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Тема: Что мне нужно сделать, чтобы «наследовать» _flDetailData от EventBloc

Два файла, перечисленные ниже LineChartEvents и EventBloc, настроены для отображения линейного графика fl_charts. LineChartEvents-это страница отображения, и она предназначена для получения данных из подпрограммы getChartData()блока событий

Страница LineChartEvents отображает линейную диаграмму с использованием данных, хранящихся в List _flDetailData, после выполнения

 ChartData(  startDate: '1638700000000',  endDate: '2638700000000', ).getChartData();  

в init() — но он всегда пуст.

Подпрограмма EventBloc getChartData() успешно извлекает данные из firestore и заполняет список _flDetailData внутри EventBloc точками FLSPOT.

Этот код выполняется, но _flDetailData пуст, когда я пытаюсь использовать его в build().

Пожалуйста, помогите

Доброе утро, день или вечер и с наилучшими пожеланиями,

Джаз

Спасибо

PS: у меня нет сервера для ссылки, поэтому код находится в строке ниже

======================= События линейного графика ========================

 import 'package:cloud_firestore/cloud_firestore.dart'; import 'package:fl_chart/fl_chart.dart'; import 'package:flutter/material.dart'; import 'package:se_app/blocs/event_rollup_bloc.dart'; import 'package:provider/provider.dart'; import 'package:se_app/pages/charts/chart_data.dart'; import 'package:shared_preferences/shared_preferences.dart'; import 'package:se_app/pages/charts/chart_data';  class LineChartEvents extends StatefulWidget {  const LineChartEvents({Key? key}) : super(key: key);   @override  _LineChartEventsState createState() =gt; _LineChartEventsState(); }  class _LineChartEventsState extends Statelt;LineChartEventsgt; {  Listlt;Colorgt; gradientColors = [  const Color(0xff23b6e6),  const Color(0xff02d39a),  ];   List _data = [];  Listlt;FlSpotgt; flData = [];  int index = 0;  int _duration = 0;  String _eventTitle = '';  int _timestampInt = 0;  String _timestampIntStr = '';  String _dateNowStr = '';  Timestamp _timestamp = Timestamp.now();  int _day = 0;  int _month = 0;  int _year = 0;  int _hour = 0;  int _minute = 0;  int _seconds = 0;   Listlt;FlSpotgt; _flDetailData = [];   @override  initState() {  super.initState();  ChartData(  startDate: '1638700000000',  endDate: '2638700000000',  ).getChartData();  }   bool showAvg = false;   Future _getDate() async {  final DateTime _nowDT = DateTime.now();  _timestamp = Timestamp.now();  _timestampInt = Timestamp.now().millisecondsSinceEpoch;  _timestampIntStr = _timestampInt.toString().substring(0, 13);  final dateStrSegments = _dateNowStr.split('-');  if (dateStrSegments.length == 6) {  _year = int.tryParse(dateStrSegments[0])!;  _month = int.tryParse(dateStrSegments[1])!;  _day = int.tryParse(dateStrSegments[2])!;  _hour = int.tryParse(dateStrSegments[3])!;  _minute = int.tryParse(dateStrSegments[4])!;  _seconds = int.tryParse(dateStrSegments[5])!;  }  }   Duration swapAnimationDuration = const Duration(milliseconds: 150);  Curve swapAnimationCurve = Curves.linear;   @override  Widget build(BuildContext context) {  double w = MediaQuery.of(context).size.width;  double h = MediaQuery.of(context).size.height;   return Container(  color: Colors.blueGrey,  child: Flex(  direction: Axis.vertical,  children: [  Container(  color: Colors.blueGrey,  width: w * .6,  height: 42,  child: ElevatedButton(  style: ElevatedButton.styleFrom(  elevation: 8,  primary:  showAvg ? Colors.black : Colors.white.withOpacity(0.5)),  onPressed: () {  setState(() {  showAvg = !showAvg;  });  },  child: Text(  showAvg ? 