Since we are pre-processing anyway the AppStream metadata file (because
appstream-glib doesn't pass unknown XML attributes, cf. a previous
commit), it does feel silly now to continue loading the file at runtime
too. Let's just pre-process more data into the constructed C files, i.e.
get the introduction paragraphs and the change items too.
The only other remaining advantage of appstream-glib was that it was
handling the localization but since we also have these localized strings
in our gettext files, we can as well translate with gettext as any other
strings and it works just fine.
It will also get rid of any packaging issue, forgetting to package the
metadata file (as we had on the Windows installer, and still have on the
macOS package). Now it will just always work because data is internal.
The idea is to add some "demo" attribute to a list item inside the
<release> tag, since we already decided that (for now at least) we'd
keep a strict "intro + list" logics, as we did until now.
This demo attribute uses an internal format to specify successive
widgets to blink (like a demo path towards a feature). For now, what it
allows is:
* raise the toolbox, select a tool and blink the tool button.
* raise a dockable, blink any widgets in there.
Now it is still limited and needs to evolve. In particular:
* What happens if the blinked tool button was explicitly removed from
Preferences? Should we re-add it for the demo? And once done, should
we remove it again? Then should we select back the tool previously
selected?
* What happens if the dockable widget is not visible? Should we allow
changing the settings to be able to demo correctly the new/changed
settings? Should it be temporary? If temporary, it can be annoying as
you'd still have to look attentively the demo to find back the path to
the new settings. If not temporary, some people may dislike we touch
their settings.
* What if docks are hidden? Should we unhide them, then hide them back
after demo time?
Also regarding the implementation: originally I wanted to just grab the
demo attribute directly from the AppStream metadata file, but I realized
that appstream-glib cleans out unknown attribute from the XML. I could
then simply parse the file with a generic XML parser, but I found
simpler to pre-parse it into a header built within GIMP. I still use
appstream-glib at runtime as it takes care of localization for us
(though in the same time, we also have the localization in the main po
files, so maybe we could just embed the release note strings as well).
See appstream-glib report: https://github.com/hughsie/appstream-glib/issues/431
Jehan