QML and DBus in plasma

[Weng Xuetian]

Hello Plasma world,
I'm not quite familiar with plasmoid implementation, but I'd like to
implement something in plasma with DBus.
Actually I'm a input method developer, and I plan to rewrite/pick up
kimpanel in kdeplasma-addons. Currently it seems that nobody maintains
it anymore (I tried to communicate with the origin author but no reply
serval month ago), and there is some known bug that really annoying
and make it unusable...

I'm not going to change the protocol (current DBus interface) that it
communicates with input method (Since that would requires other IM
changes code and current protocol is good to work). I have learned
that plasma has add QML support (And yes I already tries to write a
simple plasmoid with QML), but for QML, seems it lacks direct DBus
support and need some C++ wrapper for it. So dataengine comes into my
head, but I found that dataengine might not suitable for this, because
kimpanel get updates only when IM notifies it via DBus, so it doesn't
need a interval to check.

So I'd like to know that is the dataengine has some way to "push" the
changes to plasmoid? Or for such dbus application, is the QtDBus and
C++ the only choice? (Sorry but I don't know anything of Python..).

Regards,