ListenTogether V2.2 API

ListenTogether is a .NET 9.0 library for synchronized listening parties. This document covers all public APIs.

ListenTogetherClient

The core class for communicating with the Central Server.

Constructor

public ListenTogetherClient()

Creates a new client instance connected to the ListenTogether Central Server.

Properties

Property	Type	Description
`IsConnected`	`bool`	Whether currently connected to server
`IsHost`	`bool`	Whether current user is party host
`IsHostOnlyMode`	`bool`	Whether party is in host-only control mode
`CanControl`	`bool`	Whether user can control playback
`Reconnection`	`ReconnectionOptions`	Settings for automatic reconnection

Party Management Methods

SetUserProfile

public void SetUserProfile(string nickname)

Sets and saves the user's nickname (1-50 characters).

CreatePartyAsync

public Task<string> CreatePartyAsync(bool isHostOnlyMode)

Creates a new party session. Returns the generated PIN (e.g., "ABCD-1234").

JoinPartyAsync

public Task JoinPartyAsync(string pin)

Requests to join a party. Wait for OnJoinApproved event.

ApproveUserAsync

public Task ApproveUserAsync(string socketId, bool approved)

(Host only) Approves or rejects a join request.

DisbandPartyAsync

public Task DisbandPartyAsync()

(Host only) Ends the party for everyone.

Playback Control Methods

Note: Throws InvalidOperationException in host-only mode when called by non-host.

UpdateStateAsync

public Task UpdateStateAsync(PartyState state)

Broadcasts playback state update.

SeekToAsync

public Task SeekToAsync(TimeSpan position)

Seeks to a specific position. Broadcasts to all clients.

SendHeartbeatAsync

public Task SendHeartbeatAsync(double positionMs, bool isPlaying)

Sends current position for sync correction.

SignalTrackFinishedAsync

public Task SignalTrackFinishedAsync()

Notifies server that current track finished.

Queue Management Methods

UpdateQueueAsync

public Task UpdateQueueAsync(string action, Track track)

Adds or removes a track. Action: "add" or "remove".

MoveQueueItemAsync

public Task MoveQueueItemAsync(int fromIndex, int toIndex)

Moves a track within the queue.

ClearQueueAsync

public Task ClearQueueAsync()

Removes all tracks from queue.

ShuffleQueueAsync

public Task ShuffleQueueAsync()

Randomly shuffles the queue.

Playback Mode Methods

SetRepeatModeAsync

public Task SetRepeatModeAsync(RepeatMode mode)

Sets repeat mode: Off, One, or All.

SetShuffleAsync

public Task SetShuffleAsync(bool enabled)

Enables or disables shuffle mode.

Events

Party Events

Event	Description
`OnUserJoined`	User joined (includes username)
`OnUserLeft`	User left (includes username)
`OnUserRequestingJoin`	(Host) User wants to join
`OnJoinApproved`	Join request approved
`OnPartyDisbanded`	Party ended by host

ReconnectionOptions

public class ReconnectionOptions
                    {
                    public bool Enabled { get; set; } = true;
                    public int MaxRetries { get; set; } = 5;
                    public int BaseDelayMs { get; set; } = 500;
                    public int MaxDelayMs { get; set; } = 30000;
                    public bool AutoRejoinParty { get; set; } = true;
                    }

Uses exponential backoff: 500ms -> 1s -> 2s -> 4s -> ... -> max 30s.

ListenTogetherViewModel

MVVM ViewModel using CommunityToolkit.Mvvm.

Observable Properties

Property	Type	Description
`ConnectionState`	`ConnectionState`	Current connection state
`Nickname`	`string`	User's nickname
`Pin`	`string`	Current party PIN
`TargetPin`	`string`	PIN to join
`StatusMessage`	`string`	Human-readable status
`IsHost`	`bool`	Is party host
`IsHostOnlyMode`	`bool`	Host-only mode enabled
`CanControl`	`bool`	Can control playback
`CurrentTrack`	`Track?`	Now playing
`IsPlaying`	`bool`	Playback active
`CurrentPositionMs`	`double`	Position in ms
`RepeatMode`	`RepeatMode`	Current repeat mode
`IsShuffleEnabled`	`bool`	Shuffle enabled

Collections

Property	Type	Description
`Queue`	`ObservableCollection<Track>`	Track queue
`Users`	`ObservableCollection<ListenTogetherUser>`	Party members
`PendingRequests`	`ObservableCollection<ListenTogetherUser>`	Join requests (host)

Models

public class Track
                    {
                    public string SongTitle { get; set; }
                    public string SongId { get; set; }
                    public string ArtistName { get; set; }
                    public string AlbumName { get; set; }
                    public TimeSpan SongDuration { get; set; }
                    public string ArtworkUrl { get; set; }
                    public string SourceType { get; set; }
                    }

Socket.IO Protocol

The client uses standard Socket.IO events to communicate. See source for full event list.