I believe Ext.js was using jQuery, but I\'m not sure. Does anyone know if there is full compatibility with jQuery and Ext.js?
ExtJS used to be built on top of other libraries. With version 2 they had their own but still offered the possibility to use other libs. But not anymore with version 3. ExtJS core code is very very mature, very efficient and VERY tidy. If you ask me, their code is written a lot better than jQuery's but that's subjective.
Anyway. If you intend to use ExtJS but would like to use other libs as well you can still do that. But if you think that you'd rather use jQuery with ExtJS I suggest you don't do that, because your code will have many hacks to overcome differences. I would rather use just ExtJS. You'll like it and probably won't want to switch back anymore.