flutter_kit_mic 0.0.1

flutter_kit_mic: ^0.0.1 copied to clipboard

example/lib/main.dart

import 'dart:async';
import 'dart:math';

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_kit_mic/flutter_kit_mic.dart';

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

class MyApp extends StatefulWidget {
  const MyApp({super.key});

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  String _platformVersion = 'Unknown';
  final _flutterKitMicPlugin = FlutterKitMic();

  @override
  void initState() {
    super.initState();
    initPlatformState();
    _sub = FlutterKitMic.pcmStream();
    _sub!.listen((bytes) {
      // bytes: Int16 小端，单声道
      final rms = _rmsPcm16Le(bytes);
      final ref = 20e-6; // 参考声压（仅示例）
      setState(() {
        print('=================>. ${rms}');
        db = 20 * log(max(rms, 1.0) / ref);
      });
      // TODO: 用 db 驱动你的 LED
    });
  }

  // Platform messages are asynchronous, so we initialize in an async method.
  Future<void> initPlatformState() async {
    String platformVersion;
    // Platform messages may fail, so we use a try/catch PlatformException.
    // We also handle the message potentially returning null.
    try {
      platformVersion = await FlutterKitMic.getPlatformVersion() ?? 'Unknown platform version';
    } on PlatformException {
      platformVersion = 'Failed to get platform version.';
    }

    // If the widget was removed from the tree while the asynchronous platform
    // message was in flight, we want to discard the reply rather than calling
    // setState to update our non-existent appearance.
    if (!mounted) return;

    setState(() {
      _platformVersion = platformVersion;
    });
  }

  Stream<Uint8List>? _sub;
  double db = 0;
  Future<void> startMic() async {
    final ok = await FlutterKitMic.requestPermission();
    if (!ok) {
      // 引导用户去设置里开启
      return;
    }

    await FlutterKitMic.startRecorder(
      androidRunInForeground: true,
      androidNotificationTitle: 'Mic running',
      androidNotificationText: 'Listening in background',
    );
  }

  double _rmsPcm16Le(Uint8List bytes) {
    final len = bytes.lengthInBytes ~/ 2;
    double sum = 0;
    for (int i = 0; i < len; i++) {
      final lo = bytes[i * 2];
      final hi = bytes[i * 2 + 1];
      int s = (hi << 8) | lo;
      if (s > 32767) s -= 65536;
      sum += (s * s).toDouble();
    }
    return sqrt(sum / max(1, len)) / 32768.0; // 归一化
  }

  Future<void> stopMic() async {
    setState(() {
      db = 0;
    });
    await FlutterKitMic.stopRecorder();
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(title: const Text('Plugin example app')),
        body: Column(
          children: [
            Center(child: Text('Running on: $_platformVersion\n')),
            Text('db mic: $db\n'),
            SizedBox(
              width: 80,
              height: 40,
              child: InkWell(
                child: Text('recorder'),
                onTap: () {
                  startMic();
                },
              ),
            ),
            SizedBox(
              width: 80,
              height: 40,
              child: InkWell(
                child: Text('stop'),
                onTap: () {
                  stopMic();
                },
              ),
            ),
          ],
        ),
      ),
    );
  }
}