Ephemeral Event Emitter

Examples
1

A Scene Plugin that emits events and clears listeners when the Scene shuts down.

Plugin

const EventEmitter = Phaser.Events.EventEmitter;
const ScenePlugin = Phaser.Plugins.ScenePlugin;

/**
 * @classdesc
 * EphemeralEventEmitter is a Scene Plugin that emits events.
 * Its listeners are automatically cleared when its Scene shuts down.
 *
 * @class EphemeralEventEmitter
 * @extends Phaser.Events.EventEmitter
 *
 * @param {Phaser.Scene} scene - The Scene that has installed this plugin.
 * @param {Phaser.Plugins.PluginManager} pluginManager - The Plugin Manager.
 * @param {string} pluginKey - The key under which this plugin has been installed into the Scene Systems.
 */
class EphemeralEventEmitter extends EventEmitter {
    constructor(scene, pluginManager, pluginKey) {
        super();
        ScenePlugin.call(this, scene, pluginManager, pluginKey);
    }

    /**
     * Called when the Scene boots.
     */
    boot() {
        this.systems.events.on('shutdown', this.shutdown, this);
        this.systems.events.on('destroy', this.destroy, this);
    }

    /**
     * Destroys this plugin, removing all listeners and releasing all references.
     */
    destroy() {
        this.shutdown();
        this.systems.events.off('shutdown', this.shutdown, this);
        ScenePlugin.prototype.destroy.call(this);
    }
}

Game configuration

new Phaser.Game({
    plugins: {
        // You can use any `mapping`.
        scene: [{ key: 'EphemeralEventEmitter', plugin: EphemeralEventEmitter, mapping: 'ee' }]
    }
});

Use in a scene

// These event handlers won't stack up after a restart.
this.ee.on('create', this.addNeuromancer, this);
this.ee.on('create', this.incCount, this);

this.ee.emit('create');
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