How to get an Object Id on right click of a folder

Hi,

For context-menu,after right clicking on a folder I am not getting the object Id of a selected folder instead I am getting the parent folder's object Id.

Can anybody guide me on this I want an object Id of a selected folder not of a parent folder

In component.xml  

<param name="objectId" required="true" />

In java class:

objectId = args.get("objectId");

Thanks in advance