如何在 Flutter 中实现 SingleLine 水平 CalendarView

Question

我是 Flutter 的新手。如何在颤动中实现SingleLine水平滚动CalendarView和日期选择。 请找到预期CalendarView 的下图。帮助将不胜感激

Expected CalendarView

Answer 1

你可以使用包https://pub.dev/packages/table_calendar
在月份模式下，只会显示一行日期

代码sn-p

return TableCalendar(
      locale: 'pl_PL',
      calendarController: _calendarController,
      events: _events,
      holidays: _holidays,
      initialCalendarFormat: CalendarFormat.month,
      formatAnimation: FormatAnimation.slide,
      startingDayOfWeek: StartingDayOfWeek.sunday,
      availableGestures: AvailableGestures.all,
      availableCalendarFormats: const {
        CalendarFormat.month: '',
        CalendarFormat.week: '',
      },

示例代码中，_buildButtons() 和 _buildEventList() 如果不需要，可以备注

body: Column(
        mainAxisSize: MainAxisSize.max,
        children: <Widget>[
          // Switch out 2 lines below to play with TableCalendar's settings
          //-----------------------
          _buildTableCalendar(),
          // _buildTableCalendarWithBuilders(),
          //const SizedBox(height: 8.0),
          //_buildButtons(),
          //const SizedBox(height: 8.0),
          //Expanded(child: _buildEventList()),
        ],
      ),

完整示例代码

//  Copyright (c) 2019 Aleksander Woźniak
//  Licensed under Apache License v2.0

import 'package:flutter/material.dart';
import 'package:intl/date_symbol_data_local.dart';
import 'package:table_calendar/table_calendar.dart';

// Example holidays
final Map<DateTime, List> _holidays = {
  DateTime(2019, 1, 1): ['New Year\'s Day'],
  DateTime(2019, 1, 6): ['Epiphany'],
  DateTime(2019, 2, 14): ['Valentine\'s Day'],
  DateTime(2019, 4, 21): ['Easter Sunday'],
  DateTime(2019, 4, 22): ['Easter Monday'],
};

void main() {
  initializeDateFormatting().then((_) => runApp(MyApp()));
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Table Calendar Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Table Calendar Demo'),
    );
  }
}

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

  final String title;

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

class _MyHomePageState extends State<MyHomePage> with TickerProviderStateMixin {
  Map<DateTime, List> _events;
  List _selectedEvents;
  AnimationController _animationController;
  CalendarController _calendarController;

  @override
  void initState() {
    super.initState();
    final _selectedDay = DateTime.now();

    _events = {
      _selectedDay.subtract(Duration(days: 30)): ['Event A0', 'Event B0', 'Event C0'],
      _selectedDay.subtract(Duration(days: 27)): ['Event A1'],
      _selectedDay.subtract(Duration(days: 20)): ['Event A2', 'Event B2', 'Event C2', 'Event D2'],
      _selectedDay.subtract(Duration(days: 16)): ['Event A3', 'Event B3'],
      _selectedDay.subtract(Duration(days: 10)): ['Event A4', 'Event B4', 'Event C4'],
      _selectedDay.subtract(Duration(days: 4)): ['Event A5', 'Event B5', 'Event C5'],
      _selectedDay.subtract(Duration(days: 2)): ['Event A6', 'Event B6'],
      _selectedDay: ['Event A7', 'Event B7', 'Event C7', 'Event D7'],
      _selectedDay.add(Duration(days: 1)): ['Event A8', 'Event B8', 'Event C8', 'Event D8'],
      _selectedDay.add(Duration(days: 3)): Set.from(['Event A9', 'Event A9', 'Event B9']).toList(),
      _selectedDay.add(Duration(days: 7)): ['Event A10', 'Event B10', 'Event C10'],
      _selectedDay.add(Duration(days: 11)): ['Event A11', 'Event B11'],
      _selectedDay.add(Duration(days: 17)): ['Event A12', 'Event B12', 'Event C12', 'Event D12'],
      _selectedDay.add(Duration(days: 22)): ['Event A13', 'Event B13'],
      _selectedDay.add(Duration(days: 26)): ['Event A14', 'Event B14', 'Event C14'],
    };

    _selectedEvents = _events[_selectedDay] ?? [];

    _calendarController = CalendarController();

    _animationController = AnimationController(
      vsync: this,
      duration: const Duration(milliseconds: 400),
    );

    _animationController.forward();
  }

  @override
  void dispose() {
    _animationController.dispose();
    _calendarController.dispose();
    super.dispose();
  }

  void _onDaySelected(DateTime day, List events) {
    print('CALLBACK: _onDaySelected');
    setState(() {
      _selectedEvents = events;
    });
  }

  void _onVisibleDaysChanged(DateTime first, DateTime last, CalendarFormat format) {
    print('CALLBACK: _onVisibleDaysChanged');
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Column(
        mainAxisSize: MainAxisSize.max,
        children: <Widget>[
          // Switch out 2 lines below to play with TableCalendar's settings
          //-----------------------
          _buildTableCalendar(),
          // _buildTableCalendarWithBuilders(),
          const SizedBox(height: 8.0),
          _buildButtons(),
          const SizedBox(height: 8.0),
          Expanded(child: _buildEventList()),
        ],
      ),
    );
  }

