Works:
    Row {
        spacing: 2
        Rectangle{
            color: "blue";
            width: 80;
            height:80;
        }
        Rectangle{
            color: "green";
            width: 80;
            height:80;
        }
    }


does not work:
    Row {
        spacing: 2
        Rectangle{
            color: "blue";
            width: Theme.iconSizeLauncher.width;
            height:80;
        }
        Rectangle{
            color: "green";
            width: Theme.iconSizeLauncher.width;
            height:80;
        }
    }