Detecting the removal of a screen and modifying the app accordingly.

[MrCrackPotBuilder]

So far I have an application that counts how many screens are available.

QDesktopWidget *widget = QApplication::desktop();
qDebug() << 'Number of screens:' << widget->screenCount();

if (widget->screenCount() > 1) {
    leftScreen.show();
    rightScreen.show();
    singleScreen.close();
} else if (widget->screenCount() == 1){
    leftScreen.close();
    rightScreen.close();
    singleScreen.show();
}

This will debug how many screens to console and if more than 1 the 2 screens are shown and if only one then the one screen.

If i remove a screen though nothing else changes but if i close the application and then open it again the single ui will display.

QGuiApplication has a member called screenRemoved but im struggling to figure out how to incorporate that into my application.

Later i will tell each screen to go to its set place but that is pretty straight forward.

[sierdzio]

You can listen to screenCountChanged() signal to know when the count changes.

[MrCrackPotBuilder]

Thanks although what arguments do i put in? The docs don't really mention much.

Its also saying the same as before so I.m definitely going to have to use the QGuiApplication but how that i cant figure out... Yet

[mrjj]

@MrCrackPotBuilder
Hi
Its a signal so you would connect it up to your own slot and Qt will then call
this slot when screen count changes.

[MrCrackPotBuilder]

ah then im going to need to make a new header and source file becuase its all being done in main.cpp

im taking a wild guess but inside my main i could do

QQuiApplicationt::connect(&screenRemoved, &displayChange::displayChange);

[J.Hilk]

@MrCrackPotBuilder said in Detecting the removal of a screen and modifying the app accordingly.:

Its also saying the same as before so I.m definitely going to have to use the QGuiApplication but how that i cant figure out... Yet

you #include <QGuiApplication> in your class that than allows you access to the (unique) application instance pointer qApp than you can use that to update your Layout.

QObject::connect(qApp, &QGuiApplication::screenCountChanged,  this,      &myClass::screenCountSlot);