I can't figure out how to listen to focus, click, onKeyUp and other basic dom events in ckeditor. In the events summary there is only a few events regarding the lifecycle of ckeditor. And the "textArea" of ckeditor is an iframe, and it's html itself, so it is not clear on what dom node to listen.
It's not a big deal, just do the following, works for focus, blur, click etc.
var ckeditor = CKEDITOR.instances['textArea_id'];
ckeditor.on('focus', fnHandler, context, data, priority);
or a jQuery example :
$(document).ready(function () {
$('#YOUR_TEXTAREA_ID').ckeditor(ckeditor_config);
CKEDITOR.instances.YOUR_TEXTAREA_ID.on('blur', fnHandler);
});
I don't know when this support appeared, but it definitely works for 3.5.x