service-utilities/lib/EventRadio.js

Utility Package for FIORI UI5

/**
 * @module EventRadio
 * @description Utility class for UI5 Event Bus
 * @author jpanti
 * @version 1.0.0
 * @created 2025-08-01
 * @lastModified 2025-08-01
 * @license ISC
 */

sap.ui.define(["sap/ui/core/EventBus"], (EventBus) => {
  "use strict";
  const eventBus = EventBus.getInstance();

  class EventRadio {
    // Initialization ===================================
    static defaultEventID = "default";
    #sChannelID;
    getChannelID = () => this.#sChannelID;
    constructor(sChannelId) {
      this.#sChannelID = sChannelId;
    }
    // ==================================================

    // Core Methods =====================================
    #transmit(sEventId = this.defaultEventID, oData = undefined) {
      eventBus.publish(this.#sChannelID, sEventId, oData);
    }
    #listen(
      sEventId = this.defaultEventID,
      callback = (oData) => {},
      oListener = undefined
    ) {
      const callbackWrapper = (_sChannelId, _sEventId, oData) =>
        callback(oData);
      eventBus.subscribe(
        this.#sChannelID,
        sEventId,
        callbackWrapper,
        oListener
      );
    }

    // doesn't support multiple watchers yet
    listenOnce(
      sEventId = this.defaultEventID,
      callback = (oData) => {},
      oListener = undefined
    ) {
      const callbackWrapper = (_sChannelId, _sEventId, oData) =>
        callback(oData);
      eventBus.subscribeOnce(
        this.#sChannelID,
        sEventId,
        callbackWrapper,
        oListener
      );
    }
    // ==================================================

    // sEventIds can be either an array of string or just string
    // Extension Methods ================================
    transmit(sEventIds = this.defaultEventID, oData = undefined) {
      if (Array.isArray(sEventIds))
        sEventIds.forEach((sEventId) => this.#transmit(sEventId, oData));
      else if (typeof sEventIds === "string") this.#transmit(sEventIds, oData);
      return this;
    }
    listen(
      sEventIds = this.defaultEventID,
      callback = (oData) => {},
      oListener = undefined
    ) {
      if (Array.isArray(sEventIds))
        sEventIds.forEach((sEventId) =>
          this.#listen(sEventId, callback, oListener)
        );
      else if (typeof sEventIds === "string")
        this.#listen(sEventIds, callback, oListener);

      return this;
    }
    // ==================================================
  }

  return EventRadio;
});