As stated, I am trying to use the flutter table_calendar: 2.3.0 and I'm not sure how to add the json data to the Map<DateTime,List> to display dates.

I'm using the start date as the datetime and the event "list" as the data that I'm utilizing.

Here is my json data:

 "Events": [
        {
            "id": 1,
            "event_name": "Cake tasting",
            "event_photo": "https://dispensaries.s3.amazonaws.com/event_photo/Southern_Cali_Kush_3.jpg",
            "vendor_name": {
                "id": 1,
                "vendor": "Tastey Cakes"
            },
            "refund_available": false,
            "website": "www.foodcakes.com",
            "share_count": 0,
            "check_in_count": 0,
            "street_address": "123 Fake Street",
            "city": "Brooklynn",
            "state": "NY",
            "zipcode": "12312",
            "event_tagline": "Taste my cakes",
            "details": "Cake tasting",
            "start_date": "2020-11-03",
            "start_time": "23:33:00",
            "end_time": "23:33:00",
            "attendees": []
        }
    ]

Here is the map I'm using to add the data to the _event variable that holds the new date data:

 Map<DateTime, List> _events = {};

void _getEventDates(data) { Map<String, dynamic> newMap = {};

for (int i = 0; i < data.length; i++) {
  newMap = {
    data.startingTime, [data.name]
  } as Map<String, dynamic>;
  };
}

Could someone assist getting the json data into the format needed to display on the calendar?


Solution 1: Ali Qanbari

This convertJsonToDateMap function will do this for you:

Map<DateTime, List> convertJsonToDateMap(String jsonSource) {
  var json = jsonDecode(jsonSource);
  var jsonEvents = json['Events'];
  Map<DateTime, List<String>> events = {};
  for(var event in jsonEvents){
    var date = parseDate(event['start_date']);
    events.putIfAbsent(date, () => <String>[]);
    events[date].add(event['event_name']);
  }
  return events;
}

DateTime parseDate(String date) {
  var parts = date.split('-').map(int.tryParse).toList();
  return DateTime(parts[0], parts[1], parts[2]);
}

Github gist: https://gist.github.com/ali2236/3cddbbdafbc1632ddd7cfc23a1758af5