A considerable part of the new skinning layer of Substance is geared towards enabling writing Swing applications that have UI capabilities of this WPF application designed by frog studio (mentioned a few months ago on this blog):

The required changes have slowly sipped into releases 4.2 and 4.3 of Substance, but were limited due to maintaining as much backwards compatibility as possible. However, the old skinning / theming layer was not up to the challenge, especially considering its deficiencies in handling mixed light / dark skins. This layer has been completely rewritten in version 5.0 (currently under development) and it is now possible to use different skins for different top-level windows (such as frames and dialogs).

To specify a custom skin for the specific top-level window, use the SubstanceLookAndFeel.SKIN_PROPERTY client property and set it on the root pane of that window. To get the skin of the specific control (to provide custom painting that is consistent with how Substance paints core and third-party Swing components), use the SubstanceLookAndFeel.getCurrentSkin(Component) API.

Here is a screenshot that shows an application with twelve top-level frames, each using its own skin (click for the fullsize version):

Note that applications using a single global skin do not incur performance overhead. Applications that use per-window skins do not incur performance overhead as well, but the memory consumption will be higher due to a larger number of cached images.

You’re more than welcome to test the latest development drop of Substance 5 and report any bugs (visual or exceptions) to the project mailing lists, forums on in a private e-mail.