API reference

C# APIs use the Loom namespace. Import the Solid APIs and TypeScript types below from @loomgui/bridge. For a walkthrough, start with The bridge model.

Bridge declarations

Public value properties expose state. Assigning a property sends the updated value to the UI. Computed getters do not automatically notify when their inputs change; see Computed values.

UI startup and context

bootBridge

bootBridge(options: LoomBootOptions): Bridge

Creates the bridge at app startup, normally in UI/src/bridge.ts. Supply initial state and, for browser previews, mock action handlers. See the bootBridge reference for options, return behavior, environment selection, and an example.

BridgeProvider

<BridgeProvider value={bridge}>
  <App />
</BridgeProvider>

Requires a Bridge value, normally returned by bootBridge. Wrap the app so its components can use bridge context. The starter does this in index.tsx.

useBridge

useBridge(): Bridge

Call during component setup beneath BridgeProvider; it throws when the provider is missing. Returns the bridge object with its generated properties and methods. Read state in Solid’s reactive expressions, and request game changes through actions.

onEvent

onEvent<K extends keyof BridgeEvents>(
  name: K,
  handler: (data: BridgeEvents[K]) => void,
): void

Call during component setup beneath BridgeProvider. Payloads follow the generated event type. The subscription is removed when its Solid owner is disposed; no unsubscribe value is returned. Do not call at module scope or from a click callback. See Events.

Actions and events in C#

A [BridgeAction] method accepts supported DTO or scalar parameters and may return void, a value, Task, or Task<T>. The generated UI call always returns a Promise; an exception rejects it. See Actions.

Declare an event with public Event<DamageEvent> TookDamage { get; } = new(); and send it with TookDamage.Fire(payload). An event is not replayed after a reload. Store values the UI needs to recover in state.

Collections and value types

See State and collections and DTO rules for initialization and supported shapes.

UI image exports

Use <LoomImage source={bridge.icon} alt="Item" />. A null or temporarily unavailable source displays no image. Texture2D and Sprite are snapshots; RenderTexture stays live without reassignment. Image references are state-only, not action parameters, return values, or event payloads. See Unity image sources.

Built-in state

Every bridge includes read-only loom state. Do not supply it in initial. See Built-in Loom state for the field table.

NavigationProvider

Wrap the app once. It supplies the controller used by nested NavigationScope components and is disposed with its Solid owner. Its options configure the controller when the provider is created.

Timing defaults are deadZone: 0.55, releaseZone: 0.35, initialRepeatDelay: 350, and repeatInterval: 100. Delay and interval are in milliseconds; releaseZone must be lower than deadZone.

NavigationScope

Requires an ancestor NavigationProvider. Renders a div and accepts its ordinary HTML attributes and children.

Buttons, links, and form controls are discovered automatically when visible and enabled. Use stable element IDs for remembered focus. Directional attributes are data-loom-nav-up, data-loom-nav-right, data-loom-nav-down, and data-loom-nav-left; their values are an ID selector within the scope, auto, or none.

LOOM_NAVIGATION_EVENT is loomnavigation, a bubbling, cancelable event whose detail has command, source, and scope. Prevent its default to handle a command yourself. See Keyboard and gamepad navigation for bindings, focus behavior, and complete examples.

Keyboard mode in Unity

LoomRuntime.KeyboardMode = LoomKeyboardMode.Gameplay;   // default
LoomRuntime.KeyboardMode = LoomKeyboardMode.Navigation; // Tab / Shift+Tab traversal

Switch the game’s action map and visible screen alongside this property. Input forwarding does not consume Unity gameplay input; see Keyboard ownership.

Editor menus

All commands are under Tools > Loom.