Mobile components and convergence

[Thomas Pfeiffer]

On Mittwoch, 23. März 2016 17:58:55 CET Sandro Andrade wrote:
> Hi there,

Hi Sandro,

> I've been playing with Qt on Android for some weeks, trying to come up
> with some nice approach to implement Minuet for Android/iOS. I'd like
> to bring some topics I've been wondering for discussion here:
> 
> * UI/UX visual language/metaphors: FWIK, we have four possible paths
> to follow regarding that:
> 
> 1) QML Quick Controls 1
> 2) QML Quick Controls 2 (with Material Design, Universal Design, and
> Default) 3) qml-material (https://github.com/papyros/qml-material)
> 4) Kirigami (https://quickgit.kde.org/?p=kirigami.git)
>
> I think all of those have its strenghts and shortcomings but it'd be
> useful if we start discussing some guidelines regarding that. Using
> Kirigami would be obviously our first choice since we'd be promoting
> our own visual language. QML Quick Controls 2 has a technical preview
> in Qt 5.6 with an initial implementation of Material Design, Universal
> Design and a "default" style for QML controls. Both Kirigami and QML
> Quick Controls 2 are in a very early stage though, I'm unsure if they
> are ready for use in real complex mobile applications.

Kirigami is obviously the way to go. It allows us to have our own interaction 
design language and it's already being used by four KDE mobile applications 
that are in the works. It would be a shame if we didn't all use it.
Subsurface-mobile [1] (not a KDE application) shows that even at this early 
stage, Kirigami is already well suited for complex applications (I guess 
Subsurface-mobile is pretty much as complex as it gets for a mobile app, 
they're doing some crazy stuff there) and is officially released on Android. 

Kirigami alone is not the solution, however, since it purposely does not offer 
basic controls. It's meant as an add-on for Qt Quick Controls, offering more 
high-level building blocks. Currently it's based on QQC 1, but it will switch 
to QQC 2 as soon as those are ready for prime-time. 

> OTOH, qml-material looks great but it's been barely maintained. I
> don't know if replacing a given UX visual language by another one is
> as simple as changing the QML style adopted or if they define
> different vocabulary which, in turn, would end up with the need of
> changing the source code and the particular UML elements adopted. At
> least in QML Quick Controls 2, we can easily choose between Material
> Design, Universal Design, and the Default Design requiring only an app
> restart. Having a standardized vocabulary with the possibility of
> implementing UX visual languages as simple styles would be the perfect
> scenario.

Kirigami allows theming as well, that it should have you covered there.

> * KF5-based vs Qt-based: I haven't tried to build KF5 on Android yet,
> but I'd like to discuss to which extent they're buildable in Android
> and actually bring some quite useful functionality. Has anyone
> successfully built KF5 on Android? At the minimal, level 1 frameworks
> shouldn't present any issue apart from setting up cmake environment?

Kirigami is developed with the clear goal of being deployable on Android and 
iOS and will become a Tier 1 KDE Framework. I personally don't know about 
other Frameworks.

> * Release and Deployment: has anyone tried to deploy qt apps with
> ministro service? If we're going to have a set of qt-based
> applications for Android, the bundled deployment option doesn't seem
> viable. We have a store in Google App Store for KDE applications
> (https://play.google.com/store/apps/developer?id=KDE%20Community&hl=pt_BR),
> currently providing mobile versions of KAlgebra, KDE Connect, and
> Behaim Globe (marble-based?). Also, we have the recent aquisition of
> OCS by BlueSystems.

Play Store is certainly the easiest way to reach most users. OCS is also a 
possible option for the future, but will require users to explicitly allow 
sideloading of APKs (if their system even allows them to do that).

Cheers,
Thomas

[1] https://subsurface-divelog.org/2016/03/announcing-subsurface-mobile-for-android/