如何在Qt5中通过模型/视图/委托使用自定义小部件？

#include <QStyledItemDelegate>
#include <QPushButton>

class ButtonDelegate : public QStyledItemDelegate {
    Q_OBJECT
public:
    ButtonDelegate(QObject *parent = nullptr) : QStyledItemDelegate(parent) {}

    void paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const override {
        if (index.data().canConvert<QPushButton*>()) {
            QPushButton *button = index.data().value<QPushButton*>();
            button->render(painter, option.rect.topLeft());
        } else {
            QStyledItemDelegate::paint(painter, option, index);
        }
    }

    QSize sizeHint(const QStyleOptionViewItem &option, const QModelIndex &index) const override {
        if (index.data().canConvert<QPushButton*>()) {
            QPushButton *button = index.data().value<QPushButton*>();
            return button->sizeHint();
        } else {
            return QStyledItemDelegate::sizeHint(option, index);
        }
    }

    QWidget *createEditor(QWidget *parent, const QStyleOptionViewItem &option, const QModelIndex &index) const override {
        QPushButton *button = new QPushButton(parent);
        button->setText(index.data().toString());
        return button;
    }

    void setEditorData(QWidget *editor, const QModelIndex &index) const override {
        QPushButton *button = qobject_cast<QPushButton*>(editor);
        if (button) {
            button->setText(index.data().toString());
        }
    }

    void setModelData(QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const override {
        QPushButton *button = qobject_cast<QPushButton*>(editor);
        if (button) {
            model->setData(index, button->text());
        }
    }

    void updateEditorGeometry(QWidget *editor, const QStyleOptionViewItem &option, const QModelIndex &index) const override {
        editor->setGeometry(option.rect);
    }
};

#include <QStandardItemModel>
#include <QListView>

int main(int argc, char *argv[]) {
    QApplication app(argc, argv);

    QStandardItemModel model;
    QListView view;

    // 添加一些数据
    for (int i = 0; i < 10; ++i) {
        QStandardItem *item = new QStandardItem(QString("Item %1").arg(i));
        model.appendRow(item);
    }

    // 设置自定义委托
    ButtonDelegate delegate;
    view.setItemDelegate(&delegate);

    view.setModel(&model);
    view.show();

    return app.exec();
}