如何將事件從 API 傳遞到 utils table_calender 中的 _KEventsSource

Question

我正在嘗試遍歷來自 API 的事件並將它們加載到 _kEventSource 中，然后在表日歷中顯示它們，但是我的代碼不起作用，也沒有顯示任何錯誤或打印任何內容。 該文件為package默認自帶的utils文件。 我剛剛評論了循環生成事件的代碼，並想從數據庫中加載我自己的事件。 我如何 go 關於它以及為什么代碼沒有運行。 謝謝

import 'dart:collection';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:saajnairobi/announcementapi.dart';
import 'package:table_calendar/table_calendar.dart';
import 'advertannouncements.dart';
import 'package:http/http.dart' as http;

import 'announcementsapi.dart';


/// Example event class.
class Event {
  final String title;

  const Event(this.title);

  @override
  String toString() => title;
}

// LinkedHashMap<DateTime, List<AppEvent>>? _groupedEvents;
class AppEvent {
  late String id;
  late String userId;
  late String title;
  late String description;
  late DateTime startDate;
}

// this is the code that is not working , even the print is not working and it doesnt have an error ********************************************
 Map<DateTime, List<Event>> _kEventSource = {}; 

 Future<List<Welcome>> mike() async {
  String url =''; //my url goes here
  final response = await http.get(Uri.parse(url));
    print(response.body);
  if(response.statusCode == 200){
    print(response.body);
    var jsonData = welcomeFromMap(response.body).toList();
      jsonData.forEach((element) {
      _kEventSource[DateTime(  
        element.date.year,
        element.date.month,
        element.date.day,
      )] = _kEventSource[DateTime(
                element.date.year,
                element.date.month,
                element.date.day,
              )] !=
              null
          ? [
              ...?_kEventSource[DateTime(
                element.date.year,
                element.date.month,
                element.date.day,
              )],
              element.date
            ]
          : [element.date];
  });
    return welcomeFromMap(response.body).toList();
  } else {
    throw Exception('Failed to load data');
  }
}

/// Example events.
/// Using a [LinkedHashMap] is highly recommended if you decide to use a map.
final kEvents = LinkedHashMap<DateTime, List<Event>>(
  equals: isSameDay,
  hashCode: getHashCode,
  // actual code 
)..addAll(_kEventSource);

// the actual code that comes with the package 

// final _kEventSource = Map.fromIterable(List.generate(365, (index) => index),
//     key: (item) => DateTime.utc(kFirstDay.year, kFirstDay.month, item+1),
//     value: (item) => List.generate(
//         1, (index) => Event('Muharram')))
//   ..addAll({
//     kToday: [
//       Event('Event 1'),
//       Event('Muharram 4th'),
//     ],
//   });

int getHashCode(DateTime key) {
  return key.day * 1000000 + key.month * 10000 + key.year;
}

/// Returns a list of [DateTime] objects from [first] to [last], inclusive.
List<DateTime> daysInRange(DateTime first, DateTime last) {
  final dayCount = last.difference(first).inDays + 1;
  // print(dayCount);
  return List.generate(
    dayCount,
    (index) => DateTime.utc(first.year, first.month, first.day + index),
  );
}

final kToday = DateTime.now();
final kFirstDay = DateTime(2022);
final kLastDay = DateTime(2062);

Answer 1

您需要 substring 年月日，然后將最后一個 element.date 放入 Event() 並將其更改為 element.title ，就像我在下面所做的那樣。

Map<DateTime, List<Event>> _kEventSource = {};
     Future<List<Welcome>> mike() async {
      String url ='link';
      final response = await http.get(Uri.parse(url));
        // print(response.body);
      if(response.statusCode == 200){
        print("response is 200");
        List jsonData = welcomeFromMap(response.body).toList();
        print(jsonData);
        jsonData.forEach((element) {
          // print(element.date.substring(8,10));
        int year = int.parse(element.date.substring(0,4));
        int month = int.parse(element.date.substring(5,7));
        int day = int.parse(element.date.substring(8,10));
        _kEventSource[DateTime(
            year,
            month,
            day,
          )] = _kEventSource[DateTime(
                    year,
                    month,
                    day,
                  )] !=
                  null
              ? [
                  ...?_kEventSource[DateTime(
                    year,
                    month,
                    day,
                  )],
                  element.date
                ]
              : [Event(element.title)];
      });
    
      kEvents = LinkedHashMap<DateTime, List<Event>>(
        equals: isSameDay,
        hashCode: getHashCode,
      )..addAll(_kEventSource);
    
        return welcomeFromMap(response.body).toList();
      } else {
        print("response not 200");
        throw Exception('Failed to load data');
      }
    }