pixeldelegate.cpp Example File

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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;
  }