PROSAGA码农传奇-webrtc-无法更改WebRTC呼叫的摄像头/流

<div class =“post-text”itemprop =“text”>
  
    以前我是按照以下方式完成的（订单很重要）。
  
  
    假设您列出了我们所有可用的设备：
  
   <pre>
 <code>
 var devicesIds = [];

navigator.mediaDevices.enumerateDevices().then(function(devices) {
  devices.forEach(function(device) {
     devicesIds.push(device.deviceId);
  });          
});

</code>
 </pre>
  
    现在你要切换：
  
  
    1）停止当前曲目
  
   <pre>
 <code>
 localStream.getTracks().forEach(function(track) {
 track.stop();
});

</code>
 </pre>
  
    2）获取新流
  
   <pre>
 <code>
 var constraints = {video: {deviceId: devicesIds[1]}, audio: true};

navigator.mediaDevices.getUserMedia(constraints).then(function(stream) {
  replaceTracks(stream);
}).catch(function(error) {

});

</code>
 </pre>
  
    3）替换曲目：
  
   <pre>
 <code>
 function replaceTracks(newStream){

detachMediaStream(elementId);

newStream.getTracks().forEach(function(track) {
     localStream.addTrack(track);
  });

attachMediaStream(elementId, newStream);

// optionally, if you have active peer connections:
  _replaceTracksForPeer(peerConnection);

function detachMediaStream = function(id) {
  var elem = document.getElementById(id);

if (elem) {
    elem.pause();

if (typeof elem.srcObject === 'object') {
        elem.srcObject = null;
    } else {
        elem.src = '';
    }
  }
};

function attachMediaStream = function(id, stream) {
  var elem = document.getElementById(id);

if (elem) {
    if (typeof elem.srcObject === 'object') {
        elem.srcObject = stream;
    } else {
        elem.src = window.URL.createObjectURL(stream);
    }

elem.onloadedmetadata = function(e) {
        elem.play();
    };
  } else {
    throw new Error('Unable to attach media stream');
  }
};

</code>
 </pre>
</DIV>