Edit variables from other widget of QStackedWidget

hobbyProgrammer

@jsulm Thank you! It works.

hobbyProgrammer

@jsulm on my advanced construction it doesn't seem to work.
I have a mainWindow and a QWidget. The widget contains a promoted QGraphicsView. I'd like to retreive information from the QGraphicsView to the mainWindow.
I already tried by emitting a signal in QGraphicsView and connect it in the QWidget to a slot that sets a public integer to that value and send a signal for MainWindow. Then I go to the mainWindow and connect the signal from QWidget to a slot that handles the rest.

It doesn't go to the signal in the QWidget.

this is the code in the QWidget:

#include "overview.h"
#include "ui_overview.h"

Overview::Overview(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Overview)
{
    ui->setupUi(this);
    overviewView *ovView = qobject_cast<overviewView*>(ui->graphicsView);
    connect(ovView, &overviewView::valAdded, this, &Overview::giveSignalToMainWindow);
}

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

void Overview::giveSignalToMainWindow()
{
    qDebug() << "overview";
    emit editFinished();
    val = ui->graphicsView->value;
    qDebug() << "Overview ui->graphicsView->value: "<< ui->graphicsView->value;
}

jsulm

@hobbyProgrammer I'm not sure I understand: do you mean slot connected to editFinished() is not called?

hobbyProgrammer

@jsulm No I mean that Overview::giveSignalToMainWindow is not even called.

hobbyProgrammer

void overviewView::loadFromCSV()
{
    QString fileName = "C://users//user1//downloads//data.csv";
    QFile csvFile(fileName);
    QStringList dataList;
    if(csvFile.open(QIODevice::ReadOnly))
    {
        QString data;
        data = csvFile.readAll();
        dataList = data.split('\n');
        csvFile.close();
    }

    for(int i = 0; i < dataList.size(); i++)
    {
        QString data2 = dataList.at(i);
        QStringList dataList = data2.split(",");
        for(int j = 0; j < dataList.size(); j++)
        {
            val = dataList.at(j);
        }
    }

    emit valAdded();
    qDebug() << "overviewview: " << val;
}

jsulm

@hobbyProgrammer You made sure overviewView::valAdded was called?
Do you really have only one overviewView instance (I'm asking because this is a mistake people often do :-))?

Is ovView not nullptr here:

overviewView *ovView = qobject_cast<overviewView*>(ui->graphicsView);

?

hobbyProgrammer

@jsulm I added qDebug() << ovView
and it gave me this:

overviewView(0x1fef8160, name="graphicsView")

so it doesn't seem to be a nullptr.
Also I have only 1 ovView.

jsulm

@hobbyProgrammer Check what connect() returns.

hobbyProgrammer

@jsulm it returns true

jsulm

@hobbyProgrammer Do you actually have event loop running when you emit the signal?