Qt Reference Documentation

# videowidget.cpp Example File

multimedia/videowidget/videowidget.cpp

     /****************************************************************************
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     ** This file is part of the examples of the Qt Toolkit.
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     #include "videowidget.h"

     #include "videowidgetsurface.h"

     #include <QtMultimedia>

     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();
     }