
         return new ContextualCard.Builder()
                 .setName("test_name")