Question

我从这个软件包https://pub.dev/packages/stop_watch_timer中得到了这个计时器

并且我正在尝试将初始值传递给它：

DateTime dateNow = DateTime.now () // this is my current Time.

Duration initialTime;

initialTime = dateNow.difference (timeStampfromFirestore.toDate ());

initialTime ->这是我希望计时器启动的值，但是我无法理解程序包的工作原理

例如：

计时器现在开始像这样：00:00:00

例如，我正尝试使其开始：00:15:00

其中initialTime = 00:15:00

import 'package:flutter/material.dart';
import 'package:stop_watch_timer/stop_watch_timer.dart';

void main() => runApp(MyApp());

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  final StopWatchTimer _stopWatchTimer = StopWatchTimer(
    onChange: (value) => print('onChange $value'),
    onChangeSecond: (value) => print('onChangeSecond $value'),
    onChangeMinute: (value) => print('onChangeMinute $value'),
  );

  final _scrollController = ScrollController();

  @override
  void initState() {
    super.initState();
    _stopWatchTimer.rawTime.listen((value) =>
        print('rawTime $value ${StopWatchTimer.getDisplayTime(value)}'));
    _stopWatchTimer.minuteTime.listen((value) => print('minuteTime $value'));
    _stopWatchTimer.secondTime.listen((value) => print('secondTime $value'));
    _stopWatchTimer.records.listen((value) => print('records $value'));
    _stopWatchTimer.onExecute.add(StopWatchExecute.start);

    /// Can be set preset time. This case is "00:01.23".
    // _stopWatchTimer.setPresetTime(mSec: 1234);
  }

  @override
  void dispose() async {
    super.dispose();
    await _stopWatchTimer.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Plugin example app'),
        ),
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            crossAxisAlignment: CrossAxisAlignment.center,
            children: <Widget>[
              /// Display stop watch time
              Padding(
                padding: const EdgeInsets.only(bottom: 0),
                child: StreamBuilder<int>(
                  stream: _stopWatchTimer.rawTime,
                  initialData: _stopWatchTimer.rawTime.value,
                  builder: (context, snap) {
                    final value = snap.data;
                    final displayTime = StopWatchTimer.getDisplayTime(value);

                    return Column(
                      children: <Widget>[
                        Padding(
                          padding: const EdgeInsets.all(8),
                          child: Text(
                            displayTime,
                            style: TextStyle(
                                fontSize: 40,
                                fontFamily: 'Helvetica',
                                fontWeight: FontWeight.bold),
                          ),
                        ),
                        Padding(
                          padding: const EdgeInsets.all(8),
                          child: Text(
                            value.toString(),
                            style: TextStyle(
                                fontSize: 16,
                                fontFamily: 'Helvetica',
                                fontWeight: FontWeight.w400),
                          ),
                        ),
                      ],
                    );
                  },
                ),
              ),

              /// Display every minute.
              Padding(
                padding: const EdgeInsets.only(bottom: 0),
                child: StreamBuilder<int>(
                  stream: _stopWatchTimer.minuteTime,
                  initialData: _stopWatchTimer.minuteTime.value,
                  builder: (context, snap) {
                    final value = snap.data;
                    print('Listen every minute. $value');
                    return Column(
                      children: <Widget>[
                        Padding(
                            padding: const EdgeInsets.all(8),
                            child: Row(
                              mainAxisAlignment: MainAxisAlignment.center,
                              crossAxisAlignment: CrossAxisAlignment.center,
                              children: <Widget>[
                                const Padding(
                                  padding: EdgeInsets.symmetric(horizontal: 4),
                                  child: Text(
                                    'minute',
                                    style: TextStyle(
                                      fontSize: 17,
                                      fontFamily: 'Helvetica',
                                    ),
                                  ),
                                ),
                                Padding(
                                  padding:
                                      const EdgeInsets.symmetric(horizontal: 4),
                                  child: Text(
                                    value.toString(),
                                    style: TextStyle(
                                        fontSize: 30,
                                        fontFamily: 'Helvetica',
                                        fontWeight: FontWeight.bold),
                                  ),
                                ),
                              ],
                            )),
                      ],
                    );
                  },
                ),
              ),

              /// Display every second.
              Padding(
                padding: const EdgeInsets.only(bottom: 0),
                child: StreamBuilder<int>(
                  stream: _stopWatchTimer.secondTime,
                  initialData: _stopWatchTimer.secondTime.value,
                  builder: (context, snap) {
                    final value = snap.data;
                    print('Listen every second. $value');
                    return Column(
                      children: <Widget>[
                        Padding(
                            padding: const EdgeInsets.all(8),
                            child: Row(
                              mainAxisAlignment: MainAxisAlignment.center,
                              crossAxisAlignment: CrossAxisAlignment.center,
                              children: <Widget>[
                                const Padding(
                                  padding: EdgeInsets.symmetric(horizontal: 4),
                                  child: Text(
                                    'second',
                                    style: TextStyle(
                                      fontSize: 17,
                                      fontFamily: 'Helvetica',
                                    ),
                                  ),
                                ),
                                Padding(
                                  padding:
                                      const EdgeInsets.symmetric(horizontal: 4),
                                  child: Text(
                                    value.toString(),
                                    style: TextStyle(
                                        fontSize: 30,
                                        fontFamily: 'Helvetica',
                                        fontWeight: FontWeight.bold),
                                  ),
                                ),
                              ],
                            )),
                      ],
                    );
                  },
                ),
              ),

              /// Lap time.
              Container(
                height: 120,
                margin: const EdgeInsets.all(8),
                child: StreamBuilder<List<StopWatchRecord>>(
                  stream: _stopWatchTimer.records,
                  initialData: _stopWatchTimer.records.value,
                  builder: (context, snap) {
                    final value = snap.data;
                    if (value.isEmpty) {
                      return Container();
                    }
                    Future.delayed(const Duration(milliseconds: 100), () {
                      _scrollController.animateTo(
                          _scrollController.position.maxScrollExtent,
                          duration: const Duration(milliseconds: 200),
                          curve: Curves.easeOut);
                    });
                    print('Listen records. $value');
                    return ListView.builder(
                      controller: _scrollController,
                      scrollDirection: Axis.vertical,
                      itemBuilder: (BuildContext context, int index) {
                        final data = value[index];
                        return Column(
                          children: <Widget>[
                            Padding(
                              padding: const EdgeInsets.all(8),
                              child: Text(
                                '${index + 1} ${data.displayTime}',
                                style: TextStyle(
                                    fontSize: 17,
                                    fontFamily: 'Helvetica',
                                    fontWeight: FontWeight.bold),
                              ),
                            ),
                            const Divider(
                              height: 1,
                            )
                          ],
                        );
                      },
                      itemCount: value.length,
                    );
                  },
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}

Answer 1

可以使用setPresetTime接口。

请参阅。 https://github.com/hukusuke1007/stop_watch_timer

Set Preset Time
Can be set preset time. This case is "00:01.23". When timer is idle state, can be set this.

// Set Millisecond.
_stopWatchTimer.setPresetTime(mSec: 1234);

// Set Hours. (ex. 1 hours)
_stopWatchTimer.setPresetHoursTime(1);

// Set Minute. (ex. 30 minute)
_stopWatchTimer.setPresetMinuteTime(30);

// Set Second. (ex. 120 second)
_stopWatchTimer.setPresetSecondTime(120);

如何将初始值传递给Timer小部件-Flutter

1 个答案: