final-events
Version:
Event Dispatcher with bubbling feature
307 lines (261 loc) • 8.68 kB
JavaScript
/*! final-events 2015-02-13 */
// From https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/keys
if (!Object.keys) {
Object.keys = (function () {
'use strict';
var hasOwnProperty = Object.prototype.hasOwnProperty,
hasDontEnumBug = !({toString: null}).propertyIsEnumerable('toString'),
dontEnums = [
'toString',
'toLocaleString',
'valueOf',
'hasOwnProperty',
'isPrototypeOf',
'propertyIsEnumerable',
'constructor'
],
dontEnumsLength = dontEnums.length;
return function (obj) {
if (typeof obj !== 'object' && (typeof obj !== 'function' || obj === null)) {
throw new TypeError('Object.keys called on non-object');
}
var result = [], prop, i;
for (prop in obj) {
if (hasOwnProperty.call(obj, prop)) {
result.push(prop);
}
}
if (hasDontEnumBug) {
for (i = 0; i < dontEnumsLength; i++) {
if (hasOwnProperty.call(obj, dontEnums[i])) {
result.push(dontEnums[i]);
}
}
}
return result;
};
}());
}
// From https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/forEach
// Production steps of ECMA-262, Edition 5, 15.4.4.18
// Reference: http://es5.github.com/#x15.4.4.18
if (!Array.prototype.forEach) {
Array.prototype.forEach = function forEach(callback, thisArg) {
'use strict';
var T, k;
if (this == null) {
throw new TypeError("this is null or not defined");
}
var kValue,
// 1. Let O be the result of calling ToObject passing the |this| value as the argument.
O = Object(this),
// 2. Let lenValue be the result of calling the Get internal method of O with the argument "length".
// 3. Let len be ToUint32(lenValue).
len = O.length >>> 0; // Hack to convert O.length to a UInt32
// 4. If IsCallable(callback) is false, throw a TypeError exception.
// See: http://es5.github.com/#x9.11
if ({}.toString.call(callback) !== "[object Function]") {
throw new TypeError(callback + " is not a function");
}
// 5. If thisArg was supplied, let T be thisArg; else let T be undefined.
if (arguments.length >= 2) {
T = thisArg;
}
// 6. Let k be 0
k = 0;
// 7. Repeat, while k < len
while (k < len) {
// a. Let Pk be ToString(k).
// This is implicit for LHS operands of the in operator
// b. Let kPresent be the result of calling the HasProperty internal method of O with argument Pk.
// This step can be combined with c
// c. If kPresent is true, then
if (k in O) {
// i. Let kValue be the result of calling the Get internal method of O with argument Pk.
kValue = O[k];
// ii. Call the Call internal method of callback with T as the this value and
// argument list containing kValue, k, and O.
callback.call(T, kValue, k, O);
}
// d. Increase k by 1.
k++;
}
// 8. return undefined
};
}
//Allows only usage of `value` descriptor!
