Pass variable value from Dialog to MainWindow

[TheCipo76]

@mrjj I have tried but don't works..

ImpostazioniSP SetImp (this, BaudRate, DataBits, Parity);
    SetImp.setModal(true);
    //SetImp.exec();
    if ( SetImp.exec() == QDialog::Accepted ) {
    BaudRate=SetImp.getBaudRate();
    //DataBits = SetImp.getDataBits();
    //Parity = SetImp.getParity();
    }

in dialog:

QString ImpostazioniSP::getBaudRate() {
return BaudRate;
}

and declaration:

public:
    explicit ImpostazioniSP(QWidget *parent = nullptr, QString BaudRate="", QString DataBits="", QString Parity="");
    ~ImpostazioniSP();

    QString BaudRate, DataBits, Parity;
    QString getBaudRate();
    //QString getDataBits();
    //QString getParity();

Where i'm failing??

[aha_1980]

@TheCipo76

Where i'm failing??

Without an error message, how should we know what "doesn't work" means?

[TheCipo76]

@aha_1980 no errors but the value was not passed

i've tried both variable and widget:

QString ImpostazioniSP::getBaudRate() {
    return QString(ui->comboBox_BaudRate->currentText());
    //return BaudRate;
}

[aha_1980]

@TheCipo76 but that looks perfectly fine. the cast to QString is unneeded, by the way.

You should start the debugger to see what happens. Is the combobox filled with values?

[TheCipo76]

@aha_1980 Debugger says that value was passed fine
but variable is set to start value..

Start value 115200

in the dialog i've setted 9600

Debug print 9600

but in mainwindow BaudRate is still 115200

[SGaist]

Do you mean the MainWindow still shows the old value ? If so, are you updating the related widget once you executed your dialog ?

[TheCipo76]

@SGaist there's no widget BaudRate is only a variable (not showed in mainwindow)

[SGaist]

So if you have something like:

qDebug() << "Before" << BaudRate;
ImpostazioniSP SetImp (this, BaudRate, DataBits, Parity);
SetImp.setModal(true);
if ( SetImp.exec() == QDialog::Accepted ) {
    BaudRate = SetImp.getBaudRate();
    qDebug() << "After" << BaudRate;
}

What's the result ?

[TheCipo76]

@SGaist this is the result:

Before "115200"
After "115200"

in the dialog qdebug print 9600 (as i've setted)
but in the mainwindows result still 115200

[SGaist]

Can you show the complete code of the current version of your dialog ?

[TheCipo76]

@SGaist

#include "impostazionisp.h"
#include "ui_impostazionisp.h"
#include <QSerialPort>
#include <QSerialPortInfo>
#include <QMessageBox>
#include <QtDebug>

static const char blankString[] = QT_TRANSLATE_NOOP("SettingsDialog", "N/A");

//QSerialPort Serial;

ImpostazioniSP::ImpostazioniSP(QWidget *parent, const QString BaudRate, const QString DataBits, const QString Parity) :
    QDialog(parent),
    BaudRate(BaudRate),
    DataBits(DataBits),
    Parity(Parity),
    ui(new Ui::ImpostazioniSP)

{
    ui->setupUi(this);

    QMessageBox msg;
    ui->comboBox_Porta->clear();
    QString description;
    QString manufacturer;
    QString serialNumber;
    const auto infos = QSerialPortInfo::availablePorts();
    for (const QSerialPortInfo &info : infos) {
        QStringList list;
        description = info.description();
        manufacturer = info.manufacturer();
        serialNumber = info.serialNumber();
        list << info.portName()
             << (!description.isEmpty() ? description : blankString)
             << (!manufacturer.isEmpty() ? manufacturer : blankString)
             << (!serialNumber.isEmpty() ? serialNumber : blankString)
             << info.systemLocation()
             << (info.vendorIdentifier() ? QString::number(info.vendorIdentifier(), 16) : blankString)
             << (info.productIdentifier() ? QString::number(info.productIdentifier(), 16) : blankString);

        ui->comboBox_Porta->addItem(list.first(), list);
    }
    
    //Baud Rate
    ui->comboBox_BaudRate->addItem("9600");
    ui->comboBox_BaudRate->addItem("19200");
    ui->comboBox_BaudRate->addItem("38400");
    ui->comboBox_BaudRate->addItem("115200");
    ui->comboBox_BaudRate->setCurrentIndex(0);
    //Data Bits
    ui->comboBox_DataBits->addItem("5");
    ui->comboBox_DataBits->addItem("6");
    ui->comboBox_DataBits->addItem("7");
    ui->comboBox_DataBits->addItem("8");
     ui->comboBox_DataBits->setCurrentIndex(3);
    //Parity
    ui->comboBox_Parity->addItem("None");
    ui->comboBox_Parity->addItem("Even");
    ui->comboBox_Parity->addItem("Odd");
    ui->comboBox_Parity->addItem("Mark");
    ui->comboBox_Parity->addItem("Space");
    ui->comboBox_Parity->setCurrentIndex(0);
    //Stop Bits
    ui->comboBox_StopBits->addItem("1");
    ui->comboBox_StopBits->addItem("1.5");
    ui->comboBox_StopBits->addItem("2");
    ui->comboBox_StopBits->setCurrentIndex(0);
    //Flow Control
    ui->comboBox_FlowControl->addItem("None");
    ui->comboBox_FlowControl->addItem("RTS/CTS");
    ui->comboBox_FlowControl->addItem("XON/XOFF");
    ui->comboBox_FlowControl->setCurrentIndex(0);
}

