FlutterUnit/lib/views/pages/register/send_code.dart

import 'dart:async';

import 'package:flutter/material.dart';

/// create by 张风捷特烈 on 2021/1/17
/// contact me by email 1981462002@qq.com
/// 说明:

class CountDownWidget extends StatefulWidget {
  final VoidCallback onPress;

  CountDownWidget({Key key, this.onPress}) : super(key: key);

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

class _CountDownWidgetState extends State<CountDownWidget> {
  Timer timer;
  int count = 60;
  bool startTimer = false;

  @override
  void initState() {
    super.initState();

  }

  @override
  Widget build(BuildContext context) {
    return TextButton(
        onPressed: startTimer?null:() {
          timer = Timer.periodic(Duration(seconds: 1), _update);
          setState(() {
            startTimer = true;
          });
        },
        child: Text(startTimer?'$count 秒后重试':'获取验证码'));
  }

  void _update(Timer timer) {
    count--;
    if (count == 0) {
      timer.cancel();
      startTimer = false;
      count=5;
    }
    setState(() {});
  }
}