Toast / ToastManager

ToastManager displays transient ToastMessage notification cards over a host element using the WPF adorner layer. Toasts can auto-dismiss after a duration or stay open until closed, support success/info/warning/error severities, and can be positioned in any corner of the host surface.

Basic usage

Create a manager for the element that should host the toast overlay:

private ToastManager? _toastManager;

private void OnLoaded(object sender, RoutedEventArgs e)
{
    _toastManager ??= new ToastManager(this);
}

Show a timed toast:

_toastManager.Show(
    "Saved",
    "Your changes were saved.",
    ToastSeverity.Success,
    TimeSpan.FromSeconds(4),
    ToastQuadrant.BottomRight);

Show a persistent toast with a close button by passing null for the duration:

var toast = _toastManager.Show(
    "Connection lost",
    "Reconnect when the network is available.",
    ToastSeverity.Warning,
    null,
    ToastQuadrant.TopRight);

toast.Dismissed += (_, e) =>
{
    // e.Reason is Timeout, ClosedByUser, or Programmatic.
};

For an application-wide instance, initialize the default manager once over a root element:

ToastManager.Initialize(MainGrid);
ToastManager.Default?.Show("Ready", "Notifications are enabled.");

Key members

Member	Description
ToastManager.Initialize(UIElement adornedElement)	Creates ToastManager.Default over a host element.
ToastManager.Show(...)	Creates and displays a ToastMessage. Returns the toast so callers can listen for dismissal or dismiss it manually.
ToastManager.DismissAll()	Dismisses every open toast managed by the instance.
ToastManager.ActiveCount	Number of currently displayed toasts.
ToastManager.ToastShown	Raised when a toast is shown.
ToastManager.AllDismissed	Raised after the last open toast has been dismissed.
ToastMessage.Dismiss(...)	Dismisses a toast programmatically.
ToastMessage.Dismissed	Raised once when the toast finishes dismissing.

Options

Type	Values
ToastSeverity	Success, Info, Warning, Error
ToastQuadrant	TopLeft, TopRight, BottomLeft, BottomRight
ToastDismissReason	Timeout, ClosedByUser, Programmatic

The host element must be loaded and beneath an AdornerDecorator; normal WPF window content satisfies this by default.