Manage Participants - Android

1. Local Participant (self)

Local participant is used to consume your video & audio streams. it contains information about local participant such as displayName, id, quality and streams Map.

You can acces localParticipant from the meeting object.

Participant object properties

Property Name	Type	Description
id	string	Unique id of the participant.
displayName	string	The name you define during the meeting initialization.
local	boolean	Indicates the participant is local or not.
quality	string	Indicates the participant streams quality.
Streams	Map of Stream	Returns Video & Audio Streams.

Stream Object properties

Property Name	Type	Description
id	string	Unique id
codec	string	Video/Audio codec.
kind	string	Stream Kind.
track	string	MediaStreamTrack

2. Other Participants (Except You)

Other participants Map is used to get all the participants (except you) in the meeting at any given time.

Other participants Map contains same properties as LocalParticipant.

Local And Other Participants

activity_main.xml

  <org.webrtc.SurfaceViewRenderer
      android:id="@+id/svrLocal"
      android:layout_width="80dp"
      android:layout_height="100dp"
      android:layout_gravity="end" />

  <androidx.recyclerview.widget.RecyclerView
      android:id="@+id/rvParticipants"
      android:layout_width="match_parent"
      android:layout_height="match_parent" />

Kotlin

MainActivity.kt

  import org.webrtc.SurfaceViewRenderer;
  import org.webrtc.VideoTrack;

  private fun displayLocalParticipant() {
    var svrLocal: SurfaceViewRenderer = findViewById(R.id.btnScreenShare)

    // display local video when stream available
    meeting!!.localParticipant.addEventListener(
       object : ParticipantEventListener() {
         override fun onStreamEnabled(stream: Stream) {
           if (stream.kind.equals("video", ignoreCase = true)) {
             val videoTrack = stream.track as VideoTrack
             videoTrack.addSink(svrLocal)
            }
         }
      }
    )
  }

  private fun displayRemoteParticipants() {
    val rvParticipants = findViewById<RecyclerView>(R.id.rvParticipants)
    rvParticipants.layoutManager = GridLayoutManager(this, 2)
    rvParticipants.adapter = ParticipantAdapter(meeting!!)
  }

Java

MainActivity.java

  import org.webrtc.SurfaceViewRenderer;
  import org.webrtc.VideoTrack;

  private void displayLocalParticipant() {
    final SurfaceViewRenderer svrLocal = findViewById(R.id.svrLocal);

    // display local video when stream available
    meeting.getLocalParticipant().addEventListener(
        new ParticipantEventListener() {
          @Override
          public void onStreamEnabled(Stream stream) {
            if (stream.getKind().equalsIgnoreCase("video")) {
              VideoTrack track = (VideoTrack) stream.getTrack();
              track.addSink(svrLocal);
            }
          }
        }
      );
  }

  private void displayRemoteParticipants() {
    final RecyclerView rvParticipants = findViewById(R.id.rvParticipants);
    rvParticipants.setLayoutManager(new GridLayoutManager(this, 2));
    rvParticipants.setAdapter(new ParticipantAdapter(meeting));
  }

item_remote_peer.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <org.webrtc.SurfaceViewRenderer
        android:id="@+id/svrParticipant"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

</FrameLayout>

Kotlin

ParticipantAdapter.kt

class ParticipantAdapter(meeting: Meeting) : RecyclerView.Adapter<ParticipantAdapter.PeerViewHolder>() {
    private val participants: MutableList<Participant> = ArrayList()
    private var containerHeight = 0

    init {
        participants.add(meeting.localParticipant)
        meeting.addEventListener(object : MeetingEventListener() {
            override fun onParticipantJoined(participant: Participant) {
                participants.add(participant)
                notifyItemInserted(participants.size - 1)
            }

            override fun onParticipantLeft(participant: Participant) {
                // remove participant from grid
            }
        })
    }

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): PeerViewHolder {
        containerHeight = parent.height
        return PeerViewHolder(
            LayoutInflater.from(parent.context)
                .inflate(R.layout.item_remote_peer, parent, false)
        )
    }

    override fun onBindViewHolder(holder: PeerViewHolder, position: Int) {
        val participant = participants[position]

        val layoutParams = holder.itemView.layoutParams
        layoutParams.height = containerHeight / 3
        holder.itemView.layoutParams = layoutParams

        for ((_, stream) in participant.streams) {
            if (stream.kind.equals("video", ignoreCase = true)) {
                val videoTrack = stream.track as VideoTrack
                videoTrack.addSink(holder.svrParticipant)
                break
            }
        }

        participant.addEventListener(object : ParticipantEventListener() {
            override fun onStreamEnabled(stream: Stream) {
                if (stream.kind.equals("video", ignoreCase = true)) {
                    val videoTrack = stream.track as VideoTrack
                    videoTrack.addSink(holder.svrParticipant)
                }
            }
        })
    }

    override fun getItemCount(): Int {
        return participants.size
    }

    class PeerViewHolder(view: View) : RecyclerView.ViewHolder(view) {
        var svrParticipant: SurfaceViewRenderer = view.findViewById(R.id.svrParticipant)
        init{
            svrParticipant.init(PeerConnectionUtils.getEglContext(), null)
        }
    }
}

Please refer the example code on Github for more details.

