In LXQt's file manager, pcmanfm-qt, which can also optionally manage the desktop, it is not possible to drag and drop a file from ark to any pcmanfm-qt window, a folder therein, or the desktop.
STEPS TO REPRODUCE
1. Open an archive in ark
2. Open a pcmanfm-qt window
3. Drag and drop file from the archive to the pcmanfm-qt window
4. Ensure pcmanfm-qt is in control of the desktop (has to be run with `pcmanfm-qt --desktop`
5. Drag and drop file from the archive to the desktop
Dragging and dropping fails. A general prohibition sign badge appears over the dragged icon when mousing over the areas managed by pcmanfm-qt.
Dragging and dropping succeeds as it does with other archivers such as:
Linux: Lubuntu 19.10 (development)
KDE Frameworks Version: 5.58.0
Qt Version: 5.12.2
LXQt Version: 0.14.1
pcmanfm-qt Version: 0.14.1
Please report this to the pcmanfm-qt developers. They need to call the ark dbus api, similar to what dolphin does: https://cgit.kde.org/dolphin.git/tree/src/views/draganddrophelper.cpp
I don't know how they handle the other archivers. Would be interesting to have a standard way to extract files, if possible.
I submitted a new issue:
but also asked if they have any suggestion on how to do this in a more standard way to share it upstream.
LXQt has their own archiver (or rather, will; it hasn't hit v1 yet) and they have a generalized methodology to DND to anywhere using pure Qt methods:
Might be a nice alternative to forcing every single app that wants to interact with ark to have to write code specific to it. I mean if every file manager is expected to do that, it seems a little silly, especially if all the other archivers had the same expectation.
And as it turns out, file-roller and engrampa use Freedesktop's Direct Save Protocol (XDS) which seems about as standard as it comes:
(In reply to Elvis Angelaccio from comment #1)
> Please report this to the pcmanfm-qt developers. They need to call the ark
> dbus api, similar to what dolphin does:
> I don't know how they handle the other archivers. Would be interesting to
> have a standard way to extract files, if possible.
The pcmanfm-qt report for the same problem has a link to this PR in lxqt-archiver https://github.com/lxqt/lxqt-archiver/pull/93 As I understand from what it says, they managed to find "a standard way to extract files".
(In reply to Walter Lapchynski from comment #4)
> And as it turns out, file-roller and engrampa use Freedesktop's Direct Save
> Protocol (XDS) which seems about as standard as it comes:
Interesting, this is something we could support, but of course someone needs to do the work (patches welcome).
*** Bug 425938 has been marked as a duplicate of this bug. ***
I recently looked into this and it's not that easy:
1. XDS is not trivial to implement with Qt's DnD API (since you need write access to DnD data)
2. XDS does not work on Wayland, presumably due to the same reason. See also https://gitlab.gnome.org/GNOME/file-roller/-/issues/4
A better solution might be to have Ark offer access to the archive via a virtual (fuse) filesystem. That way the receiving app would see a regular file and Ark would automatically decompress it on the fly
See e.g. https://github.com/bugnano/archivefs