added low battery message

src/systemtask/Messages.h

@@ -29,6 +29,7 @@ namespace Pinetime {
       StopRinging,
       MeasureBatteryTimerExpired,
       BatteryPercentageUpdated,
+      LowBattery,
       StartFileTransfer,
       StopFileTransfer,
       BleRadioEnableToggle

src/systemtask/SystemTask.cpp

@@ -424,6 +424,17 @@ void SystemTask::Work() {
         case Messages::BatteryPercentageUpdated:
           nimbleController.NotifyBatteryLevel(batteryController.PercentRemaining());
           break;
+        case Messages::LowBattery:
+          {
+            Pinetime::Controllers::NotificationManager::Notification notif;
+            std::array<char, 101> message {"Low Battery\0Low Battery\0"};
+            notif.message = message; 
+            notif.size = 25;
+            notif.category = Pinetime::Controllers::NotificationManager::Categories::SimpleAlert;
+            notificationManager.Push(std::move(notif));
+            PushMessage(Messages::OnNewNotification);
+          }
+          break;
         case Messages::OnPairing:
           if (state == SystemTaskState::Sleeping) {
             GoToRunning();