Search code examples
javascripthtmlcssgoogle-sites

HTML, CSS, & JavaScript on Classic Google Sites - Why Video Recording Not Working?


There is this code here that I am wanting to upload to Classic Google Sites. (The code is at the very bottom of the link that you can click on.)

I can get the HTML and CSS parts up and running to do the video recorder but the JavaScript part I have no idea why it is not working. The code goes in that order.

I can get some JavaScript to do other stuff but not this. I type in < script > "Copied and Pasted JavaScript Code" < /script> when using the code from the site linked above but no success.

What am I doing wrong? How do I get this JavaScript part up and running?

<!-- HTML -->
<html lang="en-US">
<div class="left">
  <div id="startButton" class="button">
    Start
  </div>
  <h2>Preview</h2>
  <video id="preview" width="160" height="120" autoplay muted></video>
</div>
<div class="right">
  <div id="stopButton" class="button">
    Stop
  </div>
  <h2>Recording</h2>
  <video id="recording" width="160" height="120" controls></video>
  <a id="downloadButton" class="button">
    Download
  </a>
</div>
<div class="bottom">
  <pre id="log"></pre>
</div>
</html>
<!-- CSS -->
<script> //css
body {
  font: 14px "Open Sans", "Arial", sans-serif;
}

video {
  margin-top: 2px;
  border: 1px solid black;
}

.button {
  cursor: pointer;
  display: block;
  width: 160px;
  border: 1px solid black;
  font-size: 16px;
  text-align: center;
  padding-top: 2px;
  padding-bottom: 4px;
  color: white;
  background-color: darkgreen;
  text-decoration: none;
}

h2 {
  margin-bottom: 4px;
}

.left {
  margin-right: 10px;
  float: left;
  width: 160px;
  padding: 0px;
}

.right {
  margin-left: 10px;
  float: left;
  width: 160px;
  padding: 0px;
}

.bottom {
  clear: both;
  padding-top: 10px;
}
</script>
<!-- JavaScript (Doesn't Work) -->
<script>
let preview = document.getElementById("preview");
let recording = document.getElementById("recording");
let startButton = document.getElementById("startButton");
let stopButton = document.getElementById("stopButton");
let downloadButton = document.getElementById("downloadButton");
let logElement = document.getElementById("log");

let recordingTimeMS = 5000;
function log(msg) {
  logElement.innerHTML += msg + "\n";
}
function wait(delayInMS) {
  return new Promise(resolve => setTimeout(resolve, delayInMS));
}
function startRecording(stream, lengthInMS) {
  let recorder = new MediaRecorder(stream);
  let data = [];
 
  recorder.ondataavailable = event => data.push(event.data);
  recorder.start();
  log(recorder.state + " for " + (lengthInMS/1000) + " seconds...");
 
  let stopped = new Promise((resolve, reject) => {
    recorder.onstop = resolve;
    recorder.onerror = event => reject(event.name);
  });

  let recorded = wait(lengthInMS).then(
    () => recorder.state == "recording" && recorder.stop()
  );
 
  return Promise.all([
    stopped,
    recorded
  ])
  .then(() => data);
}
function stop(stream) {
  stream.getTracks().forEach(track => track.stop());
}
startButton.addEventListener("click", function() {
  navigator.mediaDevices.getUserMedia({
    video: true,
    audio: true
  }).then(stream => {
    preview.srcObject = stream;
    downloadButton.href = stream;
    preview.captureStream = preview.captureStream || preview.mozCaptureStream;
    return new Promise(resolve => preview.onplaying = resolve);
  }).then(() => startRecording(preview.captureStream(), recordingTimeMS))
  .then (recordedChunks => {
    let recordedBlob = new Blob(recordedChunks, { type: "video/webm" });
    recording.src = URL.createObjectURL(recordedBlob);
    downloadButton.href = recording.src;
    downloadButton.download = "RecordedVideo.webm";
    
    log("Successfully recorded " + recordedBlob.size + " bytes of " +
        recordedBlob.type + " media.");
  })
  .catch(log);
}, false);stopButton.addEventListener("click", function() {
  stop(preview.srcObject);
}, false);
</script>


Solution

  • Alright so from what I can see, the code is actually right and without any issue, if you are putting it all in a single HTML file, you might want to add a head tag and then put the CSS styling in there inside a tag instead of a tag.

