Opening GtkDialog from gnome-shell

[segfault <segfault riseup net>]

Hi,

we are currently working on integrating support to unlock
TrueCrypt/VeraCrypt volumes in GNOME. The patches for libblockdev,
udisks, and GNOME Disks are already prepared. The next step is to
support unlocking TC/VC volumes via the GVfs udisks2 monitor, which uses
gnome-shell's ShellMountPasswordDialog.

We need to add multiple widgets (or what is called widgets in GTK) to
this dialog, because TC/VC volumes take a lot of different parameters,
to specify whether to open a hidden volume, use keyfiles, etc. The
design of the resulting dialog can be seen here [1] - we also tested the
design with users [2], and started discussing it on the gtk-devel list [3].

In this design, to allow the user to specify keyfiles, there should a
button in the ShellMountPasswordDialog, which opens a file chooser
dialog when clicked. Unfortunately, I couldn't find any code in GNOME
Shell which uses a file chooser dialog, and I wasn't able to open a
GtkFileChooserDialog (or any other GtkWindow) in gnome-shell without
causing gnome-shell to crash. So I would like to know: Is there a way to
achieve this without implementing a file chooser dialog from scratch? Or
do you have any other idea how we could solve this?

Cheers


[1]
https://labs.riseup.net/code/attachments/download/1843/gvfs-monitor-unlock-veracrypt-volume.png
[2] https://tails.boum.org/contribute/reports/SponsorW/2017_12/#sprint
[3]
https://mail.gnome.org/archives/gtk-devel-list/2018-February/msg00024.html