ChatWindow

Message display area for the chat UI. Binds to a ChatChannel, listens for new messages, and delegates rendering to a ChatScrollRect. Manages background visibility with animated fade transitions tied to the ChatHUD focus state.

Definition

Namespace: Paragon.Townskeep.ChatSystem.HUD Assembly: Townskeep.dll

public class ChatWindow : ParagonUIBehaviour

Inheritance: SerializedMonoBehaviour → ParagonBehaviour → ParagonUIBehaviour → ChatWindow

Remarks

ChatWindow is the bridge between the data model (ChatChannel) and the virtualized display (ChatScrollRect). When a channel is set via SetChannel(), the window:

1. Unsubscribes from the previous channel's MessageSent event

2. Clears the scroll rect

3. Subscribes to the new channel's MessageSent event

4. Pushes all existing messages to the scroll rect

Focus-Driven Background Fade

The window has a background CanvasGroup (found via transform.Find("Background")) that fades in/out based on the ChatHUD focus state:

• On focus — Fades background alpha to 1.0 over 1.5s via DOTween

• On unfocus — Waits 2.0s (via Yield.WaitForSeconds), then fades to 0.0 over 1.5s if the chat is still unfocused

The background starts hidden (alpha = 0) in Awake().

Message Access

ChatWindow exposes GetMessage(Index) and GetAllMessages() which delegate directly to the bound ChatChannel. These are used by ChatScrollRect during virtualized line cycling.

Quick Lookup

Goal	How
Initialize	window.Initialize(chatHUD)
Switch to a channel	window.SetChannel(channel)
Get a message by index	window.GetMessage(^1) (newest)
Get all messages	window.GetAllMessages()
Read message count	window.MessageCount
Read active channel	window.Channel

Properties

Property	Type	Description
ID	int	Window identifier
Name	string	Name of the currently bound channel (null-safe)
Channel	ChatChannel	The currently bound chat channel
MessageCount	int	Number of messages in the current channel (0 if no channel bound)

Methods

Initialize

Sets up the window with its parent ChatHUD. Initializes the child ChatScrollRect and subscribes to focus/unfocus events for background fading.

public void Initialize(ChatHUD chatHUD)

Parameter	Type	Description
chatHUD	ChatHUD	The parent chat HUD coordinator

SetChannel

Switches the window to display messages from a different chat channel. Clears existing messages and loads the new channel's history.

public void SetChannel(ChatChannel channel)

Parameter	Type	Description
channel	ChatChannel	The channel to bind to (can be null to unbind)

Behavior:

1. Unsubscribes OnMessageSent from the previous channel (if any)

2. Clears the scroll rect

3. If channel is not null: subscribes to MessageSent and pushes all existing messages

GetMessage

Retrieves a message from the current channel by index. Supports C# Index with hat (^) operator for reverse indexing.

public ChatMessage GetMessage(Index index)

Parameter	Type	Description
index	Index	Message index (e.g., ^1 for newest)

Returns: The ChatMessage at the specified index.

GetAllMessages

Returns all messages from the current channel, or an empty enumerable if no channel is bound.

public IEnumerable<ChatMessage> GetAllMessages()

Returns: All messages in the channel, or Enumerable.Empty<ChatMessage>() if channel is null.

Common Pitfalls

Background child must be named "Background" The background CanvasGroup is found via transform.Find("Background"). If the child GameObject is named differently, a NullReferenceException occurs in Awake().

SetChannel(null) leaves the window in an unbound state Passing null clears the scroll rect and unsubscribes from events, but MessageCount returns 0 and GetAllMessages() returns empty. GetMessage() will throw because channel is null.

Unfocus fade has a 2-second async delay OnUnfocus() uses await Yield.WaitForSeconds(2.0f) before fading. If Focus() is called during this delay, the IsFocused check on chatHUD prevents the fade. However, the async void method is still running — rapid focus/unfocus cycles will accumulate pending coroutines.

OnDestroy unsubscribes from events The window properly unsubscribes from chatHUD.OnFocus, chatHUD.OnUnfocus, and channel.MessageSent in OnDestroy(). If chatHUD is destroyed first, the null check prevents errors.

See Also

• ChatScrollRect — virtualized scroll view that renders messages

• ChatTab — triggers channel switching via ChatTabs.SelectTab()

• ChatTabs — tab bar that calls SetChannel() on selection

• ChatHUD — root coordinator providing focus events

• Chat Overview — system architecture