Is there an event on QWidget to detect when a windows exits fullscreen (ie by calling showNormal)?

Michael A. Leonetti

On MacOS my program uses showFullscreen to go into fullscreen mode and after that I want to hide it directly after it exits fullscreen mode. If I call showNormal() or setWidowState( windowState()&~Qt::WindowFullScreen ) and then hide() directly after, the window does exit full screen but doesn't hide.

Is there a way to detect when fullscreen is done being exited so I can hide the window? Or even hide the window straightaway from fullscreen?

SGaist

Hi,

In the documentation of QWidget::setWindowState, it's mentioned that you can use QEvent::WindowStateChange.

Excerpt:

When the window state changes, the widget receives a changeEvent() of type QEvent::WindowStateChange.

Michael A. Leonetti

Hello! Thank you for responding.

I should have mentioned that the documentation is correct in this regard. I have this in my code:

void Video::changeEvent( QEvent *event )
		{
			if( event->type()==QEvent::WindowStateChange and !(windowState()&Qt::WindowFullScreen) )
			{
				LOG_TRACE( logger() ) << "Hiding window.";

				hide();
			}
		}

But it gets called too early and the window doesn't hide. I'm assuming because MacOS is still animating taking the window off of fullscreen mode?

I can use a timer with an arbitrary amount of seconds (like 5) and it completes the hide. I was just wondering if there was a more streamlined way.

kshegunov

@Michael-A.-Leonetti said in Is there an event on QWidget to detect when a windows exits fullscreen (ie by calling showNormal)?:

I can use a timer with an arbitrary amount of seconds (like 5) and it completes the hide. I was just wondering if there was a more streamlined way.

Perhaps something like this:

QMetaObject::invokeMethod(this, &QWidget::hide, Qt::QueuedConnection);

instead of hide().

Michael A. Leonetti

Thank you for your suggestion. I've changed the code to:

	void Video::changeEvent( QEvent *event )
	{
		if( event->type()==QEvent::WindowStateChange and !(windowState()&Qt::WindowFullScreen) )
		{
			LOG_TRACE( logger() ) << "Hiding window.";

			//hide();

			QMetaObject::invokeMethod( this, &QWidget::hide, Qt::QueuedConnection );
		}
	}

And unfortunately it doesn't hide it still.

SGaist

Did you check whether you get other events between the moment you get this event and the end of the animation ?

Michael A. Leonetti

If I put a

LOG_TRACE( logger() ) << __PRETTY_FUNCTION__ << ": " << event->type();

At the beginning of the function I get exactly 1 event at the beginning of the animation:

2019-03-14, 17:31:55.977997: <trace> (0x000000011a3225c0) [GUI Video] virtual void xconnect::gui::Video::changeEvent(QEvent *): 105

What's funny is that if I invoke hide() the child widgets all disappear, but the main widget does not disappear. If I call hide on a timer the main widget will disappear also.

So this will work:

// We are normal
					setWindowState( windowState()& (~Qt::WindowFullScreen) );

					// Queue a timer on hiding
					QTimer::singleShot( 1000, this, &Video::hide );

I'm just not sure how portable it is on all macs but it will dismiss the window from full screen and the window will hide.

SGaist

What version of macOS are you running ?

Michael A. Leonetti

Now 10.14.1 Mojave as of yesterday evening. Was 10.13 High Sierra when I first started getting this error.

SGaist

Can you share a minimal compilable exemple that shows this behaviour ?