react voice recognition

1import React, { useState, useEffect } from 'react';
2// the button form material-ui is optional
3// npm install @material-ui/core
4import Button from '@material-ui/core/Button';
5
6const SpeechRecognition =
7  window.SpeechRecognition || window.webkitSpeechRecognition
8const mic = new SpeechRecognition()
9
10mic.continuous = true
11mic.interimResults = true
12mic.lang = 'en-US'
13
14const RecordButton = () => {
15
16    const [isMicOn, setIsMicOn] = useState(false);
17
18    var buttonColour;
19    var buttonLabel;
20
21    if (isMicOn) {
22        buttonColour = "secondary";
23        buttonLabel = "Recording...";
24    } else {
25        buttonColour = "primary";
26        buttonLabel = "Record";
27    }
28
29    useEffect(() => {
30        handleListen()
31      }, [isMicOn])
32    
33    const handleListen = () => {
34    if (isMicOn) {
35        mic.start()
36        mic.onend = () => {
37        console.log('continue..')
38        mic.start()
39        }
40    } else {
41        mic.stop()
42        mic.onend = () => {
43        console.log('Stopped Mic on Click')
44        }
45    }
46    mic.onstart = () => {
47        console.log('Mics on')
48    }
49    
50    mic.onresult = event => {
51        const transcript = Array.from(event.results)
52        .map(result => result[0])
53        .map(result => result.transcript)
54        .join('')
55        console.log(transcript)
56        mic.onerror = event => {
57        console.log(event.error)
58          }
59        }
60      }
61	// if you don't want to us the button from Material-ui, just change Button to button
62    return(
63        <Button variant="contained" color={buttonColour} onClick={() => {setIsMicOn(!isMicOn)}} >{buttonLabel}</Button>
64    )
65}
66
67export default RecordButton;