Adding multiple onload handlers

Question

I have two js files, each one with its own window.onload handler. Depending on how I attach the two onload handlers to the window object I get a different behaviour on the s

Answer 1

Thanks for the answers!

I rewrote my script2.js using addEventListener and attachEvent like this:

//addOnloadHandler(initAll1); // it works only when uncommenting this
addOnloadHandler(initAll2);

function initAll2() {
    alert("initAll2");
    if (linkHasOnclickHandler(document.getElementById("redirect"))) {
        alert("correct!"); 
    }
    else {
        alert("wrong!");
    }
}

function addOnloadHandler(newFunction) {    
    if (window.addEventListener) { // W3C standard
        window.addEventListener('load', newFunction, false); // NB **not** 'onload'
    }    
    else if (window.attachEvent) { // Microsoft
        window.attachEvent('onload', newFunction);
    }
}

function linkHasOnclickHandler(element) {
    var oldevent = document.getElementById("redirect").onclick;
    if (typeof oldevent == "function") {
        return true;
    }
    else {
        return false;
    }
}

As you can see, addOnloadHandler() has been rewritten using the native implementations you guys mentioned. I left script1.js untouched.

The resulting code still does not work (i.e., the "wrong!" alert message is shown). It only works when I register the onload initAll1() handler twice by uncommenting the first line of code in script2.js.

Apparently, mixing

window.onload = handler1;

and

window.addEventListener('load', handler2, false);

or

window.attachEvent('onload', handler2);

does not work fine.

Is there any way to work around this problem that does not imply touching script1.js?

Just in case you wonder why I don't want to touch script1.js, the reason is that I want my code (script2.js) to be reusable in other projects as well, no matter which other js files each project uses. So, it should work with every possible event-handling registration method used in script1.js.

thanks once more for your help!