a2ui_core library

Core A2UI protocol implementation for Dart.

Classes

A2uiClientAction
Reports a user-initiated action from a component.
A2uiClientError
Reports a client-side error.
A2uiMessage
Base class for all A2UI messages.
Action
Triggers a server-side event or a local client-side function.
BehaviorNode
CancellationSignal
A signal that can be used to cancel an operation.
CapitalizeFunction
Catalog<T extends ComponentApi>
A collection of available components and functions.
ChildListTemplate
A template for generating a dynamic list of children.
ChildNode
CommonSchemas
ComponentApi
A definition of a UI component's API.
ComponentContext
Context provided to components during rendering.
ComponentModel
Represents the state model for an individual UI component.
Computed<T>
Create a new signal that is computed based on the values of other signals.
CreateSurfaceMessage
Signals the client to create a new surface.
DataBinding
A JSON Pointer path to a value in the data model.
DataContext
Provides data access relative to a specific path in the DataModel.
DataModel
A standalone, observable data store representing the client-side state. It handles JSON Pointer path resolution and reactive signal management.
DataPath
A class for handling JSON Pointer (RFC 6901) paths.
DeleteSurfaceMessage
Signals the client to delete a surface.
Effect
Create an effect to run arbitrary code in response to signal changes.
EventListenable<T>
Read-only interface for subscribing to discrete events.
EventNotifier<T>
A synchronous, typed event emitter for discrete events.
ExpressionParser
A parser for A2UI expressions, supporting string interpolation and function calls.
FormatStringFunction
FunctionApi
A definition of a UI function's API.
FunctionCall
Invokes a named function on the client.
FunctionImplementation
A function implementation that can be registered with a catalog.
GenericBinder
Takes a component's raw JSON properties (which may contain data bindings, function calls, and action definitions) and resolves them into concrete values (strings, callbacks, child lists, etc). The resolved output updates automatically when underlying data changes.
MessageProcessor<T extends ComponentApi>
The central processor for A2UI messages.
MinimalButtonApi
MinimalCatalog
MinimalColumnApi
MinimalRowApi
MinimalTextApi
MinimalTextFieldApi
ReadonlySignal<T>
An interface for read-only signals.
Signal<T>
Instance of a new plain signal
SurfaceComponentsModel
Manages the collection of components for a specific surface.
SurfaceGroupModel<T extends ComponentApi>
The root state model for the A2UI system.
SurfaceModel<T extends ComponentApi>
The state model for a single UI surface.
UpdateComponentsMessage
Updates a surface with a new set of components.
UpdateDataModelMessage
Updates the data model for an existing surface.

Enums

A2uiReturnType
The type of value a function returns.
Behavior
Represents the intended runtime behavior of a property parsed from its schema.

Constants

maxAutoVivifyIndex → const int
The maximum list index that auto-vivification will expand to.

Functions

batch<T>(T fn()) → T
Combine multiple value updates into one "commit" at the end of the provided callback.
computed<T>(T fn()) → ReadonlySignal<T>
Create a new signal that is computed based on the values of other signals.
effect(dynamic fn()) → void Function()
Create an effect to run arbitrary code in response to signal changes.
signal<T>(T value) → Signal<T>
Create a new plain signal

Typedefs

FunctionInvoker = Object? Function(String name, Map<String, dynamic> args, DataContext context)
A function that invokes a catalog function by name.

Exceptions / Errors

A2uiDataError
Thrown during DataModel mutations (invalid paths, type mismatches).
A2uiError
Base class for all A2UI specific errors.
A2uiExpressionError
Thrown during string interpolation and function evaluation.
A2uiStateError
Thrown for structural issues in the UI tree (missing surfaces, duplicate components).
A2uiValidationError
Thrown when JSON validation fails or schemas are mismatched.
CancellationException
An exception thrown when an operation is cancelled.