I'm an linux user. When I input Japanese text in the editor with ibus (input method framework for linux), I can't see any preedit text on screen. After I pressed enter to settle preedit text, I can see what I wrote.
I tried to fix this problem and I found QEditor::inputMethodEvent function in qcodeedit/lib/qeditor.cpp. I found a part of this function isn't work due to #ifdef Q_WS_MAC. Codes between #ifdef Q_WS_MAC and #endif only works on Mac OS.
After a bit coding and debugging, I fixed this problem. I checked that Japanese input works good on Kubuntu.
But I can't understand why the code is disabled by #ifdef Q_WS_MAC. Is there any reason?
patch is here : http://pastebin.ubuntu.com/6002384/