There seems to be an issue with the prototype event registry after the 1.7.3 update, I was using prototype_event_registry on the element storage to access click events so that i could replay them.
This is so that I can stop events and optionally resume them based on a callback, everything was working fine, but after looking at the diffs for 1.7.0 and 1.7.3 it seems to be removed?
I know that this was internals and I probably shouldn't have used it in the first place. Anyway, down to my question:
I have updated my code to work with 1.7.3 but it seems extremely hacky to me, is there a better way of doing this?
/**
* creates a toggling handler for click events taking previous click events into account.
*
* w.r.t stopping of a click event, handles cases where the button is a submit or a normal button.
* in the case of a submit, calling <tt>Event.stop()</tt> should be sufficient as there are no other listeners on the button.
* however, if a normal button has a handler that calls <tt>save()</tt>, and another handler using client code and calling stop,
* it will not affect stopping of the event, since <tt>Event.stop</tt> only stops propagation, not other handlers!
*
* note that this function will always execute the specified handler before any other defined events.
*
* @param {Element} element the element to use for this click event
* @param {Function} handler the handler to use for this stopping click event, if this handler returns true,
* all other actions for the click event will be prevented
* @returns {Element} the element that was supplied as argument
*/
function stoppingClickEvent(element, handler) {
if (!element) throw 'cannot use method, if element is undefined';
// assign default handler if none was supplied
handler = handler || Prototype.emptyFunction;
if (element.type && element.type === 'submit') {
element.on('click', function(submitEvent) {
// call the supplied handler with the current element as context and the event as argument
// if it returns true, we should stop the event
var stopEvent = handler.call(element, submitEvent);
if (stopEvent) {
// since the element's default action will be to submit a form, we prevent it
submitEvent.stop();
}
});
} else {
// prototype 1.7.3 removed support for 'prototype_event_registry', so we need to do multiple hacks here
// first get the window of the element so we can access the prototype
// event cache from the correct context (frames)
var elementDoc = element.ownerDocument;
var elementWindow = elementDoc.defaultView || elementDoc.parentWindow;
if (!elementWindow) {
throw 'cannot access the window object for element ' + element.id;
}
// we are dealing with a normal element's click event, so we don't know how many click events have been set up.
// capture them all so we can decide to call them or not.
// FIXME: need a better way of doing this
var registry = elementWindow['Event'].cache[element._prototypeUID || element.uniqueID] || {},
events = registry['click'] || [];
// now that we have a copy of the events, we can stop them all and add our new handler
element.stopObserving('click').on('click', function(clickEvent) {
// call the supplied handler with the current element as context and the event as argument
// if it returns true, we should stop the event
var stopEvent = handler.call(element, clickEvent);
if (!stopEvent) {
// the event should not be stopped, run all the original click events
events.each(function(wrapper) {
wrapper.handler.call(element, clickEvent);
});
}
});
}
return element;
}
After running with the above code for 3-4 months, I finally decided to revert it. There seems to be a lot of issues, especially when dealing with multiple frames and event handlers on a single page.
The most prevalent one being, Event.cache for a specific element being undefined.
This may be due to incorrect handling above, but I highly suspect the new Event framework to be incorrect somehow, since a revert to 1.7.0 completely fixes all the issues I experienced.
Just for reference, this is the code I'm now using with 1.7.0:
/**
* creates a toggling handler for click events taking previous click events into account.
*
* w.r.t stopping of a click event, handles cases where the button is a submit or a normal button.
* in the case of a submit, calling <tt>Event.stop()</tt> should be sufficient as there are no other listeners on the button.
* however, if a normal button has a handler that calls <tt>save()</tt>, and another handler using client code and calling stop,
* it will not affect stopping of the event, since <tt>Event.stop</tt> only stops propagation, not other handlers!
*
* note that this function will always execute the specified handler before any other defined events.
*
* @param {Element} element the element to use for this click event
* @param {Function} handler the handler to use for this stopping click event, if this handler returns true,
* all other actions for the click event will be prevented
* @returns {Element} the element that was supplied as argument
*/
function stoppingClickEvent(element, handler) {
if (!element) throw 'cannot use method, if element is undefined';
// assign default handler if none was supplied
handler = handler || Prototype.emptyFunction;
if (element.type && element.type === 'submit') {
element.on('click', function(submitEvent) {
// call the supplied handler with the current element as context and the event as argument
// if it returns true, we should stop the event
var stopEvent = handler.call(element, submitEvent);
if (stopEvent) {
// since the element's default action will be to submit a form, we prevent it
submitEvent.stop();
}
});
} else {
// we are dealing with a normal element's click event, so we don't know how many click events have been set up.
// capture them all so we can decide to call them or not.
var registry = element.getStorage().get('prototype_event_registry') || $H(),
events = registry.get('click') || [];
// now that we have a copy of the events, we can stop them all and add our new handler
element.stopObserving('click').on('click', function(clickEvent) {
// call the supplied handler with the current element as context and the event as argument
// if it returns true, we should stop the event
var stopEvent = handler.call(element, clickEvent);
if (!stopEvent) {
// the event should not be stopped, run all the original click events
events.each(function(func) {
func.call(element, clickEvent);
});
}
});
}
return element;
}