66 lines
1.5 KiB
Dart
66 lines
1.5 KiB
Dart
import 'dart:async';
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import 'package:flutter/material.dart';
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import 'package:firebase_database/firebase_database.dart';
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import '../models/sensor_model.dart';
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import '../services/firebase_service.dart';
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class SensorProvider extends ChangeNotifier {
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SensorModel? _sensor;
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SensorModel? get sensor => _sensor;
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bool _isLoading = true;
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bool get isLoading => _isLoading;
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String? _errorMessage;
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String? get errorMessage => _errorMessage;
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StreamSubscription<DatabaseEvent>? _subscription;
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void startListening() {
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_subscription?.cancel();
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_isLoading = true;
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_errorMessage = null;
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_subscription = FirebaseService.currentRef.onValue.listen((event) {
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if (event.snapshot.value == null) {
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_sensor = null;
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_isLoading = false;
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notifyListeners();
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return;
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}
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try {
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final data = Map<dynamic, dynamic>.from(event.snapshot.value as Map);
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_sensor = SensorModel.fromMap(data);
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_errorMessage = null;
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} catch (e) {
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_sensor = null;
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_errorMessage = 'Parsing Error: $e';
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}
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_isLoading = false;
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notifyListeners();
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}, onError: (error) {
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_sensor = null;
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_errorMessage = 'Firebase Error: $error';
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_isLoading = false;
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notifyListeners();
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});
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}
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void stopListening() {
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_subscription?.cancel();
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}
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@override
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void dispose() {
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_subscription?.cancel();
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super.dispose();
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}
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}
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