flutter 倒数计时器（自定义时间）

Question

我使用了倒数计时器的基本代码，我想知道如何让用户自定义他们想要的时间量，而不是使用默认值（在我的例子中是 30 分钟或 1800 秒）。我只是想让他们选择他们想要的任何时间，例如 5 分钟、30 分钟、1 小时等。单击该按钮后可能是另一个按钮，或者可能会弹出一个窗口让他们选择时间？老实说，在这一点上有什么帮助，谢谢！

class timer extends StatefulWidget {
  const timer({Key? key}) : super(key: key);

  @override
  State<timer> createState() => _timerState();
}

class _timerState extends State<timer> {
   final int _duration = 1800;
  final CountDownController _controller = CountDownController();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
          child: CircularCountDownTimer(
        // Countdown duration in Seconds.
        duration: _duration,

        // Countdown initial elapsed Duration in Seconds.
        initialDuration: 0,

        // Controls (i.e Start, Pause, Resume, Restart) the Countdown Timer.
        controller: _controller,

        // Width of the Countdown Widget.
        width: MediaQuery.of(context).size.width / 2,

        // Height of the Countdown Widget.
        height: MediaQuery.of(context).size.height / 2,

        // Ring Color for Countdown Widget.
        ringColor: Colors.grey[300]!,

        // Ring Gradient for Countdown Widget.
        ringGradient: null,

        // Filling Color for Countdown Widget.
        fillColor: Color(0XFFffadad),

        // Filling Gradient for Countdown Widget.
        fillGradient: null,

        // Background Color for Countdown Widget.
        backgroundColor: Color(0XFFFDE2E4),

        // Background Gradient for Countdown Widget.
        backgroundGradient: null,

        // Border Thickness of the Countdown Ring.
        strokeWidth: 20.0,

        // Begin and end contours with a flat edge and no extension.
        strokeCap: StrokeCap.round,

        // Text Style for Countdown Text.
        textStyle: const TextStyle(
          fontSize: 33.0,
          color: Colors.white,
          fontWeight: FontWeight.bold,
        ),

        // Format for the Countdown Text.
        textFormat: CountdownTextFormat.S,

        // Handles Countdown Timer (true for Reverse Countdown (max to 0), false for Forward Countdown (0 to max)).
        isReverse: false,

        // Handles Animation Direction (true for Reverse Animation, false for Forward Animation).
        isReverseAnimation: false,

        // Handles visibility of the Countdown Text.
        isTimerTextShown: true,

        // Handles the timer start.
        autoStart: false,

        // This Callback will execute when the Countdown Starts.
        onStart: () {
          // Here, do whatever you want
          debugPrint('Countdown Started');
        },

        // This Callback will execute when the Countdown Ends.
        onComplete: () {
          // Here, do whatever you want
          debugPrint('Countdown Ended');
        },
      )),
      floatingActionButton: Row(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          const SizedBox(
            width: 30,
          ),
          _button(title: "Start", onPressed: () => _controller.start()),
          const SizedBox(
            width: 10,
            height: 200
          ),
          _button(title: "Pause", onPressed: () => _controller.pause()),
          const SizedBox(
            width: 10,
            height: 200
          ),
          _button(title: "Resume", onPressed: () => _controller.resume()),
          const SizedBox(
            width: 10,
            height: 200
          ),
          _button(title: "Restart",onPressed: () => _controller.restart(duration: _duration)),
          const SizedBox(
            width: 10,
            height: 200
          ),
        ],
      ),
    );
  }

  Widget _button({required String title, VoidCallback? onPressed}) {
    return Expanded(
        child: ElevatedButton(
      child: Text(
        title,
        style: const TextStyle(color: Colors.white),
      ),
      style: ButtonStyle(
        backgroundColor: MaterialStateProperty.all(Color(0XFFBCD4E6)),
      ),
      onPressed: onPressed,
    ));
  }
}

Answer 1

据我了解，您需要根据用户输入启动计时器这可以通过让用户选择您制作的 drop down 或 textfield 的计时器来完成，然后使用 Timer class

处理结果

Timer? myTimer ; 
int? userInput;
myTimerFunction(){
myTimer = Timer.periodic(const Duration(seconds: 1//or on your need), (_) =>startTimer());
}

startTimer(){
userInput++; // here will keep increase one value per 1/sec 

if(userInput == put here your value that should stop timer when it arrive it){
myTimer!.cancel(); // 
}

}

Answer 2

基本上你想要用于'Start / Restart'的是

_controller.restart(duration: (_duration).round()),

检查这个例子：

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

class TimerWidget extends StatefulWidget {
  const TimerWidget({Key? key}) : super(key: key);

  @override
  State<TimerWidget> createState() => _TimerWidgetState();
}

class _TimerWidgetState extends State<TimerWidget> {
  double _duration = 10;
  final CountDownController _controller = CountDownController();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: ListView(
        children: [
          Slider(
            min: 1,
            max: 20,
            divisions: 9,
            label: _duration.round().toString(),
            value: _duration,
            onChanged: (value) {
              setState(() {
                _duration = value;
              });
            },
          ),
          getCircularCountDownTimer(),
          Row(
            children: [
              _button(
                title: "Start",
                onPressed: () =>
                    _controller.restart(duration: (_duration).round()),
              ),
              const SizedBox(width: 10, height: 200),
              _button(
                title: "Pause",
                onPressed: () => _controller.pause(),
              ),
              const SizedBox(width: 10, height: 200),
              _button(
                title: "Resume",
                onPressed: () => _controller.resume(),
              ),
              const SizedBox(width: 10, height: 200),
              _button(
                title: "Restart",
                onPressed: () =>
                    _controller.restart(duration: (_duration).round()),
              ),
            ],
          ),
        ],
      ),
    );
  }

  Widget _button({required String title, VoidCallback? onPressed}) {
    return Expanded(
      child: ElevatedButton(
        style: ButtonStyle(
          backgroundColor: MaterialStateProperty.all(const Color(0XFFBCD4E6)),
        ),
        onPressed: onPressed,
        child: Text(
          title,
          style: const TextStyle(color: Colors.white),
        ),
      ),
    );
  }

  CircularCountDownTimer getCircularCountDownTimer() {
    return CircularCountDownTimer(
      duration: (_duration).round(),
      initialDuration: 0,
      controller: _controller,
      width: MediaQuery.of(context).size.width / 2,
      height: MediaQuery.of(context).size.height / 2,
      ringColor: Colors.grey[300]!,
      ringGradient: null,
      fillColor: Color(0XFFffadad),
      fillGradient: null,
      backgroundColor: Color(0XFFFDE2E4),
      backgroundGradient: null,
      strokeWidth: 20.0,
      strokeCap: StrokeCap.round,
      textStyle: const TextStyle(
        fontSize: 33.0,
        color: Colors.white,
        fontWeight: FontWeight.bold,
      ),
      textFormat: CountdownTextFormat.S,
      isReverse: false,
      isReverseAnimation: false,
      isTimerTextShown: true,
      autoStart: false,
      onStart: () {
        debugPrint('Countdown Started');
      },
      onComplete: () {
        debugPrint('Countdown Ended');
      },
    );
  }
}

您还可以将 _duration 作为计时器小部件的参数传递

flutter 倒数计时器（自定义时间）

flutter countdown timer (custom time)

dart

flutter

flutter-animation