Distinguish between local and non-local files with thumbnails

[tsujan]

libfm-qt has an option to make thumbnails only for local files but that option has no effect for now (pcmanfm-qt inherits it in its Preferences dialog).

[stefonarch]

It works here with samba, showing or not thumbnails on the other PC following setting in PCMan, maybe I miss something.

[tsujan]

@stefonarch, the code does absolutely nothing.

[tsujan]

Here, the problem is distinguishing between local and remote files. A native file may be remote (like a file in Google drive, mounted locally by rclone) and a non-native file can be local (like trash:///).

I tested by adding GLib's G_FILE_ATTRIBUTE_FILESYSTEM_REMOTE to libfm-qt (in 2 ways). It worked with trash (= local), smb (= remote) and sftp (= remote) but not with Google drive (should be remote but is considered local) and, probably, similar cases.

There's another GLib's attribute G_FILE_ATTRIBUTE_FILESYSTEM_USE_PREVIEW but it's mysterious to me and I didn't find it in the codes of well-known GTK file managers.

[tsujan]

I think the safest way of giving sense to that option is tolerantly considering "local" as "native". There is a good reason: most external thumbnailers — if not all — only work with native paths and, for example, can't make thumbnails inside trash:/// or recent:/// (while the built-in thumbnailer can). In this way, we'll have a more self-consistent thumbnail handling.

EDIT: Tested it but didn't like it. The above-mentioned reason seems good but, for example, having thumbnails with google drive isn't good.

[tsujan]

After 3 years, I didn't find a way better than using what GLib proposed, namely, G_FILE_ATTRIBUTE_FILESYSTEM_REMOTE: #1004. It might be useful later, with other operations that we don't want to do with remote files (nothing for now).

[stefonarch]

I tested with ftp, looks working. Indeed toggling the option doesn't change anything.

[tsujan]

toggling the option doesn't change anything.

It isn't supposed to reload anything (if you mean that). Either the view should be reloaded or the directory should be changed after toggling the option.

[stefonarch]

I meant remote thumbnails were always generated, with or without setting a hook at that option.

[tsujan]

Oh, you mean before the patch. Yes, remote internal thumbnails were always made.

[tsujan]

My approach failed (→ #1004 (comment)).

Since most parts of libfm-qt's code are optimized by using asynchronous info queries, a synchronous querying of filesystem info is a bad idea, while enabling of the setting about local-only thumbnails doesn't seem achievable asynchronously.