Контекстное меню Qt

void insertNewRowAfterCurrent(QTableWidget* tableWidget)
{
    tableWidget->removeRow(tableWidget->currentRow() + 1);
}
void insertNewRowBeforeCurrent(QTableWidget* tableWidget)
{
    tableWidget->removeRow(tableWidget->currentRow() - 1);
}
void removeCurrentRow(QTableWidget* tableWidget)
{
     tableWidget->removeRow(tableWidget->currentRow());
}

QLineEdit menu(&tableWidget);
    QAction* aInsertNewRowAfterCurrent;
    QAction* aInsertNewRowBeforeCurrent;
    QAction* aRemoveCurrentRow;
 
    aInsertNewRowAfterCurrent = new QAction(QObject::tr("Insert new row after current"),&menu);
    aInsertNewRowBeforeCurrent = new QAction(QObject::tr("Insert new row before current"),&menu);
    aRemoveCurrentRow = new QAction(QObject::tr("Remove current row"),&menu);
    menu.addAction(aInsertNewRowAfterCurrent);
    menu.addAction(aInsertNewRowBeforeCurrent);
    menu.addAction(aRemoveCurrentRow);
    menu.setContextMenuPolicy(Qt::ActionsContextMenu);
 
    menu.connect(aInsertNewRowAfterCurrent, SIGNAL(triggered(QAction*)), &tableWidget, SLOT(insertNewRowAfterCurrent()));
    menu.connect(aInsertNewRowBeforeCurrent, SIGNAL(triggered(QAction*)), &tableWidget, SLOT(insertNewRowBeforeCurrent()));
    menu.connect(aRemoveCurrentRow, SIGNAL(triggered(QAction*)), &tableWidget, SLOT(removeCurrentRow()));

 QApplication app(argc, argv);
    QTableWidget tableWidget(0,0);

class CarsTableView : public QAbstractTableModel

#ifndef CARSTABLEVIEW_H
#define CARSTABLEVIEW_H
 
#include <QtWidgets>
#include <QStandardItem>
 
class TableModel : public QAbstractTableModel 
{
public:
    TableModel::TableModel(int rows, int columns, QObject* object = 0);
        
    QVariant data(const QModelIndex& index, int role) const;
    bool setData(const QModelIndex& index, const QVariant& value, int role);
    int rowCount(const QModelIndex&) const;
 
    int columnCount(const QModelIndex&) const;
 
    Qt::ItemFlags flags(const QModelIndex& index) const;
private:
    int mRows;
    int mColumns;
    QHash<QModelIndex, QVariant> mHash;
    
};
class CarsTableView : public TableModel
{
    Q_OBJECT
public:
    CarsTableView(QWidget *parent = 0);
 
private slots:
    void insertNewRowAfterCurrent();
    void insertNewRowBeforeCurrent();
    void removeCurrentRow();
 
    void showCustomContextMenu(QPoint pos);
 
protected:
    void closeEvent(QCloseEvent* event);
 
private:
    void load();
    void write();
    void createContextMenu();
 
    QTableView* mTableView;
    QMenu* mContextMenu;
};
 
#endif // CARSTABLEVIEW_H

class CarsTableView : public TableModel

CarsTableView::CarsTableView(QWidget* parent)
    : TableModel(parent)
    , mTableView(nullptr)
    , mContextMenu(nullptr)

TableModel::TableModel(int rows, int columns, QObject* object = 0);

rowCount(nullptr)

class CarsTableView : public QTableView
{
    Q_OBJECT
public:
    CarsTableView(QTableView *parent = 0);

int TableModel::rowCount(const QModelIndex&) const
{
    return mRows;
}
 
int TableModel::columnCount(const QModelIndex&) const
{
    return mColumns;
}

QString fileName{};

QString fileName;

fileName = "";