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Veams Vent Plugin (@veams/plugin-vent)

The Veams Vent Plugin is a global publish and subscribe object. You can use this plugin to communicate between modules independently.

Veams exposes a global event object (Veams.EVENTS) which can be used and extended by this plugin.

The module extends the default EVENTS object of Veams when you pass the option called furtherEvents.

TypeScript is supported.

---------------------

Installation

$3

`` bash
npm install @veams/plugin-vent --save
`

$3

` bash
yarn add @veams/plugin-vent
`

---------------------

Usage

` js
import Veams from '@veams/core';
import VentPlugin from '@veams/plugin-vent';
import EVENTS from './custom-events';

// Intialize core of Veams
Veams.onInitialize(() => {
// Add plugins to the Veams system
Veams.use(VentPlugin, {
furtherEvents: EVENTS
});
});
`

$3

| Option | Type | Default | Description |
|:--- |:---:|:---:|:--- |
| _furtherEvents_ | {Object} | [false] | Add your custom events to the global events object of Veams. |

$3

When enabled the Api provides a way to subscribe and unsubscribe from global events and publish to the subscribers.

#### Veams.Vent.subscribe(name:string, callback:function)

_alias: .on()_

* @param {String} name - Event name which you subscribed to.
* @param {Function} callback - The callback function which get executed when event is triggered.

#### Veams.Vent.unsubscribe(name:string, callback:function)

_alias: .off()_

* @param {String} name - Event name which you have subscribed to.
* @param {Function} callback - The callback function which is registered.

#### Veams.Vent.publish(name:string, obj?:object, scope?:any)

_alias: .trigger()_

* @param {String} name - Event name which you have subscribed to.
* @param {Object} obj - Optional custom data object which you can pass.
* @param {scope} any - Optional scope/context on which you want to execute .call().

---------------------

Example

$3

` js
// Let's add a throttle to the scroll event and trigger that
window.onscroll = Veams.helpers.throttle((e) => {
Veams.Vent.publish(Veams.EVENTS.scroll, e);
}, 200);

// Now we can easily catch that ...
Veams.Vent.subscribe(Veams.EVENTS.scroll, () => {
console.log('Throttled scroll captured ... ');
});
`

$3

` js
const dataHandler = (data) => {
// Make something with the data ...
console.log('my custom data received by publish(): ', data);
})

Veams.Vent.subscribe('custom:event', dataHandler);

Veams.Vent.subscribe(Veams.EVENTS.resize, () => {
// First we want to publish it, so that dataHandler() will be executed
Veams.Vent.publish('custom:event', {
testData: 'My test data'
});

// After that we unsubscribe to make sure that dataHandler() is only executed once
Veams.Vent.unsubscribe('custom:event', dataHandler);
});
``

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