fix(android): restore local notifications after device reboot

android/capacitor/src/main/AndroidManifest.xml

@@ -14,5 +14,15 @@
                 <action android:name="com.google.firebase.MESSAGING_EVENT" />
             </intent-filter>
         </service>
+        <receiver android:name="com.getcapacitor.plugin.notification.LocalNotificationRestoreReceiver" android:directBootAware="true" android:exported="false">
+            <intent-filter>
+                <action android:name="android.intent.action.LOCKED_BOOT_COMPLETED"/>
+                <action android:name="android.intent.action.BOOT_COMPLETED"/>
+                <action android:name="android.intent.action.QUICKBOOT_POWERON" />
+            </intent-filter>
+        </receiver>
     </application>
+
+    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>
+    <uses-permission android:name="android.permission.WAKE_LOCK"/>
 </manifest>

android/capacitor/src/main/java/com/getcapacitor/plugin/LocalNotifications.java

@@ -74,7 +74,7 @@ public void schedule(PluginCall call) {
     }
     JSONArray ids = manager.schedule(call, localNotifications);
     if (ids != null) {
-      notificationStorage.appendNotificationIds(localNotifications);
+      notificationStorage.appendNotifications(localNotifications);
       JSObject result = new JSObject();
       JSArray jsArray = new JSArray();
       for (int i=0; i < ids.length(); i++) {

android/capacitor/src/main/java/com/getcapacitor/plugin/notification/LocalNotification.java

@@ -186,31 +186,37 @@ public static List<LocalNotification> buildNotificationList(PluginCall call) {
         call.error("Invalid JSON object sent to NotificationPlugin", e);
         return null;
       }
-      LocalNotification activeLocalNotification = new LocalNotification();
-      activeLocalNotification.setSource(notification.toString());
-      activeLocalNotification.setId(notification.getInteger("id"));
-      activeLocalNotification.setBody(notification.getString("body"));
-      activeLocalNotification.setActionTypeId(notification.getString("actionTypeId"));
-      activeLocalNotification.setGroup(notification.getString("group"));
-      activeLocalNotification.setSound(notification.getString("sound"));
-      activeLocalNotification.setTitle(notification.getString("title"));
-      activeLocalNotification.setSmallIcon(notification.getString("smallIcon"));
-      activeLocalNotification.setIconColor(notification.getString("iconColor"));
-      activeLocalNotification.setAttachments(LocalNotificationAttachment.getAttachments(notification));
-      activeLocalNotification.setGroupSummary(notification.getBoolean("groupSummary", false));
-      activeLocalNotification.setChannelId(notification.getString("channelId"));
+
       try {
-        activeLocalNotification.setSchedule(new LocalNotificationSchedule(notification));
+          LocalNotification activeLocalNotification = buildNotificationFromJSObject(notification);
+          resultLocalNotifications.add(activeLocalNotification);
       } catch (ParseException e) {
         call.error("Invalid date format sent to Notification plugin", e);
         return null;
       }
-      activeLocalNotification.setExtra(notification.getJSObject("extra"));
-      resultLocalNotifications.add(activeLocalNotification);
     }
     return resultLocalNotifications;
   }
 
+  public static LocalNotification buildNotificationFromJSObject(JSObject jsonObject) throws ParseException {
+      LocalNotification localNotification = new LocalNotification();
+      localNotification.setSource(jsonObject.toString());
+      localNotification.setId(jsonObject.getInteger("id"));
+      localNotification.setBody(jsonObject.getString("body"));
+      localNotification.setActionTypeId(jsonObject.getString("actionTypeId"));
+      localNotification.setGroup(jsonObject.getString("group"));
+      localNotification.setSound(jsonObject.getString("sound"));
+      localNotification.setTitle(jsonObject.getString("title"));
+      localNotification.setSmallIcon(jsonObject.getString("smallIcon"));
+      localNotification.setIconColor(jsonObject.getString("iconColor"));
+      localNotification.setAttachments(LocalNotificationAttachment.getAttachments(jsonObject));
+      localNotification.setGroupSummary(jsonObject.getBoolean("groupSummary", false));
+      localNotification.setChannelId(jsonObject.getString("channelId"));
+      localNotification.setSchedule(new LocalNotificationSchedule(jsonObject));
+      localNotification.setExtra(jsonObject.getJSObject("extra"));
+
+      return localNotification;
+  }
 
   public static List<Integer> getLocalNotificationPendingList(PluginCall call) {
     List<JSONObject> notifications = null;

android/capacitor/src/main/java/com/getcapacitor/plugin/notification/LocalNotificationManager.java

