Use "fast" content type as fallback if normal content type is unavailable

Closes #312

See merge request !161

It turns out that, depending on the responsible GVfs implementation,
a GFileInfo may not actually set the content type attribute even if
requested. Since knowing the content type is rather critical for eog
try to use the fast content type as a fallback in those cases.

The fast content type should be hardly unknown as it is usually just
based on the file extension.

Fixes #312.

This prefers the real content type, but automatically falls back to the
fast content type the other one isn't set in the GFileInfo.

Cheng-Chia Tseng authored Feb 11, 2024 and Administrator committed Feb 11, 2024

(cherry picked from commit cc4e8baf)

appdata: Remove none OARS tags

See merge request !159

"The old generator also included all the none-value entries—it
no longer does this, you can safely remove them.

If it only consists of none values, it’s safe to shorten it to just:
`<content_rating type="oars-1.1" />`"

More information: https://docs.flathub.org/docs/for-app-authors/appdata-guidelines/#oars-information

data: Update appdata

See merge request !158

- Update the donation URL.
- Add the cvs-browser and translate URLs.
- Add launchable tag.

These URLs are visible on Flathub and GNOME Software.

For more information: https://www.freedesktop.org/software/appstream/docs/chap-Metadata.html#tag-url"

This causes new images to be already at the correct position when the
"row-inserted" signal is emitted.

That should make the image index shown in the statusbar to be correct
when adding images in the middle. Previously the current image's index
would've been initially incorrect as it would count while the new image
was still at the end of the list.

Fixes #300.