ImpostazioniSP::~ImpostazioniSP()
{
    delete ui;
}

void ImpostazioniSP::on_pushButton_Annulla_clicked()
{
    close();
}

void ImpostazioniSP::on_pushButton_OK_clicked()
{
    QMessageBox msg;
    //Imposta Valori Variabili
    // Baud Rate
    int Baud = ui->comboBox_BaudRate->currentText().toInt();
    switch (Baud) {
        case (9600):
                    BaudRate = "9600";
                    break;
        case (19200):
                    BaudRate ="19200";
                    break;
        case (38400):
                    BaudRate = "38400";
                    break;
        case (115200):
                    BaudRate = "115200";
                    break;
        default:
                    BaudRate = "9600";
    }
    getBaudRate();
    // Data Bits
    int Bits = ui->comboBox_DataBits->currentText().toInt();
    switch (Bits) {
        case (5) :
                DataBits = "Data5";
                break;
        case (6) :
                DataBits="Data6";
                break;
        case (7) :
                DataBits="Data7";
                break;
        case (8) :
                 DataBits="Data8";
                break;
        default:
                DataBits="Data8";
    }
    // Parity
    if (ui->comboBox_Parity->currentText() == "None") Parity="NoParity";
    if (ui->comboBox_Parity->currentText() == "Even") Parity="EvenParity";
    if (ui->comboBox_Parity->currentText() == "Odd") Parity="OddParity";
    if (ui->comboBox_Parity->currentText() == "Mark") Parity="MarkParity";
    if (ui->comboBox_Parity->currentText() == "Space") Parity="SpaceParity";
    msg.setText("OK: Settaggio Impostazioni Eseguito Correttamente");
    msg.exec();
    close();
}

QString ImpostazioniSP::getBaudRate() {
    qDebug() << "BaudRate:" << BaudRate;
    return BaudRate;
}
/*
QString ImpostazioniSP::getDataBits() {
return DataBits;
}

QString ImpostazioniSP::getParity() {
return Parity;
}
*/

[mrjj]

Hi
Its a bit odd as you seem to set BaudRate in
void ImpostazioniSP::on_pushButton_OK_clicked()
so in
QString ImpostazioniSP::getBaudRate() {
qDebug() << "BaudRate:" << BaudRate;
return BaudRate;
}

does it show the value you set with comboBox_BaudRate ?

[SGaist]

Why are you using that switch ? You already have the baud rate as a string in the combo box.

As already suggest, returning the combo box selected text is shorter and less error prone.

[TheCipo76]

@mrjj Yes:
in dialog qdebug print BaudRate 9600
in mainwindow qdebug print 115200 both Before and After

[TheCipo76]

@SGaist OK, i've fixed it as you suggested

[mrjj]

@TheCipo76
Hmm that seems almost impossible :)
I must be missing something.
So function seems to return expected result.
Just to 100% sure, please try

qDebug() << "Before" << BaudRate;
ImpostazioniSP SetImp (this, BaudRate, DataBits, Parity);
SetImp.setModal(true);
if ( SetImp.exec() == QDialog::Accepted ) {
    qDebug() << "from func" << SetImp.getBaudRate();
}

and tell what "from func" says ?

[TheCipo76]

@mrjj

Before "115200" (mainwindow)
BaudRate: "9600" (dialog)

"from func" was not showed

i've modify you code:

qDebug() << "Before" << BaudRate;
    ImpostazioniSP SetImp (this, BaudRate, DataBits, Parity);
    SetImp.setModal(true);
    if ( SetImp.exec() == QDialog::Accepted ) {
        BaudRate=SetImp.getBaudRate();
    }
    qDebug() << "from func" << SetImp.getBaudRate();

and this is result:

Before "115200"
BaudRate: "9600"
BaudRate: "9600"
from func "9600"

[SGaist]

What is stranger is that @mrjj's code is mostly the same as mine :-D

Which means that you didn't accept the dialog properly. Are you clicking on some OK button the closes it ? Or are you just clicking the X button ?

[TheCipo76]

@SGaist i close the dialog as ultimate instruction of OK pushbutton

[SGaist]

You're calling close, not accept.