Tutorial: Handle Device Change

Function Description

This article mainly introduces how to detect the behavior of users inserting, unplugging, and starting devices. And how to handle device collection exceptions.

About SDK automatic recovery collection
The SDK will detect the insertion and removal behavior of the camera and microphone, and automatically recover the collection at the appropriate time. The specific logic is as follows:

1. If the currently streaming camera/microphone is unplugged, the SDK will try to use the remaining available media devices to restore the collection.
2. If the camera/microphone is unplugged and there are no available media devices, the SDK will detect the device insertion behavior. If a new available media device is inserted, the SDK will try to use the newly inserted media device to restore the collection and push the stream.
3. If the recovery fails, an error TRTC.ERROR_CODE.DEVICE_ERROR will be thrown, and the extraCode will be 5308 and 5309.

Implementation Process

Detect device insertion, removal, and startup

trtc.on(TRTC.EVENT.DEVICE_CHANGED, (event) => {
  // Device insertion
  if (event.action === 'add') {
    // Camera insertion
    if (event.type === 'camera') {}
  } else if (event.action === 'remove') {
    // Device unplugged
  } else if (event.action === 'active') {
    // Device startup
  }
  console.log(`${event.type}(${event.device.label}) ${event.action}`);
});

Check if the currently used device is unplugged

trtc.on(TRTC.EVENT.DEVICE_CHANGED, (event) => {
  if (event.action === 'remove') {
    if (event.type === 'camera') {
      const currentCameraId = trtc.getVideoTrack()?.getSettings()?.deviceId;
      if (event.device.deviceId === currentCameraId) {
        // The currently used camera is unplugged.
      }
    } else if (event.type === 'microphone') {
      const currentMicId = trtc.getAudioTrack()?.getSettings()?.deviceId;
      if (event.device.deviceId === currentMicId) {
        // The currently used microphone is unplugged.
      }
    }
  }
});

Automatically switch to using new devices when users insert new devices.

trtc.on(TRTC.EVENT.DEVICE_CHANGED, (event) => {
  if (event.action === 'add') {
    if (event.type === 'camera') {
      // After inserting the camera, automatically switch to the new camera
      trtc.updateLocalVideo({ option: { cameraId: event.device.deviceId }});
    }
  }
});

Handling device collection exceptions

Listen for device collection exception events

trtc.on(TRTC.EVENT.VIDEO_PLAY_STATE_CHANGED, event => {
  // Local camera collection exception, at this time the SDK will try to automatically recover the collection, you can guide the user to check whether the camera is normal.
  if (event.userId === '' && event.streamType === TRTC.TYPE.STREAM_TYPE_MAIN && (event.reason === 'mute' || event.reason === 'ended')) {}
});
trtc.on(TRTC.EVENT.AUDIO_PLAY_STATE_CHANGED, event => {
  // Local microphone collection exception, at this time the SDK will try to automatically recover the collection, you can guide the user to check whether the microphone is normal.
  if (event.userId === '' && (event.reason === 'mute' || event.reason === 'ended')) {}
});

Listen for SDK automatic recovery collection failure events

trtc.on(TRTC.EVENT.ERROR, error => {
  if (error.code === TRTC.ERROR_CODE.DEVICE_ERROR) {
    // Camera recovery collection failed
    if (error.extraCode === 5308) {
      // After guiding the user to check the device, call updateLocalVideo and pass in cameraId to recollect.
      trtc.updateLocalVideo({ option: { cameraId: '' }});
    }
    // Microphone recovery collection failed
    if (error.extraCode === 5309) {
      // After guiding the user to check the device, call updateLocalAudio and pass in microphoneId to recollect.
      trtc.updateLocalAudio({ option: { microphoneId: '' }});
    }
  }
})