Opening windows on different x screens

[Shades]

We have an application that opens two windows. We want them to open on two different X screens. We don't use Twinview or xinerama. The gfxcard is Nvidia. The code we use is:

ourWindow->setGeometry(QApplication::desktop()->availableGeometry(1));

ourWindow->setGeometry(QApplication::desktop()->availableGeometry(1));

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But when we check the screen number afterwards:

cout << "Screennumber: " << QApplication::desktop()->screenNumber(ourWindow.get()) << endl;

cout << "Screennumber: " << QApplication::desktop()->screenNumber(ourWindow.get()) << endl;

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It gives us screennumber 0. All the screens also opens on the same desktop. Is something buggy or are we doing it wrong?

cout << "Number of screens: " << QApplication::desktop()->numScreens() << endl;

cout << "Number of screens: " << QApplication::desktop()->numScreens() << endl;

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gives us Number of screens: 2, so Qt see our two screens.

/regards
Erik