Compatibility - AttachEvent Vs AddEventListener Vs Other?
Mar 17, 2003
As I understand it so far:
element.attachEvent()
IE 5+ for PC
element.addEventListener()
Gecko, KHTML
element.event
NS3+, IE4+, dunno about opera or others
Since I'm only concerned with attaching a single event and don't care about bubbling/capturing, am I best off not using the old style of event registering to assure maxium compatibility?
Today I have been testing the event models from Netscape 4.8 and IE 4 to the current crop of browsers. I'd like to write a small event library similar in purpose to the Yahoo! UI event library but with less features and code. The Yahoo! event library is one of the best libraries in YUI but it still seems to me to have some confused code...that or I'm still confused.
The Yahoo! UI library focuses on using addEventListener and attachEvent. However, due to the click and dblclick bugs in Safari a long legacy event workaround is included to use a Netscape4-type event model for Safari. Something like this
var listeners = [function(event){}, function(event){}]; document.getElementById('blue').onmouseover = function(event) { for (var i=0; i<listeners.length; i++) { listeners[i](event); } };
With this above example, multiple handler functions can be fired for a single event. I imagine that this is an old trick that has been around for a long time, yes?
With all the new browsers I tested with this legacy workaround, the listener handlers can use event.stopPropogation() or event.cancelBubble=true and they work as desired. The handler functions can also use event.preventDefault() and event.returnValue=false and they too work. These seem to work because the event object passed to the handlers is a modern event object and not one from Netscape4.
My question is, if Safari needs this legacy workaround, and the legacy workaround seems to work in all the browsers that have addEventListener or attachEvent, then why bother with the addEventListener and attachEvent functions at all? Why not just use the legacy way for all browsers and all type of events.?
var img = document.createElement("img"); img.attachEvent("onclick",alert("test")); var div = document.createElement("div"); div.appendChild(img); //can't work; div.innerHTML="<-click this";
but i use attachEvent like this,it work; eg:
var img = document.createElement("img"); img.attachEvent("onclick",alert("test")); var text = document.createElement("span"); text.innerHTML="<-click this"; var div = documet.createElement("div");
div.appendChild(img); //can work div.appendChild(text);
I am trying to write a loop that will add 10 divs to the screen. Each div will have an onclick event. The function that will be called onclick requires a parameter. That parameter is dynamic based on the index of the loop. In Firefox this is no problem. However in IE I get some results that I wouldn't expect.
Here is my code:
for(var i = 0; i < 10; i++) { var linename = jsonObj.lines[i].line; var childcountid = jsonObj.lines[i].childcount; var lineid = jsonObj.lines[i].lineid;
var newdiv = document.createElement('div'); newdiv.setAttribute("id","main" + i); if (navigator.appName == "Microsoft Internet Explorer") { //************ this is the problem area ***************** newspan.attachEvent("onclick", function() {getCategories('main' + i)}); } else { newspan.setAttribute("onclick", "getCategories('main" + i + "')"); } document.getElementById('container').appendChild(n ewdiv); }
What happens is when the element is clicked the parameter being passed to getCategories is always 'main9' IE always grabs the current value of i, not the value of i at the stage of the loop that attachEvent was called.....
The event added to the flash object (videoPlayer) or to its container (player) responds as expected in all browsers except ie. I trtied everything I could possibly think of and still can't get it work in ie. The only event that works in ie is "onactivate".
I have a cross domain iframe resizing script (using postMessage) that works perfectly in Chrome, FF, Safari and IE9 - browsers that use addEventListener I'm trying to get it to work in IE8 by adding what I thought was the right language for attachEvent, but it's not working in IE8 - I just get 'Object doesn't support this property or method' - again just in IE8.
A page I'm working on lets users open a new window, which in turn lets them send data back to the parent page to create new table rows, cells, links, etc. One of the links created is "delete", so it should delete the row that the delete link belongs to when clicked on. I can do this no problem in ff using the setAttribute('onclick',onClickEvent), but can't do this in IE. I'll show some code to make this easier to understand....
This makes my life a bit easier. After executing this script you should be able to addEventListener on all elements instead of determining if you want to call attachEvent or addEventListener. Edit: This is the original version. The revised version is below if (!document.addEventListener && document.attachEvent) { Object.prototype.addEventListener = function(eventName, func, capture) { if (this.attachEvent) this.attachEvent('on' + eventName, func); }
var i, l = document.all.length;
for (i = 0; i < l; i++) document.all[i].addEventListener = Object.prototype.addEventListener;
This one is harder to use but it is nicer to the DOM and all newly created objects. The problem with it is that addEventListener will only be available after the page loads.
If you want to use addEventListener from a window.onload script make sure that this code is included in the body, not in the head. document.body.onload is called before window.onload.