    And Add the JS script inside the body tag at the end of the code, and it should run the code.

    I have added the code that works below so you can compare it to your code and see where the difference is :)

        <html lang="en-US">
      <head>
        <style>
          body {
          font: 14px "Open Sans", "Arial", sans-serif;
          }
        
          video {
          margin-top: 2px;
          border: 1px solid black;
          }
        
          .button {
          cursor: pointer;
          display: block;
          width: 160px;
          border: 1px solid black;
          font-size: 16px;
          text-align: center;
          padding-top: 2px;
          padding-bottom: 4px;
          color: white;
          background-color: darkgreen;
          text-decoration: none;
          }
        
          h2 {
          margin-bottom: 4px;
          }
        
          .left {
          margin-right: 10px;
          float: left;
          width: 160px;
          padding: 0px;
          }
        
          .right {
          margin-left: 10px;
          float: left;
          width: 160px;
          padding: 0px;
          }
        
          .bottom {
          clear: both;
          padding-top: 10px;
          }
        </style>
      </head>
      <body>
        <div class="left">
        <div id="startButton" class="button">
          Start
        </div>
        <h2>Preview</h2>
        <video id="preview" width="160" height="120" autoplay muted></video>
        </div>
        <div class="right">
        <div id="stopButton" class="button">
          Stop
        </div>
        <h2>Recording</h2>
        <video id="recording" width="160" height="120" controls></video>
        <a id="downloadButton" class="button">
          Download
        </a>
        </div>
        <div class="bottom">
        <pre id="log"></pre>
        </div>
    
        <script>
          let preview = document.getElementById("preview");
          let recording = document.getElementById("recording");
          let startButton = document.getElementById("startButton");
          let stopButton = document.getElementById("stopButton");
          let downloadButton = document.getElementById("downloadButton");
          let logElement = document.getElementById("log");
          
          let recordingTimeMS = 5000;
          function log(msg) {
            logElement.innerHTML += msg + "\n";
          }
          function wait(delayInMS) {
            return new Promise(resolve => setTimeout(resolve, delayInMS));
          }
          function startRecording(stream, lengthInMS) {
            let recorder = new MediaRecorder(stream);
            let data = [];
          
            recorder.ondataavailable = event => data.push(event.data);
            recorder.start();
            log(recorder.state + " for " + (lengthInMS/1000) + " seconds...");
          
            let stopped = new Promise((resolve, reject) => {
              recorder.onstop = resolve;
              recorder.onerror = event => reject(event.name);
            });
          
            let recorded = wait(lengthInMS).then(
              () => recorder.state == "recording" && recorder.stop()
            );
          
            return Promise.all([
              stopped,
              recorded
            ])
            .then(() => data);
          }
          function stop(stream) {
            stream.getTracks().forEach(track => track.stop());
          }
          startButton.addEventListener("click", function() {
            navigator.mediaDevices.getUserMedia({
              video: true,
              audio: true
            }).then(stream => {
              preview.srcObject = stream;
              downloadButton.href = stream;
              preview.captureStream = preview.captureStream || preview.mozCaptureStream;
              return new Promise(resolve => preview.onplaying = resolve);
            }).then(() => startRecording(preview.captureStream(), recordingTimeMS))
            .then (recordedChunks => {
              let recordedBlob = new Blob(recordedChunks, { type: "video/webm" });
              recording.src = URL.createObjectURL(recordedBlob);
              downloadButton.href = recording.src;
              downloadButton.download = "RecordedVideo.webm";
              
              log("Successfully recorded " + recordedBlob.size + " bytes of " +
                  recordedBlob.type + " media.");
            })
            .catch(log);
          }, false);stopButton.addEventListener("click", function() {
            stop(preview.srcObject);
          }, false);
        </script>
      </body>
    </html>