Enabling ExtJS code completion with IntelliJ IDEA

How do I enable auto-complete/code completion feature of IntelliJ IDEA to work with ExtJS javascript libr开发者_StackOverflow社区ary?

Thanks

This could probably be closed as a dup of this question:

Add ExtJS code assist to IntellijIDEA

The answer is here:

http://blogs.jetbrains.com/webide/2010/11/working-with-javascript-libraries-in-phpstorm-webstorm/

do you have the extjs javascript files in your project? I find that when I do Intellij is somewhat good at getting methods, but it doesn't always get all the available methods. I thinks its just a gotcha of dynamic languages -- an IDE can't know all the methods available because some are available only at runtime...