[calligra] /: Qt3Support is also needed in Calligra.

[Jaroslaw Staniek]

On 2 December 2011 10:26, Boudewijn Rempt <boud at valdyas.org> wrote:
> On Friday 02 December 2011 Dec, Jaroslaw Staniek wrote:
>> On 2 December 2011 09:25, Boudewijn Rempt <boud at valdyas.org> wrote:
>> > On Thursday 01 December 2011 Dec, Jos van den Oever wrote:
>> >> Git commit aa83cf10c9031b8bb33bc191dbacf9fab663d736 by Jos van den Oever.
>> >> Committed on 01/12/2011 at 23:36.
>> >> Pushed by vandenoever into branch 'master'.
>> >>
>> >> Qt3Support is also needed in Calligra.
>> >
>> > Hm... We really have to get rid of that, it won't be supported in Qt5 anymore. Maybe we can start by adding a switch that disables everything that links to qt3support -- something like the attached patch.
>> >
>>
>> Hi,
>> Some of qt3support use in Kexi can be removed but not from core
>> components like table view. So the dependency is unconditional.
>
> That means that Kexi won't run on OSX, and it will reach its end of life when Qt4 reaches the end of life.

I am ok with this at the current stage. Porting should be careful, you
know - Kexi 1.x on Qt 3 was way more stable, and in Qt 4 version we
have almost no extra complicated features. How about discussing about
a deadline for removal of Qt3Support? I propose

>>
>> Qt 5 is a long way, isn't it?
>
> Well, the plans are to release Qt5 in the first half of 2012. I suspect it will really quickly replace Qt4, since it's supposed to be mostly Qt4-compatible, except for removing long-standing deprecated modules. The impression I got at the Dev Days in Munich is that once Qt5 is released, Qt4 won't be supported by Nokia anymore, just by Digia. Qt4 basically dies at that point.
>
>> We have not had even single release for Qt 4.
>> I wouldn't want to see another initiatives like Trinity KOffice
>> started for Calligra/Qt4.
>
> Fortunately, the move from Qt4 to Qt5 is supposed to be much smaller than from Qt3 to Qt4 (same with the jump from KDE4 to KDE Frameworks 5, but I'm very sceptical about that.)
>

I know all the info about Qt 5 schedule and specifics of migration.
Please let me mention all the components we depend on during the
transition process:
Qt 5 could be released in May and then it will be in distros in
summer. More importantly, it will not be on many users' desktops by
summer. This is just Qt 5.0. Many devs are afraid of releasing
software using x.0 version of a new library, so that could add up to
the delay.
We don't know how the KDE 5 will be deployed so would we have a
transitional Calligra/Qt5 running on KDE/Qt4 before KDE/Qt5 arrives?
KDE/Qt5  will appear on real desktops after most applications are
ported. Will this year or more? No idea. No doubt distros would wait
for that and won't be trying to repeat the KDE 4.0 story again.

Someone may say Qt4 and Qt5 apps will be co-installable on these new
distro releases so we don't need to depend on KDEF 5 . But this also
means instead we can have Qt 4-based releases of Calligra during this
transitional (quite long) period.

We do remember there are always aspects of longer term support.
Personally I see this as a must have to be competitive. In constrast
to cases like in Qt tablet support for Krita - I full agree with you
having specific needs for bumping Qt version requirements - as said
before I see no features in Qt 5 that justifies abandoning support for
older Qt 4-oriented distros. Since this is all your time, couldn't
length of the support be specific per application? ie. some apps can
stop supporting Qt 4 and technically we're prepared for this thanks to
build options/profiles.

>>
>> Because of the current resources I am in favour of 'switch to Qt 5
>> when we're ready'. As for Kexi itself there is no feature of Qt 5 that
>> is of even secondary importance for now.
>>
>> Qt 4 will be still available in distros, I bet, for many releases.
>
> I'm not so sure of that; but in any case, I would like to be able to switch off everything that uses Qt3Support in calligra easily. Do you have a problem with having the switch in the build system?
>

Of course I don't have problem with any such switch.
I am also considering adding Kexi-only switch similar to the
Krita-only one. Both are not that trivial.
More switches-better.

-- 
regards / pozdrawiam, Jaroslaw Staniek
 http://www.linkedin.com/in/jstaniek
 Kexi & Calligra (kexi-project.org, identi.ca/kexi, calligra-suite.org)
 KDE Software Development Platform on MS Windows (windows.kde.org)