DEMO

const textarea = document.querySelector("#textarea") const btnGravar = document.querySelector("#btnGravar") const btnParar = document.querySelector("#btnParar") //const btnBaixar = document.querySelector("#btnBaixar") const btnLimpar = document.querySelector("#btnLimpar") class speechApi { constructor() { const SpeechToText = window.SpeechRecognition || window.webkitSpeechRecognition this.speechApi = new SpeechToText() this.output = textarea.output this.speechApi.continuous = true this.speechApi.lang = "pt-BR" this.speechApi.onresult = (e) => { var resultIndex = e.resultIndex var transcript = e.results[resultIndex][0].transcript textarea.value += transcript } } start() { this.speechApi.start() } stop() { this.speechApi.stop() } } var speech = new speechApi() btnGravar.addEventListener("click", () => { btnGravar.disabled = true btnParar.disabled = false speech.start() }) btnParar.addEventListener("click", () => { btnGravar.disabled = false btnParar.disabled = true speech.stop() }) /* btnBaixar.addEventListener('click', () => { var text = textarea.value var filename = "speech.txt" download(text, filename) }) function download(text, filename) { var element = document.createElement('a') element.setAttribute('href', 'data:text/plaincharset=utf-8,' + encodeURIComponent(text)) element.setAttribute('download', filename) element.style.display = 'none' document.body.appendChild(element) element.click() document.body.removeChild(element) }*/ btnLimpar.addEventListener("click", () => { textarea.value = "" btnGravar.disabled = false btnParar.disabled = true speech.stop() }) <!---->