'Per Day Average' : 'Per Day Detail',  style: TextStyle(  fontSize: 24,  color:  showAvg ? Colors.white.withOpacity(0.5) : Colors.black),  ),  ),  ),  AspectRatio(  aspectRatio: 1.70,  child: Container(  height: 120,  decoration: const BoxDecoration(  borderRadius: BorderRadius.all(  Radius.circular(18),  ),  color: Color(0xff232d37)),  child: Padding(  padding: const EdgeInsets.only(  right: 18.0, left: 12.0, top: 12, bottom: 12),  child: LineChart(  showAvg ? avgData(_flDetailData) : mainData(_flDetailData),  ),  ),  ),  ),  ],  ),  );  }   LineChartData mainData(flDetailData) {  final EventRollupBloc eventRollupBloc =  Provider.oflt;EventRollupBlocgt;(context);  eventRollupBloc.getChartSeries(10, Timestamp(10000000, 1000000), 200, 20);  return LineChartData(  gridData: FlGridData(  show: true,  drawVerticalLine: true,  getDrawingHorizontalLine: (value) {  return FlLine(  color: const Color(0xff37434d),  strokeWidth: 1,  );  },  getDrawingVerticalLine: (value) {  return FlLine(  color: const Color(0xff37434d),  strokeWidth: 1,  );  },  ),  titlesData: FlTitlesData(  show: true,  rightTitles: SideTitles(showTitles: false),  topTitles: SideTitles(showTitles: true),  bottomTitles: SideTitles(  showTitles: true,  reservedSize: 22,  interval: 1,  getTextStyles: (context, value) =gt; const TextStyle(  color: Color(0xff68737d),  fontWeight: FontWeight.bold,  fontSize: 16),  getTitles: (value) {  switch (value.toInt()) {  case 2:  return 'MAR';  case 5:  return 'JUN';  case 8:  return 'SEP';  }  return '';  },  margin: 8,  ),  leftTitles: SideTitles(  showTitles: true,  interval: 1,  getTextStyles: (context, value) =gt; const TextStyle(  color: Color(0xff67727d),  fontWeight: FontWeight.bold,  fontSize: 15,  ),  getTitles: (value) {  switch (value.toInt()) {  case 1:  return '10';  case 3:  return '30';  case 5:  return '50';  }  return '';  },  reservedSize: 32,  margin: 12,  ),  ),  borderData: FlBorderData(  show: true,  border: Border.all(color: const Color(0xff37434d), width: 1),  ),  minX: 0,  maxX: 20,  minY: 0,  maxY: 20,  lineBarsData: [  LineChartBarData(  spots: _flDetailData,  // const [  // FlSpot(0, 3),  // FlSpot(2.6, 2),  // FlSpot(4.9, 5),  // FlSpot(6.8, 3.1),  // FlSpot(8, 4),  // FlSpot(9.5, 3),  // FlSpot(11, 4),  // ],  isCurved: true,  colors: gradientColors,  barWidth: 5,  isStrokeCapRound: true,  dotData: FlDotData(  show: false,  ),  belowBarData: BarAreaData(  show: true,  colors:  gradientColors.map((color) =gt; color.withOpacity(0.3)).toList(),  ),  ),  ],  );  }   LineChartData avgData(flDetailData) {  return LineChartData(  lineTouchData: LineTouchData(enabled: false),  gridData: FlGridData(  show: true,  drawHorizontalLine: true,  getDrawingVerticalLine: (value) {  return FlLine(  color: const Color(0xff37434d),  strokeWidth: 1,  );  },  getDrawingHorizontalLine: (value) {  return FlLine(  color: const Color(0xff37434d),  strokeWidth: 1,  );  },  ),  titlesData: FlTitlesData(  show: true,  bottomTitles: SideTitles(  showTitles: true,  reservedSize: 22,  getTextStyles: (context, value) =gt; const TextStyle(  color: Color(0xff68737d),  fontWeight: FontWeight.bold,  fontSize: 16),  getTitles: (value) {  switch (value.toInt()) {  case 2:  return 'MAR';  case 5:  return 'JUN';  case 8:  return 'SEP';  }  return '';  },  margin: 8,  interval: 1,  ),  leftTitles: SideTitles(  showTitles: true,  getTextStyles: (context, value) =gt; const TextStyle(  color: Color(0xff67727d),  fontWeight: FontWeight.bold,  fontSize: 15,  ),  getTitles: (value) {  switch (value.toInt()) {  case 1:  return '10k';  case 3:  return '30k';  case 5:  return '50k';  }  return '';  },  reservedSize: 32,  interval: 1,  margin: 12,  ),  topTitles: SideTitles(showTitles: false),  rightTitles: SideTitles(showTitles: false),  ),  borderData: FlBorderData(  show: true,  border: Border.all(color: const Color(0xff37434d), width: 1)),  minX: 0,  maxX: 11,  minY: 0,  maxY: 6,  lineBarsData: [  LineChartBarData(  spots: const [  FlSpot(0, 3.44),  FlSpot(2.6, 3.44),  FlSpot(4.9, 3.44),  FlSpot(6.8, 3.44),  FlSpot(8, 3.44),  FlSpot(9.5, 3.44),  FlSpot(11, 3.44),  ],  isCurved: true,  colors: [  ColorTween(begin: gradientColors[0], end: gradientColors[1])  .lerp(0.2)!,  ColorTween(begin: gradientColors[0], end: gradientColors[1])  .lerp(0.2)!,  ],  barWidth: 5,  isStrokeCapRound: true,  dotData: FlDotData(  show: false,  ),  belowBarData: BarAreaData(show: true, colors: [  ColorTween(begin: gradientColors[0], end: gradientColors[1])  .lerp(0.2)!  .withOpacity(0.1),  ColorTween(begin: gradientColors[0], end: gradientColors[1])  .lerp(0.2)!  .withOpacity(0.1),  ]),  ),  ],  );  } }  

