Avatar

Overview

Avatar (NaviusAvatar) is a single lookless Control folding the web contract’s three parts (Root/Fallback/Image) into one ControlTemplate that overlays a named PART_Image Image over a fallback region, switching visibility off a Status dependency property. Status (Idle/ Loading/Loaded/Error) is driven internally by Source changes and BitmapImage download events, and an optional DelayMs window suppresses the fallback from flashing during a fast load.

Usage

xmlns:navius="clr-namespace:Navius.Wpf.Primitives.Controls;assembly=Navius.Wpf.Primitives"

<navius:NaviusAvatar Source="https://example.com/avatar.png" DelayMs="200">
    <navius:NaviusAvatar.Fallback>
        <TextBlock Text="LZ" />
    </navius:NaviusAvatar.Fallback>
</navius:NaviusAvatar>

Properties

Property	Type	Default	From	Description
Source	string?	null	NaviusAvatar	Image URI/path. A (re)assigned non-empty value transitions Status to Loading until resolved via the BitmapImage download or the template Image’s ImageFailed.
DelayMs	int	0	NaviusAvatar	If <= 0, the fallback may render immediately; otherwise it waits DelayMs before the fallback is allowed to show.
Fallback	object?	null	NaviusAvatar	Content shown while IsFallbackVisible is true.
Status	NaviusAvatarLoadStatus	Idle	NaviusAvatar	Current load status (Idle/Loading/Loaded/Error). Normally driven internally by Source/image events; exposed as a public, settable dependency property (a deliberate deviation from the web’s internal-only status) for template triggers and tests.
IsFallbackVisible	bool	true	NaviusAvatar	Read-only. True when Status != Loaded and the DelayMs window (if any) has elapsed.

Events

Event	Signature	Fires when
LoadingStatusChanged	RoutedPropertyChangedEventHandler<NaviusAvatarLoadStatus>	Status transitions to a new value.

UIA mechanism

NaviusAvatar.cs has no OnCreateAutomationPeer() override, so no custom automation peer is created for this control; the web contract also wires no ARIA role or aria-* attribute on any Avatar part, so no specific UIA control-type parity is owed. Note: the parity doc’s own “WPF strategy” section proposed mapping the composite to an explicit FrameworkElementAutomationPeer (“plain ContentControl-level automation is sufficient”), but the shipped code does not add one; this is a parity-doc-vs-code gap worth flagging rather than a verified fact about the family’s runtime automation representation.

Web deltas

• The web’s three parts (NaviusAvatar/NaviusAvatarFallback/NaviusAvatarImage) fold into one lookless Control with a single named template part (PART_Image), not three separate CLR types.
• Status is exposed as a public, settable dependency property, unlike the web’s internal-only AvatarContext.Status setter.
• Load-state wiring is BitmapImage.DownloadCompleted/DownloadFailed plus the template Image’s ImageFailed routed event, the WPF async-image analog of the web’s native onload/onerror; WPF has no literal “ImageOpened” event, so DownloadCompleted stands in for it. A synchronous resolve (e.g. a pack/file URI with no async download) sets Status = Loaded directly when bitmap.IsDownloading is already false after EndInit().
• No data-state/status attribute is rendered anywhere in the web family either; the WPF port likewise adds no extra state marker beyond Status itself.

Captures

The Avatar Gallery page rendered at the pinned commit, in each theme.