Qt撤消框架的问题示例:添加/删除项目

QUndoStack *undoStack = new QUndoStack(this);

class AddItemCommand : public QUndoCommand
{
public:
    AddItemCommand(const QString &item, QUndoCommand *parent = nullptr)
        : QUndoCommand(parent), m_item(item) {}

    void undo() override
    {
        // 撤消添加项目的操作
    }

    void redo() override
    {
        // 重新应用添加项目的操作
    }

private:
    QString m_item;
};

class RemoveItemCommand : public QUndoCommand
{
public:
    RemoveItemCommand(const QString &item, QUndoCommand *parent = nullptr)
        : QUndoCommand(parent), m_item(item) {}

    void undo() override
    {
        // 撤消删除项目的操作
    }

    void redo() override
    {
        // 重新应用删除项目的操作
    }

private:
    QString m_item;
};

void addItem(const QString &item)
{
    AddItemCommand *command = new AddItemCommand(item);
    undoStack->push(command);
}

void removeItem(const QString &item)
{
    RemoveItemCommand *command = new RemoveItemCommand(item);
    undoStack->push(command);
}

void MainWindow::createActions()
{
    QAction *undoAction = undoStack->createUndoAction(this);
    QAction *redoAction = undoStack->createRedoAction(this);

    // 将撤消和重做操作添加到菜单或工具栏中
    editMenu->addAction(undoAction);
    editMenu->addAction(redoAction);
    editToolBar->addAction(undoAction);
    editToolBar->addAction(redoAction);
}