Passing variables while function is triggered by a slot

Dummie1138

Hi. Per my understanding, many function calls in Qt can be replaced with signals and slots. I have the following code:

void TestConfig::on_pushButton_New_clicked()
{
 inputBox = new QDialog(this);
    //Set size of QDialog.
    QGridLayout *gridLayout = new QGridLayout(this);
    inputBox->setLayout(gridLayout);

    //QLabel
    QLabel *boxText = new QLabel(this);
    boxText->setText("Input new test presets:");
    boxText->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Minimum);
    boxText->setAlignment(Qt::AlignCenter);
    gridLayout->addWidget(boxText, 0, 0, 1, 2, Qt::AlignCenter);

    //Add a QLineEdit
    nameInput = new QLineEdit;
    gridLayout->addWidget(nameInput, 1, 1);

   //Add a QLineEdit
    startTempInput = new QLineEdit;
    gridLayout->addWidget(startTempInput, 2, 1);

    QLineEdit *expFlashptInput = new QLineEdit;
    gridLayout->addWidget(expFlashptInput, 3, 1);

    //Add a QDialogButtonBox
    QDialogButtonBox *boxButton = new QDialogButtonBox(QDialogButtonBox::Ok, this);
    gridLayout->addWidget(boxButton, 4, 0, 1, 2, Qt::AlignCenter);
    //Read information
    connect(boxButton, SIGNAL(accepted()), this, SLOT(setTestConfig()));
    connect(boxButton, SIGNAL(accepted()), inputBox, SLOT(accept()));
}

void TestConfig::setTestConfig(){
    qDebug() << "In sTestC";
    int startTemp = startTempInput->text().toInt();
    int expFlashptTemp = expFlashptInput->text().toInt();
    qDebug() << startTemp;
    qDebug() << endTemp;
    ConfigLibrarian librarian;
    ConfigurationSet config;
    config.name = nameInput->text();
    config.serialNum = "desktop";
    config.startTemp = startTempInput->text().toInt();
    config.endTemp = 86;
    config.tempRate = 5.5;
    config.igniteFreq = 10;
    config.pressureThresh = 20;
    config.minTempAboveIni = 10;
}

In this code in order to pass data in startTempInput and expFlashptInput through, I had to declare them out of the function, which is something I am trying to avoid since the class they are built in is getting bigger. I was wondering whether there is a way to pass variables through to a slot when triggered by a signal.

I am aware that in the documentation it is listed I can't do this:
connect(sender, SIGNAL(destroyed()), this, SLOT(objectDestroyed(QObject*)));
Hence, I am wondering whether a workaround that doesn't involve declaring the variables in the class.

Please let me know if more info is required.

sierdzio

You can use a lambda for that.

connect(boxButton, &QButtonBox::accepted, this, [this, startTempInput, expFlashptInput]() {
    int startTemp = startTempInput->text().toInt();
    int expFlashptTemp = expFlashptInput->text().toInt();
    qDebug() << startTemp;
    qDebug() << endTemp;
    // ...
});