@@ -137,13 +137,17 @@ public JSONArray schedule(PluginCall call, List<LocalNotification> localNotifica
 
     boolean notificationsEnabled = notificationManager.areNotificationsEnabled();
     if (!notificationsEnabled) {
-      call.error("Notifications not enabled on this device");
+      if(call != null){
+        call.error("Notifications not enabled on this device");
+      }
       return null;
     }
     for (LocalNotification localNotification : localNotifications) {
       Integer id = localNotification.getId();
       if (localNotification.getId() == null) {
-        call.error("LocalNotification missing identifier");
+        if(call != null) {
+          call.error("LocalNotification missing identifier");
+        }
         return null;
       }
       dismissVisibleNotification(id);
@@ -214,7 +218,9 @@ private void buildNotification(NotificationManagerCompat notificationManager, Lo
       try {
         mBuilder.setColor(Color.parseColor(iconColor));
       } catch (IllegalArgumentException ex) {
-        call.error("Invalid color provided. Must be a hex string (ex: #ff0000");
+        if(call != null) {
+            call.error("Invalid color provided. Must be a hex string (ex: #ff0000");
+        }
         return;
       }
     }
@@ -294,7 +300,6 @@ private Intent buildIntent(LocalNotification localNotification, String action) {
    * on a certain date "shape" (such as every first of the month)
    */
   // TODO support different AlarmManager.RTC modes depending on priority
-  // TODO restore alarm on device shutdown (requires persistence)
   private void triggerScheduledNotification(Notification notification, LocalNotification request) {
     AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
     LocalNotificationSchedule schedule = request.getSchedule();

android/capacitor/src/main/java/com/getcapacitor/plugin/notification/LocalNotificationRestoreReceiver.java

@@ -0,0 +1,60 @@
+package com.getcapacitor.plugin.notification;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.os.UserManager;
+
+import com.getcapacitor.CapConfig;
+
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.List;
+
+import static android.os.Build.VERSION.SDK_INT;
+
+public class LocalNotificationRestoreReceiver extends BroadcastReceiver {
+
+    @Override
+    public void onReceive(Context context, Intent intent) {
+        if (SDK_INT >= 24) {
+            UserManager um = context.getSystemService(UserManager.class);
+            if (um == null || !um.isUserUnlocked()) return;
+        }
+
+        NotificationStorage storage = new NotificationStorage(context);
+        List<String> ids = storage.getSavedNotificationIds();
+
+        ArrayList<LocalNotification> notifications = new ArrayList<>(ids.size());
+        ArrayList<LocalNotification> updatedNotifications = new ArrayList<>();
+        for (String id : ids) {
+            LocalNotification notification = storage.getSavedNotification(id);
+            if(notification == null) {
+                continue;
+            }
+
+            LocalNotificationSchedule schedule = notification.getSchedule();
+            if(schedule != null) {
+                Date at = schedule.getAt();
+                if(at != null && at.before(new Date())) {
+                    // modify the scheduled date in order to show notifications that would have been delivered while device was off.
+                    long newDateTime = new Date().getTime() + 15 * 1000;
+                    schedule.setAt(new Date(newDateTime));
+                    notification.setSchedule(schedule);
+                    updatedNotifications.add(notification);
+                }
+            }
+
+            notifications.add(notification);
+        }
+
+        if(updatedNotifications.size() > 0){
+            storage.appendNotifications(updatedNotifications);
+        }
+
+        CapConfig config = new CapConfig(context.getAssets(), null);
+        LocalNotificationManager localNotificationManager = new LocalNotificationManager(storage, null, context, config);
+
+        localNotificationManager.schedule(null, notifications);
+    }
+}

android/capacitor/src/main/java/com/getcapacitor/plugin/notification/NotificationStorage.java

@@ -3,7 +3,14 @@
 import android.content.Context;
 import android.content.SharedPreferences;
 
+import com.getcapacitor.JSObject;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import java.text.ParseException;
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.Date;
 import java.util.List;
 import java.util.Map;
@@ -31,13 +38,12 @@ public NotificationStorage(Context context) {
   /**
    * Persist the id of currently scheduled notification
    */
-  public void appendNotificationIds(List<LocalNotification> localNotifications) {
+  public void appendNotifications(List<LocalNotification> localNotifications) {
     SharedPreferences storage = getStorage(NOTIFICATION_STORE_ID);
     SharedPreferences.Editor editor = storage.edit();
-    long creationTime = new Date().getTime();
     for (LocalNotification request : localNotifications) {
       String key = request.getId().toString();
-      editor.putLong(key, creationTime);
+      editor.putString(key, request.getSource());
     }
     editor.apply();
   }
@@ -51,6 +57,40 @@ public List<String> getSavedNotificationIds() {
     return new ArrayList<>();
   }
 
+  public JSObject getSavedNotificationAsJSObject(String key) {
+    SharedPreferences storage = getStorage(NOTIFICATION_STORE_ID);
+    String notificationString = storage.getString(key, null);
+
+    if(notificationString == null){
+        return null;
+    }
+
+    JSObject jsNotification;
+    try {
+        jsNotification  = new JSObject(notificationString);
+    } catch (JSONException ex) {
+        return  null;
+    }
+
+    return jsNotification;
+  }
+
+  public LocalNotification getSavedNotification(String key) {
+    JSObject jsNotification = getSavedNotificationAsJSObject(key);
+    if(jsNotification == null) {
+        return null;
+    }
+
+    LocalNotification notification;
+    try {
+       notification = LocalNotification.buildNotificationFromJSObject(jsNotification);
+    } catch (ParseException ex) {
+       return  null;
+    }
+
+    return  notification;
+  }
+
   /**
    * Remove the stored notifications
    */