QWIDGET: CANNOT CREATE A QWIDGET WITHOUT QAPPLICATION - Message Box

[Mathan M]

Hi,

I used the Qmessage Box in the project created Qt Quick C++ template.
When I try to show an message box, I encounter the following error:

QWIDGET: CANNOT CREATE A QWIDGET WITHOUT QAPPLICATION

Code:

void QtCPPSearchVOne::funsearchMap()
{
QString obj;
obj = QString::QString("Event Fired");

QMessageBox msgbox;
msgbox.setText(obj );
msgbox.exec();
}

Thanks in advance.

Mathan

[SGaist]

Hi,

Go to your main.cpp You'll see there that a QGuiApplication is created. Replace it by QApplication.

As to why: there's no need for widget support when writing a Qt Quick application unless you make use of classes like QMessageBox.

[JANG SOONMYUN]

@SGaist said in QWIDGET: CANNOT CREATE A QWIDGET WITHOUT QAPPLICATION - Message Box:

writing

Thank you so much! I had a problem with opencv::imshow. And this solution works well.