How can I store data Received via serial communication to text file?

[segtteee]

@ambershark
it is here

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    mSerialport = new QSerialPort (this);
    connect(mSerialport,SIGNAL(readyRead()),this,SLOT(read_device_data()));
}
////
void MainWindow::on_pushButton_connect_clicked()
{
if (mSerialport->open(QIODevice::ReadWrite))
    {
        QMessageBox::information(this,tr("connect"),"Serial communication start");
    }
    else
    {
        QMessageBox::critical(this,tr("error"),mSerialport->errorString());
    }
}
///
void MainWindow::read_device_data()
{
    QByteArray device_data(mSerialport->readAll());
    ui->data_show->setText(device_data);


    double number = QString(device_data).remove('\n').toDouble() * 1000;
    qDebug() << number;
    ui->dial->setValue(number);
}

[ambershark]

@J.Hilk Lol yea I was being lazy.. In real code I never do that. To be fair though it will close automatically when QFile goes out of scope. :)

[ambershark]

Ok so here is how I would do it to fit with your code:

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    mSerialport = new QSerialPort (this);
    connect(mSerialport,SIGNAL(readyRead()),this,SLOT(read_device_data()));
}
////
void MainWindow::on_pushButton_connect_clicked()
{
if (mSerialport->open(QIODevice::ReadWrite))
    {
        QMessageBox::information(this,tr("connect"),"Serial communication start");
    }
    else
    {
        QMessageBox::critical(this,tr("error"),mSerialport->errorString());
    }
}
///
void MainWindow::read_device_data()
{
    QByteArray device_data(mSerialport->readAll());
    ui->data_show->setText(device_data);
    if (!writeDataToFile(device_data))
        qDebug() << "Failed to open file";


    double number = QString(device_data).remove('\n').toDouble() * 1000;
    qDebug() << number;
    ui->dial->setValue(number);
}

bool MainWindow::writeDataToFile(const QByteArray &data)
{
   QFile f("yourfile.txt");
   if (!f.open(QIODevice::WriteOnly | QIODevice::Text))
      return false; // failed to open

   QTextStream out(&f);
   out << data << endl;

   f.close() // for you J.Hilk ;)

   return true;
}

[segtteee]

@ambershark

Where should I declare "writeDataTofile"? header's public?

[jsulm]

@J.Hilk QFile automatically closes the file when it is destroyed :-)

[jsulm]

@segtteee said in How can I store data Received via serial communication to text file?:

header's public

Why public? It is only needed inside MainWindow, so it should not be public.

[segtteee]

@jsulm said in How can I store data Received via serial communication to text file?:

@segtteee said in How can I store data Received via serial communication to text file?:

header's public

but "‘writeDataToFile’ was not declared in this scope
if (!writeDataToFile(device_data))" is displayed.
declaring "writeDataTofile" is need

[jsulm]

@segtteee Then declare it in the private section of the class, what is the problem?

[segtteee]

@jsulm
but ambershark informed them that I wrote them separately. Is it not the declaration that starts with bool? Should I combine these two?

[jsulm]

@segtteee You should learn C++.

// Header file
class MainWindow
{
private:
    // This is declaration
    bool writeDataToFile(const QByteArray &data)
};

// C++ file
// This is definition
bool MainWindow::writeDataToFile(const QByteArray &data)
{
    ...
}