Qt 5, get the mouse position in a screen

Question

First of all, I\'d like to mention that I found that related post How to get the mouse position on the screen in Qt? but it \"just didn\'t work\" for me. I made some tests,

Answer 1

To figure out on which screen you are, you can iterate throught QGuiApplication::screens() and check whether the cursor fits in the geometry of the screen.

Here is a more complex example to compute the native cursor position (note the additional work needed to work with High DPI screens):

QPoint getNativeCursorPosition()
{
    QPoint pos = cursorPosToNative(QCursor::pos());

    // Cursor positions from Qt are calculated in a strange way, the offset to
    // the origin of the current screen is in device-independent pixels while
    // the origin itself is native!

    for (QScreen *screen : QGuiApplication::screens()) {
        QRect screenRect = screen->geometry();
        if (screenRect.contains(pos)) {
            QPoint origin = screenRect.topLeft();
            return origin + (pos - origin) * screen->devicePixelRatio();
        }
    }

    // should not happen, but try to find a good fallback.
    return pos * qApp->devicePixelRatio();
}