Bug 502026

Summary:	Open with default application does not open the default application specified for the mime type (darktable)
Product:	[Applications] digikam	Reporter:	KaiB <kaizubg>
Component:	Usability-OpenWith	Assignee:	Digikam Developers <digikam-bugs-null>
Status:	REPORTED ---
Severity:	normal	CC:	caulier.gilles, metzpinguin
Priority:	NOR
Version First Reported In:	8.6.0
Target Milestone:	---
Platform:	Fedora RPMs
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description KaiB 2025-03-26 15:06:12 UTC

SUMMARY
Want to start my raw processor (darktable) from the toolbar or from the keyboard short cut.  

STEPS TO REPRODUCE
1. In Gnome Files the NRW file type has been linked to darktable.
2. Select RAW file (Nikon NRW file)
3. Push Button - Open With Default Application (same observed with keyboard short cut Ctrl-F4)

OBSERVED RESULT
Digikam opens the Gnome Document viewer with an error message.

EXPECTED RESULT
Should open Darktable (v.5.0.1) that is installed on t
he system and defined as default application for NRW file type.

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: Fedora 41; Gnome 48
KDE Plasma Version: 
KDE Frameworks Version: 
Qt Version: ?

ADDITIONAL INFORMATION
It is interesting to observe that this error situation can be observed on an program that is installed from the official Fedora Repo. On an appimage (same version & machine) application this error can not be observed. Here darktable starts without an error. Darktable starts correctly from the Open with menu option.

Comment 1 caulier.gilles 2025-03-26 15:34:33 UTC

There is certainly a native mime type settings mess on your computer about the DarkTable application properties.

The type mime work around depends of KDE framework. In you native computer, certainly not based on KDE, probably something is wrong or missing.

In the AppImage that we provide, all the necessary components are present of course...

Best

Gilles Caulier

Comment 2 KaiB 2025-03-26 19:59:34 UTC

(In reply to caulier.gilles from comment #1)
> There is certainly a native mime type settings mess on your computer about
> the DarkTable application properties.

Double clicking on a NRW file in the Gnome Files or in Gnome commander, opens the file in Darktable correctly. 

A mystery for me.

Regards, Kai

Seems to stay a
> 
> The type mime work around depends of KDE framework. In you native computer,
> certainly not based on KDE, probably something is wrong or missing.
> 
> In the AppImage that we provide, all the necessary components are present of
> course...
> 
> Best
> 
> Gilles Caulier

Comment 3 Maik Qualmann 2025-03-26 21:01:23 UTC

We use a simple Qt function (QDesktopServices::openUrl()) to open the default application. It probably doesn't work with the Gnome desktop. I don't know of any standard cross-desktop function for querying a default application.

Maik

Comment 4 KaiB 2025-03-27 06:09:06 UTC

However there seems to be a overriding mechanism to this under the hood.

Selected a NRW-File > Open With > Other > 
- searched & selected darktable
- selected option: Remember application association for all files of type "Nikon NRW raw image" (image/x-nikon-nrw)
> Clicked OK

Now the toolbar icon/functionality "Open With Default Application" opens darktable correctly. The same implies with the keyboard shortcut Ctrl-F4. 

Happy with this!

I don't know if this is universal solution. But this could be stated in the user manual where this possibility is not mentioned. Check chapter 
https://docs.digikam.org/en/main_window/image_view.html#id22.