构造函数是私有的吗？

#ifndef MYMODEL_H
#define MYMODEL_H

#include <QStandardItemModel>

class myModel : public QStandardItemModel
{
public:
    Q_OBJECT

    myModel(QObject *parent = 0);
};

#endif // MYMODEL_H

#include \"mymodel.h\"

myModel::myModel(QObject *parent) :
    QStandardItemModel(parent)
{

}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow();

private slots:
    ...

signals:
    ...

private:
    ...
    myModel *model;
};

void MainWindow::createModel()
{
    model = new myModel(this);