Developer preview

Mark static methods with [UiPreview] and Developer Tools renders your view in states that are hard to reach live.

Example

using MacroDeck.Ui.Dsl;
using MacroDeck.Ui.Previews;

internal static class WeatherViewPreviews
{
    [UiPreview("Sunny", Profile = UiPreviewProfiles.Widget)]
    public static UiElement Sunny() => WeatherView.Build(new MockWeatherService { City = "Vienna" });

    [UiPreview("Offline", Profile = UiPreviewProfiles.Widget)]
    public static UiElement Offline() => WeatherView.Build(new MockWeatherService { Offline = true });

    [UiPreview("Long city name", Profile = UiPreviewProfiles.Widget)]
    public static UiElement LongName()
        => WeatherView.Build(new MockWeatherService { City = "Llanfairpwllgwyngyllgogerychwyrndrobwllllantysiliogogogoch" });
}

Developer Tools lists the three scenarios under WeatherView, renders each through the same renderer the app uses, and lets you resize the surface freely while it re-lays-out. Good candidates: disconnected, empty, mid-load, failing, and a translation three times longer than the English.

Writing a scenario

[UiPreview("Offline")]
public static UiElement Offline() => WeatherView.Build(new MockWeatherService { Offline = true });

The method must be static, take no parameters, and return a UiElement, a UiView or a UiPreview. Nothing is injected: a scenario builds its own mocks, and nothing reaches the real service.

Grouping and profile

[UiPreview("Long text", View = "WeatherDetailsView", Profile = UiPreviewProfiles.Config)]

Member	Default	Meaning
`Scenario` (constructor)	-	The scenario’s name. Required, not blank.
`View`	The declaring type’s name without a trailing `Previews` (`WeatherViewPreviews` becomes `WeatherView`)	The view the scenario groups under.
`Profile`	`UiPreviewProfiles.Config` (`config`)	The component namespace the tree is authored in: `config` or `widget`. It only sets up the canvas before the first tree arrives; the tree decides how it renders.

Releasing what a mock owns

[UiPreview("Live feed", Profile = UiPreviewProfiles.Widget)]
public static UiPreview LiveFeed()
{
    var feed = new MockWeatherFeed();

    return UiPreview.Of(WeatherView.Build(feed), feed);
}

Opening, switching, refreshing and closing a preview each end the previous session. Hand anything that must be stopped - a timer, a subscription, a fake connection - to UiPreview.Of as an IDisposable or IAsyncDisposable, and Macro Deck disposes it when the preview ends. A scenario that only builds a tree from plain data returns the element and never mentions UiPreview.

What a preview cannot affect

Fact	Consequence
Discovery reads metadata only.	A scenario runs only when someone opens it; declaring one costs a running host nothing.
A preview renders on its own `developer-preview` surface.	No provider you wrote for `config`, `widget`, `dialog` or `folder` is ever asked to serve one.
A malformed `[UiPreview]` method (not static, takes parameters, wrong return type) is skipped and reported in Developer Tools.	Discovery never fails, so one bad preview cannot take down your real surfaces.
A scenario that throws when opened fails only that preview.	Other previews and sessions carry on.
Listing and opening previews require an admin session.	Previews are not reachable by deck clients.

Over the plugin protocol

describe lists your scenarios in previews. MacroDeck.Plugin.Hosting scans the assemblies of your registered integrations plus the entry assembly, lazily. A developer-preview surface names one scenario by id in its attributes; the SDK builds that scenario ahead of every production path and never consults IUiProvider. See Serving a view.