Invoke notifySummaryChanged callback only when text changed.

Bug: 32905374
Test: make -j40 RunSettingsRoboTests
Change-Id: I709329d3024656080723383231a884f3cf8a9a43

src/com/android/settings/dashboard/SummaryLoader.java

@@ -25,6 +25,8 @@ import android.os.HandlerThread;
 import android.os.Looper;
 import android.os.Message;
 import android.os.Process;
+import android.support.annotation.VisibleForTesting;
+import android.text.TextUtils;
 import android.util.ArrayMap;
 import android.util.ArraySet;
 import android.util.Log;
@@ -141,6 +143,20 @@ public class SummaryLoader {
                 if (DEBUG) {
                     Log.d(TAG, "setSummary " + tile.title + " - " + summary);
                 }
+
+                updateSummaryIfNeeded(tile, summary);
+            }
+        });
+    }
+
+    @VisibleForTesting
+    void updateSummaryIfNeeded(Tile tile, CharSequence summary) {
+        if (TextUtils.equals(tile.summary, summary)) {
+            if (DEBUG) {
+                Log.d(TAG, "Summary doesn't change, skipping summary update for " + tile.title);
+            }
+            return;
+        }
         tile.summary = summary;
         if (mSummaryConsumer != null) {
             mSummaryConsumer.notifySummaryChanged(tile);
@@ -151,8 +167,6 @@ public class SummaryLoader {
             }
         }
     }
-        });
-    }
 
     /**
      * Only call from the main thread.

tests/robotests/src/com/android/settings/dashboard/SummaryLoaderTest.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings.dashboard;
+
+import android.app.Activity;
+import com.android.settings.SettingsRobolectricTestRunner;
+import com.android.settings.TestConfig;
+import com.android.settingslib.drawer.DashboardCategory;
+import com.android.settingslib.drawer.Tile;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.Robolectric;
+import org.robolectric.annotation.Config;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import static com.google.common.truth.Truth.assertThat;
+
+@RunWith(SettingsRobolectricTestRunner.class)
+@Config(manifest = TestConfig.MANIFEST_PATH, sdk = TestConfig.SDK_VERSION)
+public class SummaryLoaderTest {
+    private static final String SUMMARY_1 = "summary1";
+    private static final String SUMMARY_2 = "summary2";
+    private SummaryLoader mSummaryLoader;
+    private boolean mCallbackInvoked;
+    private Tile mTile;
+
+    @Before
+    public void SetUp() {
+        mTile = new Tile();
+        mTile.summary = SUMMARY_1;
+        mCallbackInvoked = false;
+
+        final Activity activity = Robolectric.buildActivity(Activity.class).get();
+        final List<DashboardCategory> categories = new ArrayList<>();
+        mSummaryLoader = new SummaryLoader(activity, categories);
+        mSummaryLoader.setSummaryConsumer(new SummaryLoader.SummaryConsumer() {
+            @Override
+            public void notifySummaryChanged(Tile tile) {
+                mCallbackInvoked = true;
+            }
+        });
+    }
+
+    @Test
+    public void testUpdateSummaryIfNeeded_SummaryIdentical_NoCallback() {
+        mSummaryLoader.updateSummaryIfNeeded(mTile, SUMMARY_1);
+
+        assertThat(mCallbackInvoked).isFalse();
+    }
+
+    @Test
+    public void testUpdateSummaryIfNeeded_SummaryChanged_HasCallback() {
+        mSummaryLoader.updateSummaryIfNeeded(mTile, SUMMARY_2);
+
+        assertThat(mCallbackInvoked).isTrue();
+    }
+}