Now, only elements that already have attachEvent will get an addEventListener. Elements created with document.createElement will automatically get addEventListener.
function createIEaddEventListeners() { if (document.addEventListener || !document.attachEvent) return;
function ieAddEventListener(eventName, handler, capture) { if (this.attachEvent) this.attachEvent('on' + eventName, handler); }
function attachToAll() { var i, l = document.all.length;
for (i = 0; i < l; i++) if (document.all[i].attachEvent) document.all[i].addEventListener = ieAddEventListener; }
var originalCreateElement = document.createElement;
document.createElement = function(tagName) { var element = originalCreateElement(tagName);
if (element.attachEvent) element.addEventListener = ieAddEventListener;
I was using this script to learn how to use event listeners and I need to know how to make it work for IE. I keep finding attachEvent scripts that look like they will work, but I get nothing. I've spent several hours finding script after script that simply don't work. I don't know where to turn next. Any script to attach these events to IE?
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "[URL]"> <html> <head> <title>Test</title> </head> <body><div> <script type="text/javascript">
if(!Array.prototype.link) Array.prototype.link = function(f) { for(var Obect1 = new Array(), i = 0, n = this.length, t = arguments[1]; i < n; i++) Obect1[i] = f.call(t, this[i], i, this);return Obect1;}; Array.prototype.linkMethod = function(m) { var n = this.length, args = this.slice.call(arguments, 1);if(typeof m == "string" && n > 0) m = this[0][m];for(var Obect2 = [], i = 0; i < n; i++) Obect2[i] = m.apply(this[i], args);return Obect2;}; .....
I'm trying to add a clickevent to an anchor that I created trough DOM. This his how the code looks:
var oSubLink = document.createElement("A"); oSubLink.appendChild(document.createTextNode("+")); oCel.appendChild(oSubLink); oSubLink.addEventListener("click", klapUit(oTabel.id, eigenschappen[2]), false);
It failes at the addEventListener call, saying "No such interface supported" (appears to be one of the two default error messages IE gives when it can't handle your JS :mad: ).
How can I fix this? The solution should work in IE6, FF, Opera, Mozilla and Safari.
Is there a way to send parameters to the function being added to an event with addEventListener. I.E. say you have this function
Code: function someFcn(i){ alert(i); } and I add it to an object.
Code: someElement.addEventListener('focus', someFcn, false); Is there a way to send a parameter to someFcn. For Example I have tried this but it failed
Code: var someString = 'Hello World' someElement.addEventListener('focus', someFcn(someString), false);
When you use addEventListener (or addEvent in IE) to call an object method, does it call it with the correct this parameter?
The ECMAScript reference has a lot to say about the caller using Function.prototype.call or Function.prototype.apply and passing the correct this pointer for the context, but how does addEventListener determine the correct this pointer. Or does it just punt and pass the global context, thus making it impossible to refer to the object this in an object method used as an event listener?
Task: I would like to implement a CtrlEnter event that would work on both IE and FF.
My approach: use addEventListener() and attachEvent() to capture the event then trigger a function to check for CtrlEnter: if (oTarea.addEventListener) { oTarea.addEventListener('keyup', function() {checkCtrlEnter(event);}, false); } else if (oTarea.attachEvent) { oTarea.attachEvent('onkeyup', function() {checkCtrlEnter(event);}); }
function checkCtrlEnter(e) { if (e.ctrlKey && e.keyCode == 13) { // do something } return false; }
I've been using window.onerror to capture and report JavaScript errors from other users for debugging an application I've written. But I've run into a strange issue with Firefox and window.onerror.
It seems that any code that executes, having originated from an "element.addEventListener", causing an error does not activate "window.onerror". But it does at least show up in Firefox's JavaScript error console. Internet Explorer doesn't appear to suffer from the same issue when it uses it's equivalent "element.attachEvent".
Does anyone know why this is and if there is any workarounds or if it's possibly a bug? Code:
I am trying to create a script that will cover cross-browser limitations in adding event listeners to elements. I have found plenty of resources to add a listener but can't find any way of assigning a function containing arguments. Here is what I have so far:
/* Attach events regardless of browser */
function addEvent(obj, evType, fn) { if (obj.addEventListener) { obj.addEventListener(evType, fn, false); return true; } else if (obj.attachEvent) { var r = obj.attachEvent("on"+evType, fn); return r; } else { return false; }}
/* Contains all attachments to be made on page load */
function load() { item = document.getElementById('toggleControl'); addEvent(item, 'click', toggle);
/* Add event to page load and assign load() function */
addEvent(window, 'load', load);
The actual functions for toggle and runAlert are in a seperate .js file, but are standard functions. the problem is that I can't find a way to perform the equivalent of:
I've created an object and within this object, I've added an eventlistener. But the problem now is that after addEventListener is being called to access a callback function, the callback function is not able to access the properties within its own class. Code: