StreamSnackbarMessenger class

Imperative owner of a snackbar queue.

One StreamSnackbarMessenger backs one rendering surface: hand it to a StreamSnackbarHost or StreamSnackbarPopup and call show to enqueue. If another snackbar is already visible, the new call waits its turn behind it.

Dispose when no longer needed.

{@tool snippet}

Manual ownership:

final messenger = StreamSnackbarMessenger();
final controller = messenger.show(const StreamSnackbar(
  message: Text('Message deleted'),
  variant: StreamSnackbarVariant.success,
  action: StreamSnackbarAction(label: Text('Undo'), onPressed: undo),
));

{@end-tool}

See also:

• StreamSnackbarHost, renders snackbars from this state inline.
• StreamSnackbarPopup, anchored variant for small surfaces.
• StreamSnackbarScope, a convenience that owns a state and host.

Inheritance

• Object
• ChangeNotifier
• StreamSnackbarMessenger

Constructors

StreamSnackbarMessenger()

Creates an empty messenger.

Properties

currentController → StreamSnackbarController?

The controller for the currently-displayed snackbar, or null if none.

no setter

currentSnackbar → StreamSnackbar?

The StreamSnackbar currently being displayed, or null if none.

no setter

hashCode → int

The hash code for this object.

no setter, inherited

hasListeners → bool

Whether any listeners are currently registered.

no setter, inherited

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

Methods

addListener(VoidCallback listener) → void

Register a closure to be called when the object changes.

inherited

clearSnackbars() → void

Removes every snackbar — current and queued — without animation.

dispose() → void

Discards any resources used by the object.

override

hideCurrent([StreamSnackbarClosedReason reason = .dismiss]) → void

Dismisses the currently-displayed snackbar with the exit animation. No-op when the queue is empty.

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

notifyListeners() → void

Call all the registered listeners.

inherited

removeCurrent([StreamSnackbarClosedReason reason = .remove]) → void

Dismisses the currently-displayed snackbar without an exit animation and immediately advances to the next queued one. No-op when the queue is empty.

removeListener(VoidCallback listener) → void

Remove a previously registered closure from the list of closures that are notified when the object changes.

inherited

show(StreamSnackbar snackbar, {bool replace = false}) → StreamSnackbarController

Enqueues snackbar for display.

toString() → String

A string representation of this object.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited

Static Methods

maybeOf(BuildContext context) → StreamSnackbarMessenger?

Returns the nearest StreamSnackbarMessenger ancestor, or null if none is found.

of(BuildContext context) → StreamSnackbarMessenger

Returns the nearest StreamSnackbarMessenger ancestor provided by a StreamSnackbarHost, StreamSnackbarPopup, or StreamSnackbarScope.