How to make a transparent QWidget over a Phonon Video?

[linus]

Hi!

Om working on a project thats showing a mpeg-file using phonon. I would like to place a transparent QWidget over my video so i can click and paint on it. I managed to put a QWidget above the video and i can click with the mouse and paint on it but its not transparent.

Any ideas how to make it transparent?

Heres my Overlay QWidget:

#include <QtGui>
#include "videoarea.h"
 
VideoArea::VideoArea(QWidget *parent) :
        QWidget(parent)
{
    this->setWindowOpacity(1.0);
}
void VideoArea::mousePressEvent(QMouseEvent *event)
{
    if (event->button() == Qt::LeftButton) {
        qDebug("Mouse click: X: %d Y: %d", event->x(), event->y());
        crossList.append(QPoint(event->x(), event->y()));
        paintCross();
    }
}
 
void VideoArea::paintCross()
{
    update();
}
 
 
void VideoArea::paintEvent(QPaintEvent *)
{
    QPainter painter(this);
    painter.setPen(QPen(Qt::red, 1, Qt::DashDotLine, Qt::RoundCap));
 
    for (int i = 0; i < crossList.size(); ++i)
    {
        painter.drawLine(crossList.at(i).x(), crossList.at(i).y()+10, crossList.at(i).x(), crossList.at(i).y()-10);
        painter.drawLine(crossList.at(i).x()+10, crossList.at(i).y(), crossList.at(i).x()-10, crossList.at(i).y());
    }
}

#include <QtGui>
#include "videoarea.h"

VideoArea::VideoArea(QWidget *parent) :
        QWidget(parent)
{
    this->setWindowOpacity(1.0);
}
void VideoArea::mousePressEvent(QMouseEvent *event)
{
    if (event->button() == Qt::LeftButton) {
        qDebug("Mouse click: X: %d Y: %d", event->x(), event->y());
        crossList.append(QPoint(event->x(), event->y()));
        paintCross();
    }
}

void VideoArea::paintCross()
{
    update();
}


void VideoArea::paintEvent(QPaintEvent *)
{
    QPainter painter(this);
    painter.setPen(QPen(Qt::red, 1, Qt::DashDotLine, Qt::RoundCap));

    for (int i = 0; i < crossList.size(); ++i)
    {
        painter.drawLine(crossList.at(i).x(), crossList.at(i).y()+10, crossList.at(i).x(), crossList.at(i).y()-10);
        painter.drawLine(crossList.at(i).x()+10, crossList.at(i).y(), crossList.at(i).x()-10, crossList.at(i).y());
    }
}

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[zgulser]

try pen.setColor(Qt::transparent);

[aamer4yu]

Why dont you override the video widget itself ? You will need to call the base class paintEvent first and then your lines drawing code.
That way you can still draw over the video, isnt it

[linus]

Why dont you override the video widget itself ? You will need to call the base class paintEvent first and then your lines drawing code.
That way you can still draw over the video, isnt it

I did this first but it didnt work, all i saw was the videostream.

[linus]

try pen.setColor(Qt::transparent);

On my painter? I tried it and all it did was to make my painting transparent, not the background.

[zgulser]

Pardon me,

what about widget->setStyleSheet("background-color: rgb(0,0,0,0)"); ?

You can do it from the designer as well.

[aamer4yu]

I did this first but it didnt work, all i saw was the videostream.

I guess it might be tricky. I guess the phonon will use directX and directX will render directly on memory buffer,,, so am afraid you cant do it directly.. I will try if i get some time...
till then hope someone else comes to rescue

[linus]

I guess it might be tricky. I guess the phonon will use directX and directX will render directly on memory buffer,,, so am afraid you cant do it directly.. I will try if i get some time...
till then hope someone else comes to rescue

Ok, thanks. Appreciate it!

[linus]

Pardon me,

what about widget->setStyleSheet("background-color: rgb(0,0,0,0)"); ?

You can do it from the designer as well.

I tried it and it didnt work, thanks anyway.