void InitEngine()
    {
        mRtcEngine = IRtcEngine.GetEngine(APP_ID);
        mRtcEngine.SetChannelProfile(CHANNEL_PROFILE.CHANNEL_PROFILE_LIVE_BROADCASTING);
        // If you want to user Multi Channel Video, please call "SetMultiChannleWant to true"
        mRtcEngine.SetMultiChannelWant(true);
        mRtcEngine.EnableAudio();
        mRtcEngine.EnableVideo();
        mRtcEngine.EnableVideoObserver();

        channel1 = mRtcEngine.CreateChannel(channel1Name);
        channel2 = mRtcEngine.CreateChannel(channel2Name);
        channel1.SetClientRole(CLIENT_ROLE_TYPE.CLIENT_ROLE_BROADCASTER);
        channel2.SetClientRole(CLIENT_ROLE_TYPE.CLIENT_ROLE_BROADCASTER);

        channel1.ChannelOnJoinChannelSuccess = Channel1OnJoinChannelSuccessHandler;
        channel1.ChannelOnLeaveChannel       = Channel1OnLeaveChannelHandler;
        channel1.ChannelOnUserJoined         = Channel1OnUserJoinedHandler;
        channel1.ChannelOnError = Channel1OnErrorHandler;
        channel2.ChannelOnJoinChannelSuccess = Channel2OnJoinChannelSuccessHandler;
        channel2.ChannelOnLeaveChannel       = Channel2OnLeaveChannelHandler;
        channel2.ChannelOnUserJoined         = Channel2OnUserJoinedHandler;
        channel2.ChannelOnError = Channel2OnErrorHandler;
    }