Move SuggestionService AIDL related calls to a controller.

The controller makes it easier to manage IPCs and make it easier for
testing.

Bug: 65065268
Test: robotests
Change-Id: Ie5797655543cb22d8196267058598a1b4222a8d1

src/com/android/settings/dashboard/suggestions/SuggestionController.java

@@ -0,0 +1,146 @@
+/*
+ * 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.dashboard.suggestions;
+
+import android.content.ComponentName;
+import android.content.Context;
+import android.content.Intent;
+import android.content.ServiceConnection;
+import android.os.IBinder;
+import android.os.RemoteException;
+import android.service.settings.suggestions.ISuggestionService;
+import android.service.settings.suggestions.Suggestion;
+import android.support.annotation.Nullable;
+import android.support.annotation.WorkerThread;
+import android.util.Log;
+
+import java.util.List;
+
+/**
+ * A controller class to access suggestion data.
+ */
+public class SuggestionController {
+
+    /**
+     * Callback interface when service is connected/disconnected.
+     */
+    public interface ServiceConnectionListener {
+        /**
+         * Called when service is connected.
+         */
+        void onServiceConnected();
+
+        /**
+         * Called when service is disconnected.
+         */
+        void onServiceDisconnected();
+    }
+
+    private static final String TAG = "SuggestionController";
+    private static final boolean DEBUG = false;
+
+    private final Context mContext;
+    private final Intent mServiceIntent;
+
+    private ServiceConnection mServiceConnection;
+    private ISuggestionService mRemoteService;
+    private ServiceConnectionListener mConnectionListener;
+
+    /**
+     * Create a new controller instance.
+     *
+     * @param context  caller context
+     * @param service  The component name for service.
+     * @param listener listener to receive service connected/disconnected event.
+     */
+    public SuggestionController(Context context, ComponentName service,
+            ServiceConnectionListener listener) {
+        mContext = context.getApplicationContext();
+        mConnectionListener = listener;
+        mServiceIntent = new Intent().setComponent(service);
+        mServiceConnection = createServiceConnection();
+    }
+
+    /**
+     * Start the controller.
+     */
+    public void start() {
+        mContext.bindServiceAsUser(mServiceIntent, mServiceConnection, Context.BIND_AUTO_CREATE,
+                android.os.Process.myUserHandle());
+    }
+
+    /**
+     * Stop the controller.
+     */
+    public void stop() {
+        if (mRemoteService != null) {
+            mRemoteService = null;
+            mContext.unbindService(mServiceConnection);
+        }
+    }
+
+    /**
+     * Get setting suggestions.
+     */
+    @Nullable
+    @WorkerThread
+    public List<Suggestion> getSuggestions() {
+        if (!isReady()) {
+            return null;
+        }
+        try {
+            return mRemoteService.getSuggestions();
+        } catch (RemoteException e) {
+            Log.w(TAG, "Error when calling getSuggestion()", e);
+            return null;
+        }
+    }
+
+    /**
+     * Whether or not the manager is ready
+     */
+    private boolean isReady() {
+        return mRemoteService != null;
+    }
+
+    /**
+     * Create a new {@link ServiceConnection} object to handle service connect/disconnect event.
+     */
+    private ServiceConnection createServiceConnection() {
+        return new ServiceConnection() {
+
+            @Override
+            public void onServiceConnected(ComponentName name, IBinder service) {
+                if (DEBUG) {
+                    Log.d(TAG, "Service is connected");
+                }
+                mRemoteService = ISuggestionService.Stub.asInterface(service);
+                if (mConnectionListener != null) {
+                    mConnectionListener.onServiceConnected();
+                }
+            }
+
+            @Override
+            public void onServiceDisconnected(ComponentName name) {
+                if (mConnectionListener != null) {
+                    mRemoteService = null;
+                    mConnectionListener.onServiceDisconnected();
+                }
+            }
+        };
+    }
+}