Find the current port and open it

[deleted286]

I want to add all current ports into o combo box, and open the selected one.
in open_serial(), currentport name returns empty always. How can i do it?

```
  ui->ports->clear();
  foreach (const QSerialPortInfo &info, QSerialPortInfo::availablePorts()) {
      list << info.portName();
      ui->ports->addItem(info.portName());
    }
  currentPortName = ui->ports->currentText();
  }

  MainWindow::~MainWindow()
 {
delete ui;
if (serial && serial->isOpen())
{
    serial->close();
    delete serial;
}
delete dizi_mtx;
 }

void MainWindow::open_Serial()
  {
serial->setPortName(ui->ports->currentText());
//serial->setPortName("/dev/ttyUSB0");
serial->setBaudRate(QSerialPort::Baud115200);
serial->setDataBits(QSerialPort::Data8);
serial->setParity(QSerialPort::NoParity);
serial->setStopBits(QSerialPort::OneStop);
serial->setFlowControl(QSerialPort::NoFlowControl);

if (serial->open(QIODevice::ReadWrite))
{
    qDebug() << currentPortName << "is Open ";
    serial->clear();
    write_Json();
    connect(serial, &QSerialPort::readyRead, this, &MainWindow::on_Serial_Read);
}

if(serial->isOpen())
{
    ui->Open->setChecked(true);
}
else
{
    ui->Close->setChecked(true);
 }

}

[jsulm]

@suslucoder said in Find the current port and open it:

currentport name returns empty always

So, is anything selected?

[deleted286]

@jsulm but it was selected

[jsulm]

@suslucoder I mean: is a port selected in combo box (or what ever widget ui->ports is)?

[deleted286]

@jsulm yes it was selected

[jsulm]

@suslucoder How do you know that ui->ports->currentText() returns an empty string?

[deleted286]

@jsulm from here

if (serial->open(QIODevice::ReadWrite))
{
    qDebug() << currentPortName << "is Open ";
    serial->clear();
    write_Json();
    connect(serial, &QSerialPort::readyRead, this, &MainWindow::on_Serial_Read);
}

[Christian Ehrlicher]

@suslucoder You don't use ui->ports->currentText() anywhere in your code you show us here ...

[jsulm]

@suslucoder said in Find the current port and open it:

currentPortName

If you mean this one, then this is wrong as you only set it once when nothing is selected! Use ui->ports->currentText():

qDebug() << ui->ports->currentText() << "is Open ";

[deleted286]

@Christian-Ehrlicher im using it to open the port?

serial->setPortName(ui->ports->currentText());

[deleted286]

@jsulm it returns empty again

[jsulm]

@suslucoder said in Find the current port and open it:

it returns empty again

How did you verify that?
Please add

qDebug() << ui->ports->currentText();

and see what it prints out.

[deleted286]

@jsulm said in Find the current port and open it:

qDebug() << ui->ports->currentText();

I've add it. It returns empty string.
Like ""
Why you didnt believe me?

[jsulm]

@suslucoder said in Find the current port and open it:

Why you didnt believe me?

Because it was not clear how you actually verified that it is indeed empty. Often people simply assume something, that's why it's worth asking.

[Christian Ehrlicher]

Please output also the count and the current index of the combobox. Is it really filled? Do you create it two times by accident?