Qt Reference Documentation

# bookdelegate.cpp Example File

demos/books/bookdelegate.cpp

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     #include "bookdelegate.h"

     #include <QtGui>

     BookDelegate::BookDelegate(QObject *parent)
         : QSqlRelationalDelegate(parent), star(QPixmap(":images/star.png"))
     {
     }

     void BookDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option,
                                const QModelIndex &index) const
     {
         if (index.column() != 5) {
             QStyleOptionViewItemV3 opt = option;
             opt.rect.adjust(0, 0, -1, -1); // since we draw the grid ourselves
             QSqlRelationalDelegate::paint(painter, opt, index);
         } else {
             const QAbstractItemModel *model = index.model();
             QPalette::ColorGroup cg = (option.state & QStyle::State_Enabled) ?
                 (option.state & QStyle::State_Active) ? QPalette::Normal : QPalette::Inactive : QPalette::Disabled;

             if (option.state & QStyle::State_Selected)
                 painter->fillRect(option.rect, option.palette.color(cg, QPalette::Highlight));

             int rating = model->data(index, Qt::DisplayRole).toInt();
             int width = star.width();
             int height = star.height();
             int x = option.rect.x();
             int y = option.rect.y() + (option.rect.height() / 2) - (height / 2);
             for (int i = 0; i < rating; ++i) {
                 painter->drawPixmap(x, y, star);
                 x += width;
             }
             drawFocus(painter, option, option.rect.adjusted(0, 0, -1, -1)); // since we draw the grid ourselves
         }

         QPen pen = painter->pen();
         painter->setPen(option.palette.color(QPalette::Mid));
         painter->drawLine(option.rect.bottomLeft(), option.rect.bottomRight());
         painter->drawLine(option.rect.topRight(), option.rect.bottomRight());
         painter->setPen(pen);
     }

     QSize BookDelegate::sizeHint(const QStyleOptionViewItem &option,
                                      const QModelIndex &index) const
     {
         if (index.column() == 5)
             return QSize(5 * star.width(), star.height()) + QSize(1, 1);

         return QSqlRelationalDelegate::sizeHint(option, index) + QSize(1, 1); // since we draw the grid ourselves
     }

     bool BookDelegate::editorEvent(QEvent *event, QAbstractItemModel *model,
                                    const QStyleOptionViewItem &option,
                                    const QModelIndex &index)
     {
         if (index.column() != 5)
             return QSqlRelationalDelegate::editorEvent(event, model, option, index);

         if (event->type() == QEvent::MouseButtonPress) {
             QMouseEvent *mouseEvent = static_cast<QMouseEvent*>(event);
             int stars = qBound(0, int(0.7 + qreal(mouseEvent->pos().x()
                 - option.rect.x()) / star.width()), 5);
             model->setData(index, QVariant(stars));
             return false; //so that the selection can change
         }

         return true;
     }

     QWidget *BookDelegate::createEditor(QWidget *parent, const QStyleOptionViewItem &option,
                                         const QModelIndex &index) const
     {
         if (index.column() != 4)
             return QSqlRelationalDelegate::createEditor(parent, option, index);

         // for editing the year, return a spinbox with a range from -1000 to 2100.
         QSpinBox *sb = new QSpinBox(parent);
         sb->setFrame(false);
         sb->setMaximum(2100);
         sb->setMinimum(-1000);

         return sb;
     }