[Development] How to speed up QML for KDE5 without QML compiler

[Leslie Zhai]

Hi great Qt and KDE developers,

I like QML, it is high speed development language, easy to create candy 
UI and not difficult to debug. KDE4 began to use it in some projects, 
for example, KScreen`s kcm module, it used QML to take place of 
traditional QWidget. and KDE5, it is full of QML, for example, kwin`s 
tabbox, plasma-desktop and plasma-workspace`s applet, sddm, etc.

For a new PC,  there is no sharp difference between QML and QWidget, but 
in a very very old PC, how old? about 7 years ago, QML is very slow! and 
it needs to close all effects for KDE5, even that when clicked, for 
example, calendar applet, it hang about 3+ seconds to showPopup.

There is commercial QML compiler, a very small example tried to use it 
https://github.com/AOSC-Dev/AOSC-VersionHelper2
But is it suitable for huge projects just like KDE5 if bought a 
commercial license? because not all KF5 components follow the Qt Quick 
Compiler`s resource.qrc way, so is it able to compile? for example, 
kickoff applet (the start menu of KDE5).

-- 
Regards,
Leslie Zhai - a KDE developer