Emit Events Using Symbols

class Example extends Phaser.Scene
{
    constructor ()
    {
        super();
    }

    preload ()
    {
        this.load.setBaseURL('https://cdn.phaserfiles.com/v410');
        this.load.image('girl', 'assets/pics/manga-girl.png');
        this.load.image('plush', 'assets/pics/profil-sad-plush.png');
    }

    create ()
    {
        //  Our ES6 Symbols we'll use for both the handler and event emitter
        const plushSymbol = Symbol();
        const girlSymbol = Symbol();

        //  This handler will only be called once, no matter how many times the event fires
        this.events.once(plushSymbol, this.addPlushHandler, this);
        this.events.once(girlSymbol, this.addGirlHandler, this);

        this.events.emit(girlSymbol);
        this.events.emit(girlSymbol);
        this.events.emit(girlSymbol);

        this.events.emit(plushSymbol);
        this.events.emit(plushSymbol);
        this.events.emit(plushSymbol);
    }

    addPlushHandler ()
    {
        let x = Phaser.Math.Between(100, 700);
        let y = Phaser.Math.Between(0, 300);

        this.add.image(x, y, 'plush');
    }

    addGirlHandler ()
    {
        let x = Phaser.Math.Between(100, 700);
        let y = Phaser.Math.Between(300, 600);

        this.add.image(x, y, 'girl');
    }

}

const config = {
    scale: { mode: Phaser.Scale.FIT },
    type: Phaser.AUTO,
    parent: 'game-container',
    width: 800,
    height: 600,
    scene: Example
};

let game = new Phaser.Game(config);