Added survey triggering mechanisms

Surveys can now be triggered on a subset of Settings screens.
Surveys can also be modified/created for this subset of
screens remotely.

Test: RoboTests && JUnitTests
Bug: 27823357
Change-Id: I1534af5573bef6f6c65c9c99b6f5a2917c3325b9

src/com/android/settings/core/InstrumentedPreferenceFragment.java

@@ -31,6 +31,7 @@ import com.android.settings.core.instrumentation.VisibilityLoggerMixin;
 import com.android.settings.core.lifecycle.ObservablePreferenceFragment;
 import com.android.settings.overlay.FeatureFactory;
 import com.android.settings.widget.PreferenceDividerDecoration;
+import com.android.settings.survey.SurveyMixin;
 
 /**
  * Instrumented fragment that logs visibility state.
@@ -61,6 +62,7 @@ public abstract class InstrumentedPreferenceFragment extends ObservablePreferenc
     public InstrumentedPreferenceFragment() {
         // Mixin that logs visibility change for activity.
         getLifecycle().addObserver(new VisibilityLoggerMixin(getMetricsCategory()));
+        getLifecycle().addObserver(new SurveyMixin(this, getClass().getSimpleName()));
     }
 
     @Override

src/com/android/settings/overlay/SurveyFeatureProvider.java

@@ -40,16 +40,46 @@ public interface SurveyFeatureProvider {
      *
      * @param activity The host activity to show the survey in.
      * @param surveyId A unique Id representing a survey to download.
+     * @return A boolean indicating if a survey was shown or not.
      */
-    void showSurveyIfAvailable(Activity activity, String surveyId);
+    boolean showSurveyIfAvailable(Activity activity, String surveyId);
 
     /**
      * A helper method to get the surveyId. Implementers should create a mapping of
      * keys to surveyIds and provide them via this function.
      *
      * @param context A valid context.
-     * @param key The key to get the surveyId for.
+     * @param simpleKey The simple name of the key to get the surveyId for.
      * @return The unique Id as a string or null on error.
      */
-    String getSurveyId(Context context, String key);
+    String getSurveyId(Context context, String simpleKey);
+
+    /**
+     * Removes the survey for {@code siteId} if it expired, then returns the expiration date (as a
+     * unix timestamp) for the remaining survey should it exist and be ready to show. Returns -1 if
+     * no valid survey exists after removing the potentially expired one.
+     *
+     * @param context the calling context.
+     * @param surveyId the site ID.
+     * @return the unix timestamp for the available survey for the given {@coe siteId} or -1 if
+     * there is none available.
+     */
+    long getSurveyExpirationDate(Context context, String surveyId);
+
+    /**
+     * Registers an activity to show surveys/prompts as soon as they are downloaded. The receiver
+     * should be unregistered prior to destroying the activity to avoid undefined behavior by
+     * calling {@link #unregisterReceiver(Activity, BroadcastReceiver)}.
+     * @param activity The activity that should show surveys once they are downloaded.
+     * @return the broadcast receiver listening for survey downloads. Must be unregistered before
+     * leaving the activity.
+     */
+    BroadcastReceiver createAndRegisterReceiver(Activity activity);
+
+    /**
+     * Unregisters the broadcast receiver for this activity. Should only be called once per activity
+     * after a call to {@link #createAndRegisterReceiver(Activity)}.
+     * @param activity The activity that was used to register the BroadcastReceiver.
+     */
+    void unregisterReceiver(Activity activity, BroadcastReceiver receiver);
 }

src/com/android/settings/survey/SurveyMixin.java

@@ -0,0 +1,82 @@
+/*
+ * 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.survey;
+
+import android.app.Activity;
+import android.content.BroadcastReceiver;
+import com.android.settings.core.InstrumentedPreferenceFragment;
+import com.android.settings.core.lifecycle.LifecycleObserver;
+import com.android.settings.core.lifecycle.events.OnPause;
+import com.android.settings.core.lifecycle.events.OnResume;
+import com.android.settings.overlay.FeatureFactory;
+import com.android.settings.overlay.SurveyFeatureProvider;
+
+/**
+ * attaches extra, survey related work to the onResume method of registered observable classes
+ * in settings. This allows new classes to automatically support settings provided the extend
+ * one of the relevant classes in com.android.settings.lifecycle.
+ */
+public class SurveyMixin implements LifecycleObserver, OnResume, OnPause {
+
+    private String mName;
+    private InstrumentedPreferenceFragment mFragment;
+    private BroadcastReceiver mReceiver;
+
+    /**
+     * A mixin that attempts to perform survey related tasks right before onResume is called
+     * in a Settings PreferenceFragment. This will allow for remote updating and creation of
+     * surveys.
+     * @param fragment The fragment that this mixin will be attached to.
+     * @param fragmentName The simple name of the fragment.
+     */
+    public SurveyMixin(InstrumentedPreferenceFragment fragment, String fragmentName) {
+        mName = fragmentName;
+        mFragment = fragment;
+    }
+
+    @Override
+    public void onResume() {
+        Activity activity = mFragment.getActivity();
+
+        // guard against the activity not existing yet or the feature being disabled
+        if (activity != null) {
+            SurveyFeatureProvider provider =
+                    FeatureFactory.getFactory(activity).getSurveyFeatureProvider(activity);
+            if (provider != null) {
+
+                // Try to download a survey if there is none available, show the survey otherwise
+                String id = provider.getSurveyId(activity, mName);
+                if (provider.getSurveyExpirationDate(activity, id) <= -1) {
+                    // register the receiver to show the survey on completion.
+                    mReceiver = provider.createAndRegisterReceiver(activity);
+                    provider.downloadSurvey(activity, id, "fakeData");
+                } else {
+                    provider.showSurveyIfAvailable(activity, id);
+                }
+            }
+        }
+    }
+
+    @Override
+    public void onPause() {
+        Activity activity = mFragment.getActivity();
+        if (mReceiver != null && activity != null) {
+            SurveyFeatureProvider provider =
+                    FeatureFactory.getFactory(activity).getSurveyFeatureProvider(activity);
+            provider.unregisterReceiver(activity, mReceiver);
+        }
+    }
+}