通过QStyledItemDelegate以不同的颜色显示QTableWidgetItem的文本

#include <QApplication>
#include <QTableWidget>
#include <QStyledItemDelegate>
#include <QPainter>

class ColorDelegate : public QStyledItemDelegate {
public:
    void paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const override {
        QStyleOptionViewItem opt = option;
        initStyleOption(&opt, index);

        // 根据单元格内容设置颜色
        if (index.data().toString() == "重要") {
            opt.palette.setColor(QPalette::Text, Qt::red);
        } else {
            opt.palette.setColor(QPalette::Text, Qt::black);
        }

        QApplication::style()->drawControl(QStyle::CE_ItemViewItem, &opt, painter);
    }
};

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

    QTableWidget tableWidget(4, 2);
    ColorDelegate delegate;

    tableWidget.setItemDelegate(&delegate);

    // 填充数据并测试颜色显示
    tableWidget.setItem(0, 0, new QTableWidgetItem("普通"));
    tableWidget.setItem(1, 0, new QTableWidgetItem("重要"));

    tableWidget.show();
    return app.exec();
}