Qt 5.6 | Qt Widgets | Pixelator Example | pixeldelegate.cpp Example File

Qt 5.6.2 Reference Documentation

# pixeldelegate.cpp Example File

itemviews/pixelator/pixeldelegate.cpp

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      #include "pixeldelegate.h"

      #include <QPainter>

      PixelDelegate::PixelDelegate(QObject *parent)
          : QAbstractItemDelegate(parent)
      {
          pixelSize = 12;
      }

      void PixelDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option,
                                const QModelIndex &index) const
      {
          if (option.state & QStyle::State_Selected)
              painter->fillRect(option.rect, option.palette.highlight());

          int size = qMin(option.rect.width(), option.rect.height());
          int brightness = index.model()->data(index, Qt::DisplayRole).toInt();
          double radius = (size / 2.0) - (brightness / 255.0 * size / 2.0);
          if (radius == 0.0)
              return;

          painter->save();
          painter->setRenderHint(QPainter::Antialiasing, true);
          painter->setPen(Qt::NoPen);
          if (option.state & QStyle::State_Selected)
              painter->setBrush(option.palette.highlightedText());
          else
              painter->setBrush(option.palette.text());

          painter->drawEllipse(QRectF(option.rect.x() + option.rect.width() / 2 - radius,
                                      option.rect.y() + option.rect.height() / 2 - radius,
                                      2 * radius, 2 * radius));
          painter->restore();
      }

      QSize PixelDelegate::sizeHint(const QStyleOptionViewItem & /* option */,
                                    const QModelIndex & /* index */) const
      {
          return QSize(pixelSize, pixelSize);
      }

      void PixelDelegate::setPixelSize(int size)
      {
          pixelSize = size;
      }