My QProgressDialog is being shown unintentionally

jmguerra

After updating to Qt5.14 (c++), all my QProgressDialog are being shown at the start of the program, as if there was a signal being emitted to show all of them. Even if I set the default state to hidden (myDialog->setHidden(true)), they still come up. It only happens to QProgressDialog objects and not for other widgets.

Does someone know where could this unwanted behaviour come from?

    m_exportDialog = new QProgressDialog(parent);
    m_exportDialog->setWindowModality(Qt::NonModal);
    m_exportDialog->setWindowFlags(Qt::Tool | Qt::WindowTitleHint | Qt::CustomizeWindowHint );
    m_exportDialog->setLabelText(tr("Exporting data to USB drive..."));
    m_exportDialog->setCancelButton(nullptr);
    m_exportDialog->setRange(0, 0);
    m_exportDialog->setMinimumDuration(0);
    m_exportDialog->setFixedSize(600, 120);
    m_exportDialog->setHidden(true);

After that, no m_exportDialog->show() is being called, but the dialog still comes up.

Christian Ehrlicher

Ah, that's coming from the fact that a QProgressDialog is only shown when the duration is long enough to avoid flicker. Therefore a showTimer is started which now kills you.
Then the easiest way is to create the dialog really only when you need it instead during program start.

mrjj

Hi
And it shows itself as a floating window?

jmguerra

@mrjj yes 🤔

mrjj

Hi
So when shown, you can move it around ?
I was for a moment wondering if it got embedded but
it should be clear if its floating or inside other form.

jmguerra

@mrjj
Yes! I can move them (several progressDialogs) around. (Sorry for deleting the reply, I thought it was duplicated).

I can also force m_exportDialog->hide() after the program is initialized, but I think that's just a hack and not a solution because I see them while my app is launching.

Christian Ehrlicher

Derive from QProgressDialog, overwrite showEvent(), set a breakpoint there and see from where it is called.

jmguerra

@Christian-Ehrlicher I inherited from QProgressDialog and set a breaking point at showEvent, it stops after the following call stack:

GammaBot.exe!se::TestDialog::showEvent(QShowEvent * __formal) Line 48 C++
Qt5Widgetsd.dll!QWidget::event() + 3796 bytes Unknown
Qt5Widgetsd.dll!QApplicationPrivate::notify_helper() + 415 bytes Unknown
Qt5Widgetsd.dll!00007ffed0f602a8() Unknown
common.dll!se::LoggingApplication::notify(QObject * receiver, QEvent * event) Line 18 C++
Qt5Cored.dll!QCoreApplication::notifyInternal2() + 288 bytes Unknown
Qt5Cored.dll!QCoreApplication::sendEvent() + 66 bytes Unknown
Qt5Widgetsd.dll!QWidgetPrivate::show_helper() + 501 bytes Unknown
Qt5Widgetsd.dll!QWidgetPrivate::setVisible() + 881 bytes Unknown
Qt5Widgetsd.dll!QWidget::setVisible() + 136 bytes Unknown
Qt5Widgetsd.dll!QDialog::setVisible() + 393 bytes Unknown
Qt5Widgetsd.dll!QWidget::show() + 139 bytes Unknown
Qt5Widgetsd.dll!QProgressDialog::forceShow() + 86 bytes Unknown
Qt5Widgetsd.dll!QProgressDialog::qt_static_metacall() + 431 bytes Unknown
Qt5Cored.dll!00007ffecf7255a3() Unknown
Qt5Cored.dll!QMetaObject::activate() + 103 bytes Unknown
Qt5Cored.dll!QTimer::timeout() + 62 bytes Unknown
Qt5Cored.dll!QTimer::timerEvent() + 74 bytes Unknown
Qt5Cored.dll!QObject::event() + 147 bytes Unknown
Qt5Widgetsd.dll!QApplicationPrivate::notify_helper() + 415 bytes Unknown
Qt5Widgetsd.dll!QApplication::notify() + 1751 bytes Unknown
common.dll!se::LoggingApplication::notify(QObject * receiver, QEvent * event) Line 18 C++
Qt5Cored.dll!QCoreApplication::notifyInternal2() + 288 bytes Unknown
Qt5Cored.dll!QCoreApplication::sendEvent() + 66 bytes Unknown
Qt5Cored.dll!QEventDispatcherWin32Private::sendTimerEvent() + 148 bytes Unknown
Qt5Cored.dll!00007ffecf7847cb() Unknown
user32.dll!CallWindowProcW() + 1217 bytes Unknown
user32.dll!DispatchMessageW() + 467 bytes Unknown
Qt5Cored.dll!QEventDispatcherWin32::processEvents() + 1439 bytes Unknown
qwindowsd.dll!00007ffecb936784() Unknown
Qt5Cored.dll!QEventLoop::processEvents() + 109 bytes Unknown
Qt5Cored.dll!QEventLoop::exec() + 415 bytes Unknown
Qt5Cored.dll!QCoreApplication::exec() + 362 bytes Unknown
Qt5Guid.dll!QGuiApplication::exec() + 24 bytes Unknown
Qt5Widgetsd.dll!QApplication::exec() + 10 bytes Unknown

It seems like forceShow() is being trigered by some random timer.

Christian Ehrlicher

Ah, that's coming from the fact that a QProgressDialog is only shown when the duration is long enough to avoid flicker. Therefore a showTimer is started which now kills you.
Then the easiest way is to create the dialog really only when you need it instead during program start.

jmguerra

@Christian-Ehrlicher I didn't think about that alternative, is it an appropriate practice to create widgets after start?

Christian Ehrlicher

@jmguerra said in My QProgressDialog is being shown unintentionally:

is it an appropriate practice to create widgets after start?

No, I don't see why someone would first create all widgets during start. It just takes time for no good reason.

jsulm

This post is deleted!

AMaryBell

This post is deleted!