Disabling click event handlers

Question

I am trying to basically disable the click event on a <div> temporarily.

I have tried the following (preview):

$('hello').observe('click', function (e) {
    e.stop();
});

$('hello').observe('click', function (e) {
    alert('click not stopped!');
});

However, when #hello is clicked, the alert box still appears. I do not want the second attached handler to be called, and I do not want to change the second handler.

I will also accept a solution such as:

$('hello').observe('click', function (e) {
    alert('click not stopped!');
});

$('hello').disableEvent('click');

// Now, handler won't be called

$('hello').observe('click', function (e) {
    alert('click not stopped (2)!');
});

// New handler won't be called, either

$('hello').enableEvent('click');

// Now, handler will be called

I am using the Prototype.js framework. This doesn't seem to be a browser-specific issue.

Answer 1

As I said in comments to roosteronacid's answer, I wrote an extension to Event.observe. Works in most browsers, but not IE.

// XXX HACK XXX
(function () {
    var handlerCache = $A([ ]);

    function findHandler(either) {
        var pair = handlerCache.find(function (pair) {
            return $A(pair).member(either);
        });

        return pair && pair[0];
    }

    function addHandler(handler) {
        function newHandler(e) {
            if (!e.halted) {
                handler.apply(this, arguments);
            }
        }

        handlerCache.push([ handler, newHandler ]);

        return newHandler;
    }

    Event.observe = Event.observe.extended(function ($super, element, eventName, handler) {
        handler = findHandler(handler) || addHandler(handler);

        $super(element, eventName, handler);
    });

    Event.stopObserving = Event.stopObserving.extended(function ($super, element, eventName, handler) {
        handler = findHandler(handler) || handler;

        $super(element, eventName, handler);
    });

    Element.addMethods({
        observe: Event.observe
    });

    Event.prototype.halt = function () {
        this.halted = true;
    };
}());

Note: Function.prototype.extended is a custom function which puts the original Event.observe in as $super.