With the code below, the app doesn't fill the entire screen when it comes back from background to foreground. ( qtbug81027_ipad_screenshot.png )

main.cpp

QQuickView view;
view.setResizeMode(QQuickView::SizeRootObjectToView);
...

main.qml

Rectangle {
    id: app
    visible: true

    property var i : Screen.width >= 0 ? 1 : 1

    width: 640 * i
    height: 480 * i
 ...
}

The same behavior occurs at least with Screen.height and Screen.logicalPixelDensity.

How to reproduce:
1. Run the sample code (qtbug81027.zip) on iPad
2. Put the app to the background (by pressing home button)
3. Bring the app to foreground

Result :
The app does not fill the entire screen (qtbug81027_ipad_screenshot.png)

Workaround ?
Modify var to some other type e.g. int or real enables the app to fill the entire screen when it returns to foreground.