How to quit an eventLoop connect to a signal containing arguments?

[Ylvy]

I'm getting this error in the evenLoop.quit() line:

E1086 the object has type qualifiers that are not compatible with the member function "QEventLoop::quit"

QEventLoop eventLoop;

connect(msgBox, &MsgBox::signalCancel, &eventLoop, [=] (QString text)
{
        qDebug() << text;
        eventLoop.quit();
});

eventLoop.exec();

What the proper way to quit the loop in this case?

[JonB]

@Ylvy said in How to quit an eventLoop connect to a signal containing arguments?:

eventLoop.quit();

I can't test, but don't you mean this->quit() or just quit() since &eventLoop is the this for the slot lambda?

If not that, does it make any difference here if you use [&] instead of [=]?

[Christian Ehrlicher]

Apart from the fact that I don't see a need for a local eventloop - how is you signalCancel defined?

[Ylvy]

@Christian-Ehrlicher
The event loop is to wait the click in one of the MsgBox buttons.

QT_BEGIN_NAMESPACE
namespace Ui { class MsgBox; };
QT_END_NAMESPACE

class MsgBox : public QWidget
{
    Q_OBJECT
public:
    Ui::MsgBox* m_ui;
    MsgBox(QWidget* parent)
    void cancel();
signals:
    void signalCancel(QString text);
};

MsgBox::MsgBox(QWidget* parent) : QWidget(parent)
    , m_ui(new Ui::MsgBox())
{
	m_ui->setupUi(this);
	connect(m_ui->cancel, &QPushButton::clicked, this, &MsgBox::cancel);
}

void MsgBox::cancel()
{
	emit signalCancel("test 123");
}

[JonB]

@Ylvy said in How to quit an eventLoop connect to a signal containing arguments?:

eventLoop.quit();

I can't test, but don't you mean this->quit() or just quit() since &eventLoop is the this for the slot lambda?

If not that, does it make any difference here if you use [&] instead of [=]?

[Christian Ehrlicher]

@JonB said in How to quit an eventLoop connect to a signal containing arguments?:

If not that, does it make any difference here if you use [&] instead of [=]?

You're correct - QEventLoop is an QObject and therefore can't be copied.

[Ylvy]

@JonB with [&] it work correctly, thank you all!

[Christian Ehrlicher]

@Ylvy said in How to quit an eventLoop connect to a signal containing arguments?:

m_ui

this is leaking.

Still don't understand why you are blocking the execution with a local eventloop.

[Ylvy]

@Christian-Ehrlicher what is leaking? the ui i destructed in the class destructor?

Still don't understand why you are blocking the execution with a local eventloop.

The execution is blocked until one of the buttons of the class is clicked, how else i would block it until the click?

[JonB]

@Ylvy
It is not clear why you want to block till a button is clicked from a QWidget.

In any case is QDialog and exec(), a modal dialog, not what you want here?