dom-delegator/index.js

Decorate elements with delegated events

var Individual = require("individual")
var cuid = require("cuid")
var globalDocument = require("global/document")

var DOMDelegator = require("./dom-delegator.js")

var versionKey = "13"
var cacheKey = "__DOM_DELEGATOR_CACHE@" + versionKey
var cacheTokenKey = "__DOM_DELEGATOR_CACHE_TOKEN@" + versionKey
var delegatorCache = Individual(cacheKey, {
    delegators: {}
})
var commonEvents = [
    "blur", "change", "click",  "contextmenu", "dblclick",
    "error","focus", "focusin", "focusout", "input", "keydown",
    "keypress", "keyup", "load", "mousedown", "mouseup",
    "resize", "select", "submit", "touchcancel",
    "touchend", "touchstart", "unload"
]

/*  Delegator is a thin wrapper around a singleton `DOMDelegator`
        instance.

    Only one DOMDelegator should exist because we do not want
        duplicate event listeners bound to the DOM.

    `Delegator` will also `listenTo()` all events unless
        every caller opts out of it
*/
module.exports = Delegator

function Delegator(opts) {
    opts = opts || {}
    var document = opts.document || globalDocument

    var cacheKey = document[cacheTokenKey]

    if (!cacheKey) {
        cacheKey =
            document[cacheTokenKey] = cuid()
    }

    var delegator = delegatorCache.delegators[cacheKey]

    if (!delegator) {
        delegator = delegatorCache.delegators[cacheKey] =
            new DOMDelegator(document)
    }

    if (opts.defaultEvents !== false) {
        for (var i = 0; i < commonEvents.length; i++) {
            delegator.listenTo(commonEvents[i])
        }
    }

    return delegator
}

Delegator.allocateHandle = DOMDelegator.allocateHandle;
Delegator.transformHandle = DOMDelegator.transformHandle;