Allow to create/delete problems after finalization
This merge request:
- enables the ability to create and delete problems after an exam is finalized
- adds some text explaining how to add problems
- stops incorrect caching of problem images
Fixes #253 (closed), #266 (closed) and #276 (closed).
There are still two things that need attention:
- After deleting a problem it deletes the corresponding solution and widget.
However, I'm not sure about deleting the feedback options. In
database.py
it states that:
feedback option -- can be shared by multiple problems.
Contradictory, the FeedbackOption
seems to have a single Problem
associated with it, thus it seems safe to just delete them. Which one of these is actually the case? If they are indeed shared between problems, does Pony 'garbage collect' unreferenced entities automatically?
- This is a nice opportunity to also fix #253 (closed). I think the first option works well. When there is no widget selected the problem name input could be replaced with a short sentence explaining you need to draw rectangles to add problems.
Edited by Hugo Kerstens