=========================================================

====================== EventBloc ========================

 import 'package:charts_flutter/flutter.dart' as charts; import 'package:cloud_firestore/cloud_firestore.dart'; import 'package:flutter/cupertino.dart'; import 'package:flutter/material.dart'; import 'package:intl/intl.dart'; import 'package:se_app/blocs/profile_bloc.dart'; import 'package:se_app/models/charting_data.dart'; import 'package:shared_preferences/shared_preferences.dart'; // import 'package:fl_chart/fl_chart.dart';  class EventBloc extends ChangeNotifier {  init() {  // getEventLength();  getData();  }   EventBloc() {  // getEventLength();  getData();  }   String data = '';  String _date = '';   String get date =gt; _date;  List _data = [];   List get eventData =gt; _data;  List _filteredData = [];   List get filteredData =gt; _filteredData;  bool _hasData = false;   bool get hasData =gt; _hasData;   int _lastEventTimestampInt = 0;  String _lastEventType = '';  Timestamp _timestamp = Timestamp.now();  int _stopTimestampInt = 0;  int _timestampNowInt = 0;  int _eventDurationInt = 0;  String _durationDateStr = '';  String _timestampNowIntStr = '';  String _stopTimestampStr = '';  int _startEventTS = 0;  int _stopEventTS = 0;  String _eventDurationStr = '';   // bool _emoBool = false;   // charting series vars  Listlt;charts.Seriesgt; seriesList = [];  bool animate = false;  int _duration = 0;  int _idx = 0;  int _upperRangeTS = 0;  int _lowerRangeTS = 0;  DateTime _upperRangeDT = DateTime.now();  DateTime _lowerRangeDT = DateTime.now();  int _day = 0;  int _month = 0;  int _year = 0;  int _hour = 0;  int _minute = 0;  int _seconds = 0;  String _eventType = 'Ready';  String _uid = '';  String _dateStrDDMMYYYYHHMMSS = 'DDMMYYYYHHMMSS';  String sessionDuration = '';  int sessionCost = 0;  int _eventLength = 0;  int get eventLength =gt; _eventLength;  int _savedNlength = 0;  int get savedNlength =gt; _savedNlength;  int _eventFinalLength = 0;  int get eventFinalLength =gt; _eventFinalLength;   Future getData() async {  // TODO: JME #1 -  final SharedPreferences _sp = await SharedPreferences.getInstance();  _uid = _sp.getString('uid')!;  // setEventDurationString();  QuerySnapshot snap = await FirebaseFirestore.instance  .collection('event')  .where("uid", isEqualTo: _uid)  .orderBy("timestamp", descending: false)  .limit(1000)  .get();  var x = snap.docs;  _data.clear();  for (var f in x) {  _data.add(f);  }  // _data.sort((a, b) =gt; a['timestamp'].compareTo(b['timestamp']));  notifyListeners();  }   Future saveData(eventType, time) async {  // TODO: JME #1 -  SharedPreferences sp = await SharedPreferences.getInstance();  String? _uid = sp.getString('uid');  final ProfileBloc pb = ProfileBloc();   _timestampNowInt = Timestamp.now().millisecondsSinceEpoch;  _timestampNowIntStr = _timestampNowInt.toString();   await FirebaseFirestore.instance.collection('event').doc().set(  {  "uid": _uid,  "timestamp": _timestampNowIntStr,  "year": _year,  "month": _month,  "day": _day,  "hour": _hour,  "minute": _minute,  "seconds": _seconds,  "eventType": eventType  },  SetOptions(merge: false),  );   // _emoBool = eventType.toString().substring(0, 3) == 'Emo';   if (eventType == 'Live' || eventType == 'Smoke') {  //TODO: