[KDE/Mac] Thoughts on standard directories in Qt5 - QStandardPaths

[Ian Wadham]

Hi René,

On 06/12/2014, at 11:51 PM, René J.V. Bertin wrote:
> On Saturday December 06 2014 15:50:43 Ian Wadham wrote:
>> /Applications/MacPorts/KDE4.  This might not matter much.  How often does one Qt or
>> KDE application go looking for another application?
> 
> Standard Qt applications usually don't, but lots of KDE applications do, either directly or indirectly.

A. When it crashes.  I should have known that… :-)  KCrash goes looking for Dr Konqi…

Also, I later found that the QStandardPaths code uses its ApplicationsLocation type internally,
so it HAS to pick up where the application is actually installed (e.g. /Applications/MacPorts/KF5),
unles we rewrite the QSP code a little…

> Which reminds me: whatever changes are proposed, they'll have to be compatible with dbus and related ports.

True.  That aspect would have to be rigorously tested.

>> list and make some decisions.  This could also have a bearing on how to make Qt5/KF5
>> co-installable with Qt4/KDE4 when the time comes.
> 
> It certainly will, but IMHO that time came when qt5-mac first appeared in MacPorts. The same concurrency problems must have existed during the Qt3->Qt4 transition; it's really beyond me why qt4-mac hasn't been conceived from the ground up to be co-installable with future versions.

I guess the Qt guys rely on you setting $QTDIR(?), but that is not so straightforward in
an Apple OS X desktop…

BTW, KDE software is releasing KDE Applications 14.12 on 17 December, see:
https://techbase.kde.org/Schedules/Applications/14.12_Release_Schedule
It will include a mix of KDE4 apps and ported KF5 apps.  It will be interesting to
know how they have handled co-installation and how the distros will manage.

>> problem.  A simple game like Bovo fails to find its menu config files and its graphics
>> theme files, so it paints a blank menu-less window and then crashes.
> 
> Couldn't you find a more generically useful example application among kde-baseapps?

Errrmmm, no.  I am the doyen of the KDE Games group and I will defend to the death my
right to write games.  I had enough of "useful" apps when I was working… :-)

Marko and I picked Bovo because I know the code base of KDE Games well and Bovo had
been the the only game (at the time) to be ported to KF5.  It had relatively simple dependencies
on KDE libs, so startup problems in KF5 and OS X would be relatively easy to diagnose.

It's the physicist in me, I suppose.  Keep the experiment as simple as possible…  Ideally,
I would have gone for a KF5/Qt5 version of "Hello World!", had one been available… :-)

Cheers, Ian W.