DateRagePicker颤振

Question

我正在showModalBottomSheet中使用date_range_picker: ^1.0.5 flutter软件包。但是他们的包装使用代码给了我一个例外。

代码

final List<DateTime> picked = await DateRagePicker.showDatePicker(
          context: context,
          initialFirstDate: new DateTime.now(),
          initialLastDate: (new DateTime.now()).add(new Duration(days: 7)),
          firstDate: new DateTime(2015),
          lastDate: new DateTime(2020)
      );
      if (picked != null && picked.length == 2) {
          print(picked);
      }

例外：

VERBOSE-2：ui_dart_state.cc（157）]未处理的异常：'package：date_range_picker / date_range_picker.dart'：失败的断言：1280行pos 10：'！initialLastDate.isAfter（lastDate）'：initialDate必须处于启用状态在lastDate之前

此代码或程序包异常是否存在问题？

Answer 1

您可以在下面复制粘贴运行完整代码
您可以使用lastDate: new DateTime(2021));
因为DateTime(2020)的意思是2020-01-01T00:00:00.000

工作演示

完整代码

import 'package:flutter/material.dart';
import 'package:date_range_picker/date_range_picker.dart' as DateRagePicker;

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
        visualDensity: VisualDensity.adaptivePlatformDensity,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() async {
    print(DateTime(2020).toIso8601String());

    final List<DateTime> picked = await DateRagePicker.showDatePicker(
        context: context,
        initialFirstDate: new DateTime.now(),
        initialLastDate: (new DateTime.now()).add(new Duration(days: 7)),
        firstDate: new DateTime(2015),
        lastDate: new DateTime(2021));
    if (picked != null && picked.length == 2) {
      print(picked);
    }

    setState(() {
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headline4,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ),
    );
  }
}