Create NetworkScorerPicker preference controller to set preference summary.

Bug: 35854552
Test: make ROBOTEST_FILTER=NetworkScorerPickerPreferenceControllerTest
RunSettingsRoboTests -j40

Change-Id: I6dbd18abd67613ed0f85a52f1a3e13fdab0dca6c

src/com/android/settings/network/NetworkScoreManagerWrapper.java

@@ -56,6 +56,13 @@ public class NetworkScoreManagerWrapper {
         return mNetworkScoreManager.getActiveScorerPackage();
     }
 
+    /**
+     * Returns metadata about the active scorer or <code>null</code> if there is no active scorer.
+     */
+    @Nullable
+    public NetworkScorerAppData getActiveScorer() {
+        return mNetworkScoreManager.getActiveScorer();
+    }
 
     /**
      * Set the active scorer to a new package and clear existing scores.

src/com/android/settings/network/NetworkScorerPickerPreferenceController.java

@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2017 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.network;
+
+import android.content.Context;
+import android.net.NetworkScorerAppData;
+import android.provider.Settings;
+import android.support.v7.preference.Preference;
+import com.android.settings.R;
+import com.android.settings.core.PreferenceController;
+
+/**
+ * {@link PreferenceController} that shows the active network scorer and toggles the preference
+ * based on {@link Settings.Global.NETWORK_RECOMMENDATIONS_ENABLED}.
+ */
+public class NetworkScorerPickerPreferenceController extends PreferenceController {
+
+    private static final String KEY_NETWORK_SCORER_PICKER = "network_scorer_picker";
+
+    private final NetworkScoreManagerWrapper mNetworkScoreManager;
+
+    public NetworkScorerPickerPreferenceController(Context context,
+            NetworkScoreManagerWrapper networkScoreManager) {
+        super(context);
+        mNetworkScoreManager = networkScoreManager;
+    }
+
+    @Override
+    public String getPreferenceKey() {
+        return KEY_NETWORK_SCORER_PICKER;
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        boolean enabled = Settings.Global.getInt(mContext.getContentResolver(),
+                Settings.Global.NETWORK_RECOMMENDATIONS_ENABLED, 0) == 1;
+        preference.setEnabled(enabled);
+        if (!enabled) {
+            preference.setSummary(null);
+            return;
+        }
+
+        NetworkScorerAppData scorer = mNetworkScoreManager.getActiveScorer();
+        if (scorer == null) {
+            preference.setSummary(mContext.getString(
+                    R.string.network_scorer_picker_none_preference));
+        } else {
+            preference.setSummary(scorer.getRecommendationServiceLabel());
+        }
+    }
+
+    @Override
+    public boolean isAvailable() {
+        return true;
+    }
+}