V3: Event System

[Frederico Caldeira Knabben]

The new event system must be coded, as defined in the ​Event Driven page in the ODE docs.

[Frederico Caldeira Knabben]

The implementation of it can be found at the event.js file (CKEDITOR.event) in the CKEDITOR prototype.

Performance is quite important here.

[Martin Kou]

The most critical piece of code here is CKEDITOR.event::fire(), as it is expected that it will be called a lot. I used the following code snippet to test its performance:

a = new CKEDITOR.event();
for(var i=0;i<100000;i++)
    a.fire('nosuchevent', '');

The previous prototype code created two closures called stopEvent and cancelEvent for each time fire() is called... which doesn't seem very efficient. I've moved the creation of the two closures out in [2349] to improve performance. I've got a nearly 3x improvement in performance with the new code according to Firebug's profiler with the above code snippet.

[Frederico Caldeira Knabben]

The changes on [2349] have broken the event system because you may have nested fire() calls. For example, event A could call a function that fires event B. If event B got canceled, event A was being canceled as well.

I've made a small improvement over those changes with [2350], still avoiding creating the functions for each call, but fixing the above issue.