event emitter (dispatcher) for anuglar2 - depends on EventEmitter

dispatcher.ts

import {EventEmitter} from 'angular2/angular2';

class Dispatcher {
    subjects = {};

    constructor() {
    }

    emit(topic, data = null) {
        this.getInstance(topic).next(data);
    }

    on (topic, handler) {
        this.getInstance(topic).subscribe(handler);
    }

    off(topic) {
        if (this.subjects[topic]) {
            this.subjects[topic].dispose();
            delete this.subjects[topic];
        }
    }

    dispose() {
        var subjects = this.subjects;

        for (let prop in subjects) {
            if (subjects.hasOwnProperty(prop)) {
                subjects[prop].dispose();
            }
        }

        this.subjects = {};
    }

    private getInstance(topic) {
        return this.subjects[topic] || (this.subjects[topic] = new EventEmitter());
    }
}


export default new Dispatcher();