Put transparent QWidget on top of QMediaView in QT5 on Ubuntu

Question

Goal

I want the background of my QT5 based GUI to be a video file that is playing. I also want to be able to style my GUI components with transparen

Answer 1

I know this is an old question and you managed to solve your problem by converting parts of your application to QML/QtQuick 2.2 but I ended up bumping into it by google search and someone else with the same problem might also find this. I found a solution that worked for me and has been tested on Windows with QT 5.3.

What I did was use a QGraphicsView to display the video. Here's my code (playerScreen is the QGraphicsView):

QGraphicsVideoItem *item = new QGraphicsVideoItem;
item->setSize(ui->playerScreen->size());
player.reset(new QMediaPlayer());
player->setVideoOutput(item);
QGraphicsScene *scene = new QGraphicsScene(0, 0, ui->playerScreen->size().width(), ui->playerScreen->size().height());
ui->playerScreen->setScene(scene);
ui->playerScreen->scene()->addItem(item);

I disabled the scroll bars on playerScreen otherwise there would be horizontal and vertical scrollbars.

I have a QWidget on top of the playerScreen in which I draw with QPainter. That QWidget is on top of the graphics view.

Then, when I play the video, I call ui->playerScreen-show(). I do this only on play because I have another screen on top (for another stuff related to my project) and I need to call show/hide when the video is being used/not used :)

Let me know if you need more information on my code.