stardelegate.cpp Example File

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  #include <QtWidgets>

  #include "stardelegate.h"
  #include "stareditor.h"
  #include "starrating.h"

  void StarDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option,
                           const QModelIndex &index) const
  {
      if (index.data().canConvert<StarRating>()) {
          StarRating starRating = qvariant_cast<StarRating>(index.data());

          if (option.state & QStyle::State_Selected)
              painter->fillRect(option.rect, option.palette.highlight());

          starRating.paint(painter, option.rect, option.palette,
                           StarRating::ReadOnly);
      } else {
          QStyledItemDelegate::paint(painter, option, index);
      }
  }

  QSize StarDelegate::sizeHint(const QStyleOptionViewItem &option,
                               const QModelIndex &index) const
  {
      if (index.data().canConvert<StarRating>()) {
          StarRating starRating = qvariant_cast<StarRating>(index.data());
          return starRating.sizeHint();
      } else {
          return QStyledItemDelegate::sizeHint(option, index);
      }
  }

  QWidget *StarDelegate::createEditor(QWidget *parent,
                                      const QStyleOptionViewItem &option,
                                      const QModelIndex &index) const

  {
      if (index.data().canConvert<StarRating>()) {
          StarEditor *editor = new StarEditor(parent);
          connect(editor, &StarEditor::editingFinished,
                  this, &StarDelegate::commitAndCloseEditor);
          return editor;
      } else {
          return QStyledItemDelegate::createEditor(parent, option, index);
      }
  }

  void StarDelegate::setEditorData(QWidget *editor,
                                   const QModelIndex &index) const
  {
      if (index.data().canConvert<StarRating>()) {
          StarRating starRating = qvariant_cast<StarRating>(index.data());
          StarEditor *starEditor = qobject_cast<StarEditor *>(editor);
          starEditor->setStarRating(starRating);
      } else {
          QStyledItemDelegate::setEditorData(editor, index);
      }
  }

  void StarDelegate::setModelData(QWidget *editor, QAbstractItemModel *model,
                                  const QModelIndex &index) const
  {
      if (index.data().canConvert<StarRating>()) {
          StarEditor *starEditor = qobject_cast<StarEditor *>(editor);
          model->setData(index, QVariant::fromValue(starEditor->starRating()));
      } else {
          QStyledItemDelegate::setModelData(editor, model, index);
      }
  }

  void StarDelegate::commitAndCloseEditor()
  {
      StarEditor *editor = qobject_cast<StarEditor *>(sender());
      emit commitData(editor);
      emit closeEditor(editor);
  }