plugin: show a long list in the new project setup

Hi,

I'm working on a plugin and I added a new c++ project type.

When the user select this project type he has to select from a long list (can be more that 100 elements).

At now I add all this element into a JPanel with a BoxLayout and in this way the user has to use the standard scroll bar that appears to top-right side of the dialog box in order to scroll down and select the elements. 

I would like improve the user experience in two way: have a multi columns list and add the scroll bar to the panel showing the list, not to the dialog gran-parent. But I'm stuck because I can't get the real dimension of the parent dialog (for the multi columns option) and the jscrollpane doesn't work well I think for the same reason.

I saw that at the end of the parent chain there is a Component object that contains those information (I think it is dialog box parent) but using it it seems to me too risky; I suppose can be changed every version.

Somebody can help me ?

Regards,

Paolo