Make contextual card count configurable.

Decide how many card we should show at once on the homepage based on the
value in Settings Global for more flexibility. Fall back to the default
value if there is nothing set up.

Bug: 138754406
Test: robotests
Change-Id: I8d31d98eafb636a5e72af76ffec7e3dae0be3cbc

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

@@ -27,6 +27,7 @@ import android.database.Cursor;
 import android.net.Uri;
 import android.os.Handler;
 import android.os.Looper;
+import android.provider.Settings;
 import android.util.Log;
 
 import androidx.annotation.NonNull;
@@ -50,6 +51,8 @@ public class ContextualCardLoader extends AsyncLoaderCompat<List<ContextualCard>
 
     @VisibleForTesting
     static final int DEFAULT_CARD_COUNT = 3;
+    @VisibleForTesting
+    static final String CONTEXTUAL_CARD_COUNT = "contextual_card_count";
     static final int CARD_CONTENT_LOADER_ID = 1;
 
     private static final String TAG = "ContextualCardLoader";
@@ -130,8 +133,9 @@ public class ContextualCardLoader extends AsyncLoaderCompat<List<ContextualCard>
         final List<ContextualCard> hiddenCards = new ArrayList<>();
 
         final int size = eligibleCards.size();
+        final int cardCount = getCardCount();
         for (int i = 0; i < size; i++) {
-            if (i < DEFAULT_CARD_COUNT) {
+            if (i < cardCount) {
                 visibleCards.add(eligibleCards.get(i));
             } else {
                 hiddenCards.add(eligibleCards.get(i));
@@ -149,6 +153,14 @@ public class ContextualCardLoader extends AsyncLoaderCompat<List<ContextualCard>
         return visibleCards;
     }
 
+    @VisibleForTesting
+    int getCardCount() {
+        // Return the card count if Settings.Global has KEY_CONTEXTUAL_CARD_COUNT key,
+        // otherwise return the default one.
+        return Settings.Global.getInt(mContext.getContentResolver(),
+                CONTEXTUAL_CARD_COUNT, DEFAULT_CARD_COUNT);
+    }
+
     @VisibleForTesting
     Cursor getContextualCardsFromProvider() {
         return CardDatabaseHelper.getInstance(mContext).getContextualCards();

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

@@ -31,6 +31,7 @@ import static org.mockito.Mockito.verify;
 import android.app.settings.SettingsEnums;
 import android.content.Context;
 import android.net.Uri;
+import android.provider.Settings;
 
 import com.android.settings.R;
 import com.android.settings.slices.CustomSliceRegistry;
@@ -110,6 +111,20 @@ public class ContextualCardLoaderTest {
                 eq(SettingsEnums.ACTION_CONTEXTUAL_CARD_NOT_SHOW), any(String.class));
     }
 
+    @Test
+    public void getCardCount_noConfiguredCardCount_returnDefaultCardCount() {
+        assertThat(mContextualCardLoader.getCardCount()).isEqualTo(DEFAULT_CARD_COUNT);
+    }
+
+    @Test
+    public void getCardCount_hasConfiguredCardCount_returnConfiguredCardCount() {
+        int configCount = 4;
+        Settings.Global.putLong(mContext.getContentResolver(),
+                ContextualCardLoader.CONTEXTUAL_CARD_COUNT, configCount);
+
+        assertThat(mContextualCardLoader.getCardCount()).isEqualTo(configCount);
+    }
+
     private List<ContextualCard> getContextualCardList() {
         final List<ContextualCard> cards = new ArrayList<>();
         cards.add(new ContextualCard.Builder()