Class AcApLayerStateCmd

Abstract base class for all CAD commands.

This class provides the foundation for implementing CAD commands with:

  • Command name management (global and localized names)
  • Lifecycle event handling (command start/end)
  • Execution framework with context access
  • Event notification system

Commands are the primary way users interact with the CAD system. Each command represents a specific operation like drawing lines, selecting objects, zooming, etc.

Command Lifecycle

  1. Command is triggered via trigger() method
  2. AcEditor.commandWillStart event is fired
  3. execute() method is called with current context
  4. AcEditor.commandEnded event is fired

Example

class MyDrawCommand extends AcEdCommand {
  constructor() {
    super();
    this.globalName = 'DRAW';
    this.localName = 'Draw Line';
  }

  execute(context: AcApContext) {
    // Implement command logic here
    const view = context.view;
    const document = context.doc;
    // ... drawing logic
  }
}

// Usage
const command = new MyDrawCommand();
command.events.commandWillStart.addEventListener(args => {
  console.log('Command starting:', args.command.globalName);
});
command.trigger(context);

Hierarchy (View Summary)

Constructors

constructor

Accessors

globalName localName mode userData

Methods

execute onCommandEnded onCommandWillStart trigger

Constructors

constructor

  • new AcApLayerStateCmd(): AcApLayerStateCmd

    Creates a new command instance.

    Initializes the command with empty names. Subclasses should set appropriate global and local names in their constructors.

    Returns AcApLayerStateCmd

Accessors

globalName

  • get globalName(): string

    Gets the global (untranslated) name of the command.

    The global name is typically used for programmatic access and should remain consistent across different language localizations.

    Returns string

    The global command name

  • set globalName(value: string): void

    Sets the global (untranslated) name of the command.

    Parameters

    • value: string

      The global command name (e.g., 'LINE', 'CIRCLE', 'ZOOM')

    Returns void

localName

  • get localName(): string

    Gets the local (translated) name of the command.

    The local name is displayed to users and should be localized to the current language/region.

    Returns string

    The localized command name

  • set localName(value: string): void

    Sets the local (translated) name of the command.

    Parameters

    • value: string

      The localized command name (e.g., 'Draw Line', 'Zoom In')

    Returns void

mode

  • get mode(): AcEdOpenMode

    Gets the minimum access mode required to execute this command.

    Commands with higher mode requirements can only be executed when the document is opened in a compatible mode. Higher value modes are compatible with lower value modes.

    Returns AcEdOpenMode

    The minimum access mode required

  • set mode(value: AcEdOpenMode): void

    Sets the minimum access mode required to execute this command.

    Parameters

    • value: AcEdOpenMode

      The minimum access mode (Read, Review, or Write)

    Returns void

userData

  • get userData(): TUserData

    Gets the custom user-defined data associated with this command.

    userData is a generic, strongly-typed container that allows consumers of the command to attach arbitrary metadata without modifying the command class itself.

    The shape of userData is defined by the generic parameter TUserData when the command is declared:

    Returns TUserData

    The user-defined data object associated with this command

    Example

    interface MyCommandData {
      sourceLayerId: string
      isPreview: boolean
    }

    class MyCommand extends AcEdCommand<MyCommandData> {}

    const cmd = new MyCommand()
    cmd.userData.sourceLayerId = 'Layer-01'
    cmd.userData.isPreview = true

    This design provides flexibility similar to THREE.Object3D.userData while preserving full compile-time type safety.

Methods

execute

  • execute(_context: AcApContext): Promise<void>

    Executes the command logic.

    This abstract method must be implemented by subclasses to define the specific behavior of the command. The method receives the current application context providing access to the view and document.

    Parameters

    Returns Promise<void>

    Example

    execute(context: AcApContext) {
      const view = context.view;
      const doc = context.doc;

      // Get user input
      const point = await view.editor.getPoint();

      // Create entity in document
      const entity = new SomeEntity(point);
      doc.database.addEntity(entity);
    }

ProtectedonCommandEnded

  • onCommandEnded(_context: AcApContext): void

    Called after the command has finished executing.

    This lifecycle hook is intended for cleanup or follow-up logic, such as:

    • Releasing resources
    • Resetting editor state
    • Finalizing transactions

    The default implementation does nothing.

    Parameters

    Returns void

ProtectedonCommandWillStart

  • onCommandWillStart(_context: AcApContext): void

    Called right before the command starts executing.

    This lifecycle hook is intended for subclasses that need to perform setup work before execute() runs, such as:

    • Initializing temporary state
    • Locking resources
    • Preparing UI or editor state

    The default implementation does nothing.

    Parameters

    Returns void

trigger

  • trigger(context: AcApContext): Promise<void>

    Triggers the command execution with proper event handling.

    This method should not be overridden by subclasses as it handles the event notification workflow. Subclasses should implement the execute() method instead.

    The execution flow:

    1. Fires commandWillStart event
    2. Calls the execute() method
    3. Fires commandEnded event

    Parameters

    • context: AcApContext

      The current application context containing view and document

    Returns Promise<void>

    Example

    const command = new MyCommand();
    command.trigger(docManager.context);

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