if (!Object.defineProperty) {
Object.defineProperty = function (obj, key, descriptor) {
obj[key] = descriptor.value;
}
}
if (!Object.defineProperties) {
Object.defineProperties = function (obj, descriptor) {
Object.keys(descriptor).forEach(function (key) {
Object.defineProperty(obj, key, descriptor[key]);
});
}
}
if (typeof window !== 'undefined') {
window.finalEvents = {};
}
(function (exports) {
function getDefaultDescriptor() {
return {
'@propagationStopped': {
writable: true,
value: false
},
stopPropagation: {
value: function () {
this['@propagationStopped'] = true;
}
}
};
}
exports.event = function (target) {
if (typeof target === 'string') {
target = {type: target};
}
if (!target['@propagationStopped']) { //the most characteristic property
Object.defineProperties(target, getDefaultDescriptor());
}
return target;
};
})(typeof exports === 'undefined' ? this['finalEvents'] : exports);
(function (exports) {
if (typeof finalEvents === 'undefined') { //node environment
exports.event = require('./event.js').event;
}
function initHandlersForEventType(eventType, target) {
if (!target.hasEventListener(eventType)) {
target['@eventListeners'][eventType] = [];
}
}
function addEventListener(eventType, eventHandler, useCapture) {
if (!(eventHandler instanceof Function)) {
throw new TypeError('eventHandler is not a function');
}
initHandlersForEventType(eventType, this);
this['@eventListeners'][eventType].push({
handler: eventHandler,
useCapture: useCapture,
once: false
});
return this;
}
function addOnceEventListener(eventType, eventHandler, useCapture) {
initHandlersForEventType(eventType, this);
this['@eventListeners'][eventType].push({
handler: eventHandler,
useCapture: useCapture,
once: true
});
return this;
}
function indexOfEventHandler(eventType, eventHandler, target) {
var eventListeners = target['@eventListeners'][eventType];
if (!eventListeners) {
return -1;
}
for (var i = 0; i < eventListeners.length; i += 1) {
if (eventListeners[i].handler === eventHandler) {
return i;
}
}
return -1;
}
function removeEventListener(eventType, eventHandler) {
var eventListeners = this['@eventListeners'][eventType];
var index = indexOfEventHandler(eventType, eventHandler, this);
if (index !== -1) {
eventListeners.splice(index, 1);
}
return this;
}
function removeEventListeners(eventType) {
this['@eventListeners'][eventType] = [];
return this;
}
function hasEventListener(eventType) {
return this['@eventListeners'][eventType] !== undefined && this['@eventListeners'][eventType].length > 0;
}
function callListeners(event) {
if (event.currentTarget.hasEventListener(event.type)) {
event.currentTarget['@eventListeners'][event.type].forEach(function forEachEventListener(listener) {
if (listener.useCapture && event.phase !== exports.CAPTURE_PHASE) {
return;
}
if (!listener.useCapture && event.phase === exports.CAPTURE_PHASE) {
return;
}
listener.handler.call(event.currentTarget, event);
if (listener.once) {
event.currentTarget.removeEventListener(event.type, listener.handler);
}
});
}
}
function findParents(target) {
var parents = [];
while (target = target.parent) {
parents.push(target);
}
return parents;
}
function capturePhase(event) {
var parents = findParents(event.target);
event.phase = exports.CAPTURE_PHASE;
while (!event['@propagationStopped'] && parents.length > 0) {
event.currentTarget = parents.pop();
callListeners(event);
}
}
function targetPhase(event) {
if (!event['@propagationStopped']) {
event.phase = exports.TARGET_PHASE;
event.currentTarget = event.target;
callListeners(event);
}
}
function bubblingPhase(event) {
event.phase = exports.BUBBLING_PHASE;
while (!event['@propagationStopped'] && event.currentTarget.parent) {
event.currentTarget = event.currentTarget.parent;
callListeners(event);
}
}
function dispatchEvent(event) {
event = exports.event(event);
event.target = this;
capturePhase(event);
targetPhase(event);
bubblingPhase(event);
return this;
}
function getDefaultDescriptor() {
return {
'@eventListeners': {value: {}},
addEventListener: {value: addEventListener},
on: {value: addEventListener},
once: {value: addOnceEventListener},
removeEventListener: {value: removeEventListener},
off: {value: removeEventListener},
removeEventListeners: {value: removeEventListeners},
hasEventListener: {value: hasEventListener},
dispatchEvent: {value: dispatchEvent},
trigger: {value: dispatchEvent},
emit: {value: dispatchEvent},
fire: {value: dispatchEvent}
};
}
exports.dispatcher = function (target) {
if (!target['@eventListeners']) { //the most characteristic property
Object.defineProperties(target, getDefaultDescriptor());
}
return target;
};
exports.CAPTURE_PHASE = 1;
exports.TARGET_PHASE = 2;
exports.BUBBLING_PHASE = 3;
})(typeof exports === 'undefined' ? this['finalEvents'] : exports);