can't open the serial port from qt - c++

Question

I am working on a project where I have to write to an read from a serial port. I have written the following code, but I am getting the message "can't open the port" in my else statement.
When I use hercules, I can open the "COM1" port. But I don't know why can't I open this port via my QT program.
code:
widget.h:
#ifndef WIDGET_H
#define WIDGET_H
#include <QWidget>
#include <QtSerialPort/QSerialPort>
namespace Ui {
class Widget;
}
class Widget : public QWidget
{
Q_OBJECT
public:
explicit Widget(QWidget *parent = nullptr);
~Widget();
QSerialPort *serial;
private slots:
void on_pushButton_clicked();
private:
Ui::Widget *ui;
};
#endif // WIDGET_H
widget.cpp:
#include "widget.h"
#include "ui_widget.h"
#include <QDebug>
#include <QtSerialPort/QSerialPort>
#include <QSerialPortInfo>
Widget::Widget(QWidget *parent) :
QWidget(parent),
ui(new Ui::Widget)
{
ui->setupUi(this);
serial = new QSerialPort(this);
serial->setPortName("COM1");
for(const auto &serialPortInfo : QSerialPortInfo::availablePorts())
{
qDebug() << "find serial port: " << serialPortInfo.portName() ;
}
serial->open(QIODevice::ReadWrite);
if(serial->open(QIODevice::ReadWrite))
{
serial->setBaudRate(QSerialPort::Baud9600);
serial->setDataBits(QSerialPort::Data8);
serial->setParity(QSerialPort::NoParity);
serial->setStopBits(QSerialPort::OneStop);
serial->setFlowControl(QSerialPort::NoFlowControl);
while(1)
{
serial->write("ok");
qDebug() << " Reading " << serial->read(1);
serial->flush();
}
}
else
{
qDebug() << "can't open the port";
}
}
Widget::~Widget()
{
delete ui;
serial->close();
}
void Widget::on_pushButton_clicked()
{
qDebug() << "salam";
}
main.cpp:
#include "widget.h"
#include <QApplication>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
Widget w;
w.show();
return a.exec();
}

Answer 1

You do open two times, I guess second one should be isOpen