Convert flutter Datetime into Firebase Timestamp

[flutter testing]

Does anyone has any suggestion to convert flutter Datetime into Firebase Timestamp so it can be stored into firebase database as firebase does not have any Datetime field?

Timestamp _dueDate = onValue as Timestamp // this syntax to convert Datetime into Timestamp gives an error. Error is with or without cast.

Error with cast:

E/flutter ( 9348): [ERROR:flutter/lib/ui/ui_dart_state.cc(148)] Unhandled Exception: type 'DateTime' is not a subtype of type 'Timestamp' in type cast

Here's the code:
//.......................................................

Widget inputDueDate() {
  return Padding(padding: new EdgeInsets.only(left: 10.0, right: 10.0),
    child: TextField(
      onTap: ()=> ShowDateCalenddar(context, ).then((onValue){
        Timestamp _dueDate = onValue as Timestamp; // Convert DateTime into timestamp so it can be stored into firebase document
      }),

      style: Theme.of(context).textTheme.body2,
      controller: _dueDateController,
      decoration: InputDecoration(labelText: homeworkConfig.dueDateLabel,
        enabled: (widget.CRUDFlag == 'READ' ? false: true),
      ),
      maxLines: 1,
    ),
  );
}


Future<DateTime> ShowDateCalenddar(BuildContext context, ) async {
  final DateTime picked = await showDatePicker(
      context: context,
      initialDate: DateTime.now(),
      firstDate: DateTime(2019, 1),
      lastDate: DateTime(2101));
  if (picked != null) {
    setState(() {
      _dueDateController = TextEditingController(text: picked.toString());
    });
  }
  return picked;
}

[Jagannathan Srinivasan]

I store timestamp in firebase as milliseconds since epoch. It works very well for me

Get Outlook for Android

---

From: flutt...@googlegroups.com <flutt...@googlegroups.com> on behalf of flutter testing <fluttera...@gmail.com>
Sent: Saturday, September 14, 2019 12:29:43 PM
To: Flutter Development (flutter-dev) <flutt...@googlegroups.com>
Subject: Convert flutter Datetime into Firebase Timestamp

 

--
You received this message because you are subscribed to the Google Groups "Flutter Development (flutter-dev)" group.
To unsubscribe from this group and stop receiving emails from it, send an email to flutter-dev...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/flutter-dev/9413a322-7c64-437d-80c9-687f86fdcecd%40googlegroups.com.

[flutter testing]

Thanks. Can you pl share your code? Converting from Datetime to millisecondsSinceEpoch, and then converting it back to Datetime is changing the value of the data. 

onTap: () => ShowDateCalenddar(
  context,
).then((onValue) {
  printText('1. onValue', onValue.toString());
  var _dueDate = onValue.millisecondsSinceEpoch; // Convert DateTime into timestamp so it can be stored into firebase document
  printText('2. onValue.millisecondsSinceEpoch', _dueDate.toString());
  DateTime _dueDate2 = DateTime.fromMicrosecondsSinceEpoch(_dueDate);
  printText('3. DateTime.fromMicrosecondsSinceEpoch(_dueDate)', '$_dueDate2');

}),

I/flutter (12387): onValue : 2019-09-14 12:14:19.119163

I/flutter (12387): onValue.millisecondsSinceEpoch : 1568477659119

I/flutter (12387): DateTime.fromMicrosecondsSinceEpoch(_dueDate) : 1970-01-18 22:41:17.659119

To unsubscribe from this group and stop receiving emails from it, send an email to flutt...@googlegroups.com.

[Jagannathan Srinivasan]

You seem to have a small typo...you're using millisecondsSinceEpoch in one conversion and microssecondsSinceEpoch in the reverse :-)

To unsubscribe from this group and stop receiving emails from it, send an email to flutter-dev...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/flutter-dev/8d2de50b-d6f4-43da-9106-81f9ad21b79d%40googlegroups.com.

[Muhammad Kashif]

You can convert flutter DateTime into firebase Timestamp by using function Timestamp.fromMillisecondsSinceEpoch()

Timestamp.fromMillisecondsSinceEpoch(DateTime.now().millisecondsSinceEpoch).toString()