Stream Chat Flutter SDK

In the redesigned composer, slow mode is a highly visible state. When slow mode is active for the user:

• The text input is disabled (enabled: false).
• The trailing send button is replaced by a disabled countdown button showing the remaining seconds.
• The placeholder displays a live countdown (e.g., Slow mode, wait 9s…).

Precedence Note: Slow mode now has the highest precedence. If slow mode is active, its placeholder will be shown even if a command or attachment is present.

To restore the old behavior (where the input remained editable during slow mode), you must override placeholderBuilder and provide a custom trailing component via streamChatComponentBuilders(messageComposerInputTrailing: ...).

Localization: The default countdown text uses Translations.slowModeOnLabel(int cooldownTimeOut).

The MessageInputPlaceholder sealed class provides contextual data for different input states. When implementing placeholderBuilder, you can pattern-match on these cases to access specific metadata:

Note: Using a switch expression on this sealed class ensures compile-time safety; if the SDK adds new placeholder types, your code will fail to compile until you handle the new case.

When StreamChatCore mounts, it sets client.recoverStateOnReconnect = false. While the SDK's built-in list controllers (like StreamChannelListController) handle their own refreshes automatically, any Channel you watch manually (outside of a list controller) will not automatically refresh on reconnection.

To ensure manually watched channels stay up to date, you must subscribe to EventType.connectionRecovered and call channel.watch() manually.

If you need to restore the old behavior where the client automatically recovers state, set client.recoverStateOnReconnect = true after mounting.

late final StreamSubscription _sub;

@override
void initState() {
  super.initState();
  _sub = client.on(EventType.connectionRecovered).listen((_) {
    channel.watch();
  });
}

@override
void dispose() {
  _sub.cancel();
  super.dispose();
}

The redesigned UI components are split into two distinct layers to separate product-agnostic UI primitives from chat-specific logic:

1. stream_core_flutter: Contains product-agnostic primitives like avatars, badges, buttons, sheets, app bars, and theming tokens. These classes do not depend on chat-domain models like Channel, Message, or User.
2. stream_chat_flutter: Contains chat-domain wrappers. These components take chat models and delegate the actual visual rendering to the primitives in the core layer.

Note on Imports: Most core types are re-exported from stream_chat_flutter. You can usually continue using package:stream_chat_flutter/stream_chat_flutter.dart for most imports, even if a type has been moved to the core layer.

The SDK provides two distinct composer components with different responsibilities:

1. StreamMessageComposer: A full-featured widget that handles all business logic, including sending, editing, attachments, autocomplete, mentions, commands, OG previews, and the voice recording flow. Use this for standard chat implementations.
2. StreamChatMessageInput: A UI-only component that renders the composer layout using design system primitives. It contains no business logic. Use this if you want to implement your own custom message-sending logic while maintaining the new design system's visual style.

StreamMessageComposer wraps StreamChatMessageInput for its visual layer and is not deprecated.

In v10.0.0, StreamMessageComposerInput was split into two distinct roles. If you want to customize only the text field area (the center content), you must now target StreamMessageComposerInputCenter using the messageComposerInputCenter builder key. Targeting StreamMessageComposerInput will replace the entire input row (including leading/trailing elements).

// To replace only the text field area:
// Use StreamMessageComposerInputCenter and the 'messageComposerInputCenter' builder key.

// To replace the entire input row:
// Use StreamMessageComposerInput and the 'messageComposerInput' builder key.

List-view state (pagination, filtering, refreshing) is managed by controllers that extend PagedValueNotifier<Key, Value> from stream_chat_flutter_core.

Lifecycle Rule: Callers (the users of the widgets) own the controller lifecycle. You are responsible for creating, passing, and disposing of the controller. Widgets should generally not construct controllers internally unless they are strictly internal to the widget's logic.

// Examples of available controllers:
// - StreamChannelListController
// - StreamMessageListController
// - StreamUserListController
// - StreamMemberListController
// - StreamThreadListController
// - StreamDraftListController
// - StreamPollController
// - StreamMessageReminderListController