This is an original version, some what based on the gtk-2 one. Also using some code from a previous submission. This one has gone a different direction, so should not be considered as part of the other. There are two versions, this one, and the previous one submitted by Mike Blumenkrantz. Both versions can be seen in their own branches here.
The 2nd, "My branch/version" is the one being submitted for review and inclusion. I will support and be available to Gnupg project for long term maintenance, as needed. This is the initial submission for review, subject to code format modifications, code changes, UI changes, etc as needed to get it added to pinentry ASAP.
Please let me know what is needed, and I will modify and resubmit. Once approved I will provide a better commit message for actual code/commit inclusion. Thanks!