  // Simple TableCalendar configuration (using Styles)
  Widget _buildTableCalendar() {
    return TableCalendar(
      calendarController: _calendarController,
      events: _events,
      holidays: _holidays,
      startingDayOfWeek: StartingDayOfWeek.monday,
      calendarStyle: CalendarStyle(
        selectedColor: Colors.deepOrange[400],
        todayColor: Colors.deepOrange[200],
        markersColor: Colors.brown[700],
        outsideDaysVisible: false,
      ),
      headerStyle: HeaderStyle(
        formatButtonTextStyle: TextStyle().copyWith(color: Colors.white, fontSize: 15.0),
        formatButtonDecoration: BoxDecoration(
          color: Colors.deepOrange[400],
          borderRadius: BorderRadius.circular(16.0),
        ),
      ),
      onDaySelected: _onDaySelected,
      onVisibleDaysChanged: _onVisibleDaysChanged,
    );
  }

  // More advanced TableCalendar configuration (using Builders & Styles)
  Widget _buildTableCalendarWithBuilders() {
    return TableCalendar(
      locale: 'pl_PL',
      calendarController: _calendarController,
      events: _events,
      holidays: _holidays,
      initialCalendarFormat: CalendarFormat.month,
      formatAnimation: FormatAnimation.slide,
      startingDayOfWeek: StartingDayOfWeek.sunday,
      availableGestures: AvailableGestures.all,
      availableCalendarFormats: const {
        CalendarFormat.month: '',
        CalendarFormat.week: '',
      },
      calendarStyle: CalendarStyle(
        outsideDaysVisible: false,
        weekendStyle: TextStyle().copyWith(color: Colors.blue[800]),
        holidayStyle: TextStyle().copyWith(color: Colors.blue[800]),
      ),
      daysOfWeekStyle: DaysOfWeekStyle(
        weekendStyle: TextStyle().copyWith(color: Colors.blue[600]),
      ),
      headerStyle: HeaderStyle(
        centerHeaderTitle: true,
        formatButtonVisible: false,
      ),
      builders: CalendarBuilders(
        selectedDayBuilder: (context, date, _) {
          return FadeTransition(
            opacity: Tween(begin: 0.0, end: 1.0).animate(_animationController),
            child: Container(
              margin: const EdgeInsets.all(4.0),
              padding: const EdgeInsets.only(top: 5.0, left: 6.0),
              color: Colors.deepOrange[300],
              width: 100,
              height: 100,
              child: Text(
                '${date.day}',
                style: TextStyle().copyWith(fontSize: 16.0),
              ),
            ),
          );
        },
        todayDayBuilder: (context, date, _) {
          return Container(
            margin: const EdgeInsets.all(4.0),
            padding: const EdgeInsets.only(top: 5.0, left: 6.0),
            color: Colors.amber[400],
            width: 100,
            height: 100,
            child: Text(
              '${date.day}',
              style: TextStyle().copyWith(fontSize: 16.0),
            ),
          );
        },
        markersBuilder: (context, date, events, holidays) {
          final children = <Widget>[];

          if (events.isNotEmpty) {
            children.add(
              Positioned(
                right: 1,
                bottom: 1,
                child: _buildEventsMarker(date, events),
              ),
            );
          }

          if (holidays.isNotEmpty) {
            children.add(
              Positioned(
                right: -2,
                top: -2,
                child: _buildHolidaysMarker(),
              ),
            );
          }

          return children;
        },
      ),
      onDaySelected: (date, events) {
        _onDaySelected(date, events);
        _animationController.forward(from: 0.0);
      },
      onVisibleDaysChanged: _onVisibleDaysChanged,
    );
  }

  Widget _buildEventsMarker(DateTime date, List events) {
    return AnimatedContainer(
      duration: const Duration(milliseconds: 300),
      decoration: BoxDecoration(
        shape: BoxShape.rectangle,
        color: _calendarController.isSelected(date)
            ? Colors.brown[500]
            : _calendarController.isToday(date) ? Colors.brown[300] : Colors.blue[400],
      ),
      width: 16.0,
      height: 16.0,
      child: Center(
        child: Text(
          '${events.length}',
          style: TextStyle().copyWith(
            color: Colors.white,
            fontSize: 12.0,
          ),
        ),
      ),
    );
  }

  Widget _buildHolidaysMarker() {
    return Icon(
      Icons.add_box,
      size: 20.0,
      color: Colors.blueGrey[800],
    );
  }

  Widget _buildButtons() {
    return Column(
      children: <Widget>[
        Row(
          mainAxisSize: MainAxisSize.max,
          mainAxisAlignment: MainAxisAlignment.spaceEvenly,
          children: <Widget>[
            RaisedButton(
              child: Text('month'),
              onPressed: () {
                setState(() {
                  _calendarController.setCalendarFormat(CalendarFormat.month);
                });
              },
            ),
            RaisedButton(
              child: Text('2 weeks'),
              onPressed: () {
                setState(() {
                  _calendarController.setCalendarFormat(CalendarFormat.twoWeeks);
                });
              },
            ),
            RaisedButton(
              child: Text('week'),
              onPressed: () {
                setState(() {
                  _calendarController.setCalendarFormat(CalendarFormat.week);
                });
              },
            ),
          ],
        ),
        const SizedBox(height: 8.0),
        RaisedButton(
          child: Text('setDay 10-07-2019'),
          onPressed: () {
            _calendarController.setSelectedDay(DateTime(2019, 7, 10), runCallback: true);
          },
        ),
      ],
    );
  }

  Widget _buildEventList() {
    return ListView(
      children: _selectedEvents
          .map((event) => Container(
                decoration: BoxDecoration(
                  border: Border.all(width: 0.8),
                  borderRadius: BorderRadius.circular(12.0),
                ),
                margin: const EdgeInsets.symmetric(horizontal: 8.0, vertical: 4.0),
                child: ListTile(
                  title: Text(event.toString()),
                  onTap: () => print('$event tapped!'),
                ),
              ))
          .toList(),
    );
  }
}