videowidget.cpp Example File

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 #include "videowidget.h"

 #include "videowidgetsurface.h"

 #include <QtWidgets>
 #include <qvideosurfaceformat.h>

 VideoWidget::VideoWidget(QWidget *parent)
     : QWidget(parent)
     , surface(0)
 {
     setAutoFillBackground(false);
     setAttribute(Qt::WA_NoSystemBackground, true);
     setAttribute(Qt::WA_PaintOnScreen, true);

     QPalette palette = this->palette();
     palette.setColor(QPalette::Background, Qt::black);
     setPalette(palette);

     setSizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::MinimumExpanding);

     surface = new VideoWidgetSurface(this);
 }

 VideoWidget::~VideoWidget()
 {
     delete surface;
 }

 QSize VideoWidget::sizeHint() const
 {
     return surface->surfaceFormat().sizeHint();
 }

 void VideoWidget::paintEvent(QPaintEvent *event)
 {
     QPainter painter(this);

     if (surface->isActive()) {
         const QRect videoRect = surface->videoRect();

         if (!videoRect.contains(event->rect())) {
             QRegion region = event->region();
             region.subtract(videoRect);

             QBrush brush = palette().background();

             foreach (const QRect &rect, region.rects())
                 painter.fillRect(rect, brush);
         }

         surface->paint(&painter);
     } else {
         painter.fillRect(event->rect(), palette().background());
     }
 }

 void VideoWidget::resizeEvent(QResizeEvent *event)
 {
     QWidget::resizeEvent(event);

     surface->updateVideoRect();
 }