如何使用 WebRTC 在 React JSX 中启动和停止网络摄像头 stream 和麦克风？

Question

I already have getUserMedia working in my ReactJSX file. I'm new to ReactJSX, and i've viewed some stackoverflow posts related to this, but unfortunately many of the existing instructions include a line of code/function that is deprecated by webRTC.

However, I haven't been able to figure how to stop the web cam stream and microphone in React JSX , in particular. And since this language is quite new for me, can anyone help me?

This is the working code I have before the return() tag in React JSX

  navigator.mediaDevices.getUserMedia({
      audio: true,
      video: true
    })
    .then(stream => {
      document.getElementById("startstream").srcObject = stream;
    })

And this is the working code I have to display and enable the camera and microphone after the return() tag in React JSX:

<video id="startstream" autoPlay />

Both of those code snippets work, and it allows the user to start the stream/start their microphone, but how do I start and stop the webcam/microphone using a button in ReactJSX? I've seen something similar online using another coding language, but if anyone code help me to get it to work with ReactJSX, that would be appreciated.

Answer 1

import React from "react";
import "./styles.css";

class WebRTCSample extends React.Component {
  constructor(props) {
    super(props);
    this.state = { localStream: null };
  }

  componentDidMount() {}

  startWebCam = () => {
    const that = this;
    navigator.mediaDevices
      .getUserMedia({
        audio: true,
        video: true
      })
      .then((stream) => {
        that.setState({ localStream: stream });
      });
  };

  stopWebCam = () => {
    this.state.localStream.getTracks().forEach((track) => {
      track.stop();
    });
  };

  render() {
    return (
      <div className="App">
        {/* <h1>Hello GetUserMedia</h1> */}
        {this.state.localStream && (
          <video
            autoPlay
            ref={(video) => {
              if (video) {
                video.srcObject = this.state.localStream;
              }
            }}
            // src={this.state.localStream}
          />
        )}
        <div className="startStopWebCam">
          <button
            className="WebCamButton"
            onClick={this.startWebCam.bind(this)}
          >
            Start
          </button>
          <button className="WebCamButton" onClick={this.stopWebCam.bind(this)}>
            Stop
          </button>
        </div>
      </div>
    );
  }
}

export default WebRTCSample;

DEMO