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codeBelt/addEventListenerRemoveEventListenerScopeFix

Last active December 20, 2015 12:29
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addEventListener and removeEventListener scope polyfill. Not fully tested in all browsers.
Raw
addEventListenerRemoveEventListenerScopeFix
<!DOCTYPE html>
<html>
<head>
<title></title>
<script src="polyfill.addEventListener.js"></script>
<script>
window.onload = function() {
(function() {
var Test = function() {
this.link = document.getElementById('js-link');
this.link.addEventListener('click', this.test, this, false);
this.image = document.getElementById('js-image');
this.image.addEventListener('click', this.test, this, false);
};
Test.prototype.test = function(event) {
event.preventDefault();
alert('click')
event.target.removeEventListener('click', this.test, this);
};
var test = new Test();
})();
}
</script>
</head>
<body>
<a href="javascript:void(0);" id="js-link">click</a>
<img id="js-image" width="100px" src="http://www.capca.ca/wp-content/uploads/Canada-small-87393222.jpg"/>
</body>
</html>
/**
* Polyfill for fix scoping and reference issues.
*/
//https://developer.mozilla.org/en-US/docs/Web/API/EventTarget.removeEventListener
(function(window, document)
{
// if (!Element.prototype.addEventListener) {
var oListeners = {};
function runListeners(event)
{
if (!event)
{
event = window.event;
}
for (var iLstId = 0, iElId = 0, oEvtListeners = oListeners[event.type]; iElId < oEvtListeners.elementList.length; iElId++)
{
if (oEvtListeners.elementList[iElId] === this)
{
for (iLstId; iLstId < oEvtListeners.elementCallbackList[iElId].length; iLstId++)
{
var obj = oEvtListeners.elementCallbackList[iElId][iLstId];
if (obj.e === this) {
obj.c.call(obj.s, event);
}
}
break;
}
}
}
Element.prototype.addEventListener = function(type, callback, scope, useCapture)
{
if (oListeners.hasOwnProperty(type))
{
var oEvtListeners = oListeners[type];
for (var nElIdx = -1, iElId = 0; iElId < oEvtListeners.elementList.length; iElId++)
{
if (oEvtListeners.elementList[iElId] === this)
{
nElIdx = iElId;
break;
}
}
if (nElIdx === -1)
{
oEvtListeners.elementList.push(this);
oEvtListeners.elementCallbackList.push([
{c: callback, s: scope, e: this}
]);
this["on" + type] = runListeners;
}
else
{
var aElListeners = oEvtListeners.elementCallbackList[nElIdx];
if (this["on" + type] !== runListeners)
{
aElListeners.splice(0);
this["on" + type] = runListeners;
}
for (var iLstId = 0; iLstId < aElListeners.length; iLstId++)
{
if (aElListeners[iLstId].c === callback && aElListeners[iLstId].s === scope && aElListeners[iLstId].e === this)
{
return;
}
}
aElListeners.push({c: callback, s: scope, e: this});
}
}
else
{
oListeners[type] = { elementList: [this], elementCallbackList: [
[
{c: callback, s: scope, e: this}
]
] };
this["on" + type] = runListeners;
}
};
Element.prototype.removeEventListener = function(type, callback, scope, useCapture)
{
if (!oListeners.hasOwnProperty(type))
{
return;
}
var oEvtListeners = oListeners[type];
for (var nElIdx = -1, iElId = 0; iElId < oEvtListeners.elementList.length; iElId++)
{
if (oEvtListeners.elementList[iElId] === this)
{
nElIdx = iElId;
break;
}
}
if (nElIdx === -1)
{
return;
}
for (var iLstId = 0, aElListeners = oEvtListeners.elementCallbackList[nElIdx]; iLstId < aElListeners.length; iLstId++)
{
if (aElListeners[iLstId].c === callback && aElListeners[iLstId].s === scope && aElListeners[iLstId].e === this)
{
aElListeners.splice(iLstId, 1);
}
}
};
// }
})(window, document);
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