KDE 5, Qt 5 and QML - What is advised for writing new (KDE) applications in the long term?

[Alexander Neundorf]

On Friday 12 August 2011, Mark wrote:
> Hi,
> 
> Times are interesting right now!
> - Qt is focusing heavily on Qt5.
> - KDE is focusing on KDE 5 (plasma 2 and making modules mainly)
> - QML is the new big thing!
> 
> Now for application developers like me, and probably everyone reading
> this list, some uncertainty is popping up. At least for me. This is
> specifically with QML and Qt code for KDE applications.
> 
> An example. Right now I've written a small application in QML and C++
> for managing todo items. In QML i display everything, apply fancy
> effects and such. In C++ i manage the data model and fill it from an
> external source. The questions i have here is what is "the right"
> approach these days for making an application that in time could be
> targeted for KDE SC inclusion? Note: the above example is just that,
> an example!
> 
> 1. Write the application in Qt mostly and use kdelibs where needed?
> 2. Same as 1. but make the GUI in QML like i did in the example above?
> 3. Skip C++ altogether and make in in QML only?
> .. more options?

The goal for Qt5 is to stay as close as possible to 100% source compatible to 
Qt4, so no changes required there.
For the KDE frameworks, we try to do the same, but e.g. due to some things 
getting merged into Qt we may not reach the 100%.

IOW, no major changes required in any KDE applications due to the transition 
from monolithic kdelibs to modular KDE frameworks.

Alex