Java

ParticipantAdapter.java

public class ParticipantAdapter extends RecyclerView.Adapter<ParticipantAdapter.PeerViewHolder> {

    private final List<Participant> participants = new ArrayList<>();
    private int containerHeight;

    public ParticipantAdapter(Meeting meeting) {
        Handler mHandler = new Handler(Looper.getMainLooper());

        meeting.addEventListener(new MeetingEventListener() {
            @Override
            public void onParticipantJoined(Participant participant) {
                participants.add(participant);
                mHandler.post(() -> notifyItemInserted(participants.size() - 1));
            }

            @Override
            public void onParticipantLeft(Participant participant) {
                // remove participant from grid
            }
        });
    }

    @NonNull
    @Override
    public PeerViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        containerHeight = parent.getHeight();

        return new PeerViewHolder(LayoutInflater.from(parent.getContext())
                .inflate(R.layout.item_remote_peer, parent, false));
    }

    @Override
    public void onBindViewHolder(@NonNull PeerViewHolder holder, int position) {
        final Participant participant = participants.get(position);

        ViewGroup.LayoutParams layoutParams = holder.itemView.getLayoutParams();
        layoutParams.height = containerHeight / 3;
        holder.itemView.setLayoutParams(layoutParams);

        for (Map.Entry<String, Stream> entry : participant.getStreams().entrySet()) {
            Stream stream = entry.getValue();
            if (stream.getKind().equalsIgnoreCase("video")) {
                VideoTrack videoTrack = (VideoTrack) stream.getTrack();
                videoTrack.addSink(holder.svrParticipant);
                break;
            }
        }

        participant.addEventListener(new ParticipantEventListener() {
            @Override
            public void onStreamEnabled(Stream stream) {
                if (stream.getKind().equalsIgnoreCase("video")) {
                    VideoTrack videoTrack = (VideoTrack) stream.getTrack();
                    videoTrack.addSink(holder.svrParticipant);
                }
            }
        });

    }

    @Override
    public int getItemCount() {
        return participants.size();
    }

    static class PeerViewHolder extends RecyclerView.ViewHolder {
        public SurfaceViewRenderer svrParticipant;
        public View itemView;

        PeerViewHolder(@NonNull View view) {
            super(view);

            itemView = view;

            svrParticipant = view.findViewById(R.id.svrParticipant);
            svrParticipant.init(PeerConnectionUtils.getEglContext(), null);
        }
    }
}

Please refer the example code on Github for more details.

3. Participant Related Events

1. onParticipantJoined - Whenever any new participant join the meeting, onParticipantJoined event will trigger. For example, the meeting is running with Alice and Bob, then Eve join that meeting, after that onParticipantJoined event trigger and return the participant object.

2. onParticipantLeft - Whenever any participant leave/exit the meeting, onParticipantLeft event will trigger.For example, the meeting is running with Alice and Bob, then Bob leave that meeting, after that onParticipantLeft event trigger and return the participant object

3. onPresenterChanged - Whenever any participant present/screenshare their screen/window in meeting, onPresenterChanged event will trigger and return the presenter participantId.

4. onStreamEnabled - Whenever any participant enabled mic/webcam in meeting, onStreamEnabled event will trigger and return Stream.

5. onStreamDisabled - Whenever any participant disabled mic/webcam in meeting, onStreamDisabled event will trigger and return Stream.

Kotlin

 meeting.addEventListener(object : MeetingEventListener() {
    override fun onParticipantJoined(participant: Participant) {
        participant.addEventListener(object : ParticipantEventListener() {
                override fun onStreamEnabled(stream: Stream) {
                    if (stream.kind.equals("video", ignoreCase = true)) {
                         // participant video enabled
                    } else if (stream.kind.equals("audio", ignoreCase = true)) {
                         // participant mic enabled
                    }
                }
                override fun onStreamDisabled(stream: Stream) {
                    if (stream.kind.equals("video", ignoreCase = true)) {
                         // participant video disabled
                    } else if (stream.kind.equals("audio", ignoreCase = true)) {
                        // participant mic disabled
                    }
                }
        })
    }

    override fun onParticipantLeft(participant: Participant) {
        Toast.makeText(this@MainActivity, participant.displayName + " left", Toast.LENGTH_SHORT).show()
    }

    override fun onPresenterChanged(presenterId: String) {
        Toast.makeText(this@MainActivity, presenterId + " started presenting", Toast.LENGTH_SHORT).show()
    }
 })

Java

 meeting.addEventListener(new MeetingEventListener() {
    @Override
    public void onParticipantJoined(Participant participant) {
      participant.addEventListener(new ParticipantEventListener() {
          @Override
          public void onStreamEnabled(Stream stream) {
              if (stream.getKind().equalsIgnoreCase("video")) {
                  // participant video enabled
              } else if (stream.getKind().equalsIgnoreCase("audio")) {
                  // participant mic enabled
              }
          }

          @Override
          public void onStreamDisabled(Stream stream) {
              if (stream.getKind().equalsIgnoreCase("video")) {
                  // participant video disabled
              } else if (stream.getKind().equalsIgnoreCase("audio")) {
                  // participant mic disabled
              }
          }
      });
    }

    @Override
    public void onParticipantLeft(Participant participant) {
      Toast
        .makeText(
          MainActivity.this,
          participant.getDisplayName() + " left",
          Toast.LENGTH_SHORT
        )
        .show();
    }
    @Override
    public void onPresenterChanged(String presenterId) {
      Toast
        .makeText(
          MainActivity.this,
          presenterId + " started presenting",
          Toast.LENGTH_SHORT
        )
        .show();
    }
 });