Notifications & Dialogs

Overview

The Notification, StatusBar, and Dialog controls provide Material Design 3.0 messaging and overlay feedback entirely rendered with SkiaSharp. Notification (toast/snackbar) displays transient messages at a configurable screen position with automatic dismissal. StatusBar is a persistent bottom strip for status information, progress, and quick actions. Dialog renders a modal overlay with a title, body content, and action buttons, blocking interaction with the canvas beneath until dismissed.

All overlay components are managed by the OverlayManager, which handles z-ordering, focus trapping (for dialogs), and dismiss-on-escape behavior. Notifications and dialogs use enter/exit animations following MD3 motion guidelines.

Notification Properties

StatusBar & StatusBarItem

The StatusBar is a persistent horizontal strip typically rendered at the bottom of the canvas. It contains StatusBarItem children that display text, icons, or progress indicators.

StatusBarItem

Dialog Support

The Dialog control renders a modal overlay dialog following MD3 dialog specifications. A semi-transparent scrim covers the canvas behind the dialog, and pointer events outside the dialog bounds are intercepted to enforce modality.

Notification Types

The accent color tints the leading icon and the left border of the notification surface. The background is always InverseSurface with InverseOnSurface text for high contrast.

Code Example

var notification = new Notification
{
    Message = "Project saved successfully.",
    Type = NotificationType.Success,
    Duration = 3000,
    Position = NotificationPosition.Bottom,
    ShowProgress = true
};

notification.ActionClicked += (s, action) =>
    Console.WriteLine($"Action: {action}");

notification.Initialize();
notification.Show();

drawingManager.RequestRedraw();

var snackbar = new Notification
{
    Message = "Item deleted.",
    Type = NotificationType.Info,
    Duration = 5000,
    Position = NotificationPosition.Bottom,
    ActionText = "Undo",
    ShowProgress = true
};

snackbar.Initialize();

snackbar.ActionClicked += (s, action) =>
{
    if (action == "Undo")
    {
        RestoreDeletedItem();
    }
};

snackbar.Show();

var statusBar = new StatusBar
{
    X = 0, Y = 0,
    Width = 800,
    BarHeight = 28,
    Items = new List<StatusBarItem>
    {
        new() { Text = "Ready", Icon = null, Width = 120 },
        new() { Text = "", Width = 0 },
        new() { Text = "Ln 24, Col 12", Alignment = StatusAlignment.Right, Width = 140 },
        new() { Text = "UTF-8", Alignment = StatusAlignment.Right, Width = 80 },
        new() { Text = "100%", Alignment = StatusAlignment.Right, Width = 60 }
    }
};

statusBar.Initialize();
drawingManager.AddComponent(statusBar);
drawingManager.RequestRedraw();

var cancelButton = new Button
{
    Text = "Cancel",
    ButtonStyle = ButtonStyle.Text,
    Width = 80, Height = 40,
    Tag = "cancel"
};

var confirmButton = new Button
{
    Text = "Delete",
    ButtonStyle = ButtonStyle.Filled,
    Width = 80, Height = 40,
    Tag = "confirm"
};

cancelButton.Initialize();
confirmButton.Initialize();

var dialog = new Dialog
{
    Title = "Delete Project?",
    Body = "This action cannot be undone. All associated files and configurations will be permanently removed.",
    Buttons = new List<Button> { cancelButton, confirmButton },
    IsModal = true,
    MaxWidth = 480
};

dialog.Initialize();

dialog.ActionClicked += (s, tag) =>
{
    if (tag == "confirm")
    {
        DeleteProject();
        ShowNotification("Project deleted.", NotificationType.Success);
    }
    dialog.Close();
};

dialog.Open();
drawingManager.RequestRedraw();

var errorNotification = new Notification
{
    Message = "Failed to connect to database.\nCheck your connection settings and try again.",
    Type = NotificationType.Error,
    Duration = 0,
    Position = NotificationPosition.TopRight,
    IsDismissible = true,
    ActionText = "Retry"
};

errorNotification.Initialize();

errorNotification.ActionClicked += (s, action) =>
{
    if (action == "Retry") RetryConnection();
};

errorNotification.Show();

public static class NotificationManager
{
    public static void ShowInfo(string message, string actionText = null,
        Action action = null)
    {
        Show(message, NotificationType.Info, actionText, action);
    }

    public static void ShowSuccess(string message)
    {
        Show(message, NotificationType.Success);
    }

    public static void ShowError(string message, string actionText = null,
        Action action = null)
    {
        Show(message, NotificationType.Error, actionText, action, duration: 0);
    }

    private static void Show(string message, NotificationType type,
        string actionText = null, Action action = null, float duration = 4000)
    {
        var notification = new Notification
        {
            Message = message,
            Type = type,
            Duration = duration,
            Position = NotificationPosition.Bottom,
            ActionText = actionText
        };
        notification.Initialize();

        if (actionText != null && action != null)
            notification.ActionClicked += (s, a) => action();

        notification.Show();
    }
}