[Shotwell] Problem importing iphone photos

[Julien Cubizolles <j cubizolles free fr>]

I've run into some trouble importing photos from Apple products (Iphone
and Ipad). They are missing some exif data, including the date. Somehow
they were imported in the right folder (I'm using a year/month/day
hierarchy) but are not associated with any event and so can't be browsed
easily.

I've all tagged them as "Iphone" during import (thanks to shotwell for
the "Last Import" feature) so I can easily select them.

I'm wondering what is the best course of action to add the correct exif
data, and get them to be associated with date events. I could play with
the exiv2 tool, and try to add the correct tag from the directory the
photo is stored. But by any chance, is there a way to do it from
shotwell, some "fix date exif" tool, followed by some reimport to
associate them with the right events ?

Thanks for your input.