How to intercept double click event on a folder on osx?

Question

experts. what I want is like this: I create a folder named RootDir, then I double click the folder in Finder , I hope I can intercept the action and trigger specific action such as mounting this RootDir to another folder named MountDir and then open MountDir, not RootDir.

How should I do it (Using objective-c)? my platform is mountain lion (osx10.8) and I've tried using fsevent to monitor, but i don't think i can catch the action of folder open/close.... And is it the only way for me to use Finder injection to achieve this function? any suggestions would be appreciated.

Answer 1

You can associate AppleScript scripts with folders. Take a look at Folder Actions Reference

A Folder Action script is executed when the folder to which it is attached is opened or closed, moved or resized, or has items added or removed.