created controller for alarms

lib/service/alarm_controller.dart

@@ -0,0 +1,31 @@
+import 'package:flutter/material.dart';
+
+import '../model/alarm.dart';
+import '../model/repositories/interfaces/alarm_repository.dart';
+
+class AlarmController extends ChangeNotifier {
+  AlarmController(AlarmRepository repository) : _repository = repository {
+    _loadAlarms();
+  }
+
+  final AlarmRepository _repository;
+
+  final List<Alarm> _alarms = [];
+
+  Future<void> addAlarm(Alarm alarm) {
+    _alarms.add(alarm);
+    notifyListeners();
+    return _repository.createAlarm(alarm);
+  }
+
+  Future<void> deleteAlarm(Alarm alarm) {
+    _alarms.remove(alarm);
+    notifyListeners();
+    return _repository.deleteAlarm(alarm);
+  }
+
+  Future<void> _loadAlarms() {
+    _alarms.clear();
+    return _repository.loadAlarms().then((value) => _alarms.addAll(value));
+  }
+}