Allow listeners to fetch current notifications by key.

Bug: 16574195
Change-Id: I269dbcc7fc8912d84229f6a3d950b0015625ae7a

api/current.txt

@@ -27319,6 +27319,7 @@ package android.service.notification {
     method public final void cancelNotification(java.lang.String);
     method public final void cancelNotifications(java.lang.String[]);
     method public android.service.notification.StatusBarNotification[] getActiveNotifications();
+    method public android.service.notification.StatusBarNotification[] getActiveNotifications(java.lang.String[]);
     method public final int getCurrentListenerHints();
     method public android.service.notification.NotificationListenerService.RankingMap getCurrentRanking();
     method public android.os.IBinder onBind(android.content.Intent);

core/java/android/app/INotificationManager.aidl

@@ -58,7 +58,7 @@ interface INotificationManager
     void cancelNotificationFromListener(in INotificationListener token, String pkg, String tag, int id);
     void cancelNotificationsFromListener(in INotificationListener token, in String[] keys);
 
-    ParceledListSlice getActiveNotificationsFromListener(in INotificationListener token);
+    ParceledListSlice getActiveNotificationsFromListener(in INotificationListener token, in String[] keys);
     void requestHintsFromListener(in INotificationListener token, int hints);
     int getHintsFromListener(in INotificationListener token);
 
@@ -71,4 +71,4 @@ interface INotificationManager
     oneway void setZenModeCondition(in Condition condition);
     oneway void setAutomaticZenModeConditions(in Uri[] conditionIds);
     Condition[] getAutomaticZenModeConditions();
-}
+}

core/java/android/service/notification/NotificationListenerService.java

@@ -307,10 +307,22 @@ public abstract class NotificationListenerService extends Service {
      * @return An array of active notifications, sorted in natural order.
      */
     public StatusBarNotification[] getActiveNotifications() {
+        return getActiveNotifications(null);
+    }
+
+    /**
+     * Request one or more notifications by key. Useful if you have been keeping track of
+     * notifications but didn't want to retain the bits, and now need to go back and extract
+     * more data out of those notifications.
+     *
+     * @return An array of notifications corresponding to the requested keys, in the
+     * same order as the key list.
+     */
+    public StatusBarNotification[] getActiveNotifications(String[] keys) {
         if (!isBound()) return null;
         try {
             ParceledListSlice<StatusBarNotification> parceledList =
-                    getNotificationInterface().getActiveNotificationsFromListener(mWrapper);
+                    getNotificationInterface().getActiveNotificationsFromListener(mWrapper, keys);
             List<StatusBarNotification> list = parceledList.getList();
 
             int N = list.size();

services/core/java/com/android/server/notification/NotificationManagerService.java

@@ -1277,21 +1277,29 @@ public class NotificationManagerService extends SystemService {
          * should be used.
          *
          * @param token The binder for the listener, to check that the caller is allowed
+         * @param keys An array of notification keys to fetch, or null to fetch everything
          * @returns The return value will contain the notifications specified in keys, in that
          *      order, or if keys is null, all the notifications, in natural order.
          */
         @Override
         public ParceledListSlice<StatusBarNotification> getActiveNotificationsFromListener(
-                INotificationListener token) {
+                INotificationListener token, String[] keys) {
             synchronized (mNotificationList) {
                 final ManagedServiceInfo info = mListeners.checkServiceTokenLocked(token);
                 final ArrayList<StatusBarNotification> list
                         = new ArrayList<StatusBarNotification>();
-                final int N = mNotificationList.size();
+                final boolean getKeys = keys != null;
+                final int N = getKeys ? keys.length : mNotificationList.size();
+                list.ensureCapacity(N);
                 for (int i=0; i<N; i++) {
-                    StatusBarNotification sbn = mNotificationList.get(i).sbn;
-                    if (isVisibleToListener(sbn, info)) {
-                        list.add(sbn);
+                    final NotificationRecord r = getKeys
+                            ? mNotificationsByKey.get(keys[i])
+                            : mNotificationList.get(i);
+                    if (r != null) {
+                        StatusBarNotification sbn = r.sbn;
+                        if (isVisibleToListener(sbn, info)) {
+                            list.add(sbn);
+                        }
                     }
                 }
                 return new ParceledListSlice<StatusBarNotification>(list);