Moodle Plugins directory: Solution sheet | Moodle.org

Solution sheet
Assignment feedbacks ::: assignfeedback_solutionsheet
Maintained by
Henning Bostelmann
Allows teachers to upload files with solutions to their assignment, which can be released to students manually or at a scheduled time.
Latest release:
390 sites
114 downloads
36 fans
Current versions available: 5
In Mathematics and other science subjects, coursework assignments are
usually accompanied by model solutions which are released to students
after the due date, and to markers beforehand. This plugin allows
teachers to upload these solution sheets as files, e.g., in PDF format,
to the Moodle Assignment activity.
Solutions are initially hidden to students, and the teacher can release them either manually, or at a specified time after the due date. Futher, they can automatically be made unavailable after a configurable date.
Contributors
Henning Bostelmann (Lead maintainer)
Please login to view contributors details and/or to contact them
https://integration.moodle.org/job/Precheck%20remote%20branch/31769/artifact/work/smurf.html
However, teachers demand another option to NOT showing the solution sheet if the assignment has not been sent by the students. Our teachers understand "show to students: Yes" as showing it after doing the assignment. Currently, if the teacher configures "show to students: Yes", all students, even those that not even attempted to do the assignment, can view the solutions without restriction.
And, just a preference, Rather than in the header, Solution sheet access should be placed in the summary table ?
Can be placed there without using a column in the grading table ?
regarding your first point, that's an interesting suggestion. As you say, the plugin doesn't currently have feature to show solutions only to students who have attempted the assignment. I have for now noted this as CONTRIB-7029 and I might include this in a future version.
Regarding your second point, I'm afraid that the header is the only place where the subplugin structure allows me to display the solution sheet, without modifying the code of the core mod_assign module.
I'm running Moodle 3.4 with version 3.3.0 and I have problem with newly uploaded solution sheets. They are not displayed to my students and it throws this error:
Debug info:
Error code: filenotfound
Stack trace:
line 482 of /lib/setuplib.php: moodle_exception thrown
line 1881 of /lib/filelib.php: call to print_error()
line 4800 of /lib/filelib.php: call to send_file_not_found()
line 40 of /pluginfile.php: call to file_pluginfile()
The oldest assignments with solutions sheet are displayed correctly, so I do not know, where the problem is.
Michal
My system Moodle 3.7.2 (Build: 20190909)
I got this: [Error] Moodle required [2019052003]
Any help?