May be can help me...
The method seek () doesn't work

I check:
Qt Code:
  1. bool bOk = mediaObject-> isSeekable ();
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Returns false.

But widget SeekSlider Works and allows to change video position!
Qt Code:
  1. mediaObject = ui.vpPreview->mediaObject();
  2. mediaObject->setTickInterval(20);
  3. ui.seekSlider->setMediaObject(ui.vpPreview->mediaObject());
  4. ui.seekSlider->show();
  5. connect(mediaObject, SIGNAL(tick(qint64)), this, SLOT(state(qint64)));
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