phonon not work on raspberry

[iskenderoguz]

I write a basic Qt video player with Qt 4.8.6. In my labtop there is no problem but video did not play in raspberry. I tried omxplayer and it played video. But phonon did not work. I installed phonon, phonon-backend-gstreamer and phonon-backend-vlc packages on raspberry.

How can I play video on raspberry ?
I use raspbian.

my code:

QString url = QApplication::applicationDirPath()+"/video.mp4";
ui->videoPlayer->play(Phonon::MediaSource(url));