JME EMO amp;amp; _emoBool != true) {  _lastEventTimestampInt = _timestampNowInt;  _lastEventType = eventType;  }   if (eventType == 'Stop' || eventType == 'Complete') {  //TODO: JME Emo - || _emoBool} {  setEventDurationString();  await FirebaseFirestore.instance.collection('eventRollup').doc().set(  {  "uid": _uid,  "timestamp": _timestampNowIntStr,  // "duration": _emoBool ? '0' : _eventDurationStr,  "duration": _eventDurationStr,  "year": _year,  "month": _month,  "day": _day,  "hour": _hour,  "minute": _minute,  "seconds": _seconds,  // "eventType": _emoBool ? eventType : _lastEventType  "eventType": _lastEventType  },  SetOptions(merge: false),  );  // .then(  // //TODO: JME #1 (value) =gt; {pb.saveStatistics()},  // );  // set eventTypes to current event  // _eventType = '';  // _lastEventType = '';  // _lastEventTimestampInt = 0;  }   // getData();  }   Future setEventDurationString() async {  // _eventDurationStr = _duration.toString();  _stopTimestampInt = Timestamp.now().millisecondsSinceEpoch;  _eventDurationInt = _timestampNowInt - _lastEventTimestampInt;  String aStr = DateFormat('yyyy-mm-dd-hh-mm-ssmmm')  .format(DateTime.fromMillisecondsSinceEpoch(_eventDurationInt));  _eventDurationStr = _eventDurationInt.toString();   // split out date segments toInts for storage  // reason is to speed up queries for charting  // by day month and year  final dateStrSegments = aStr.split('-');  if (dateStrSegments.length == 6) {  _year = int.tryParse(dateStrSegments[0])!;  _month = int.tryParse(dateStrSegments[1])!   1;  _day = int.tryParse(dateStrSegments[2])!;  _hour = int.tryParse(dateStrSegments[3])!;  _minute = int.tryParse(dateStrSegments[4])!;  _seconds = int.tryParse(dateStrSegments[5].substring(0, 2))!;  // }  }   Future deleteEvent(uid, timestamp) async {  FirebaseFirestore.instance  .collection('event/$timestamp')  .doc('$uid$timestamp')  .delete();  getData();  }   //charting routines   void setRange(_startTimestamp, _duration, _period) {  // Timestamp _ts = Timestamp.now();  int _tsInt = Timestamp.now().millisecondsSinceEpoch;  String _tsStr = Timestamp.now().toString();  DateTime _tsDate = Timestamp.now().toDate();  var now = DateTime.now();  var _lowerRange =  now.subtract(Duration(days: chartPeriodDays[_idx] * _duration));  int _durMS = chartPeriod[_idx] * _duration;  _upperRangeTS = _tsInt;  }   Future getChartSeries(  _period, _startTimestamp, _duration, _pagingListSize) async {  if (chartPeriod.contains(_period)) {  _idx = chartPeriod.indexOf(_period);  setRange(_startTimestamp, _duration, _period);  } else {  //TODO: implement custom range  // return default _period of a week in 7 stacks  _period = 'Week';  _idx = 2;  _duration = 1;  _pagingListSize = 100;  setRange(_startTimestamp, _duration, _period);  }   // get user uid  SharedPreferences sp = await SharedPreferences.getInstance();  String? _uid = sp.getString('uid');   // get data gt;=lt; range  // setEventDurationString();  QuerySnapshot snap = await FirebaseFirestore.instance  .collection('event')  .where("uid", isEqualTo: _uid)  .orderBy("timestamp", descending: true)  .get();  var x = snap.docs;  _data.clear();  for (var f in x) {  _data.add(f);  }  // _data.sort((a, b) =gt; b['timestamp'].compareTo(a['timestamp']));  // notifyListeners();  }  } }