function windowOpener(windowHeight, windowWidth, windowName, windowUri)
{
    var centerWidth = (window.screen.width - windowWidth) / 2;
    var centerHeight = (window.screen.height - windowHeight) / 2;

    newWindow = window.open(windowUri, windowName, 'scrollbars=1,resizable=1,width=' + windowWidth + 
        ',height=' + windowHeight + 
        ',left=' + centerWidth + 
        ',top=' + centerHeight);

    newWindow.focus();
}






var pagina=null;
function apriPopup(url,w,h){
	x=screen.width/2-w/2;
	y=screen.height/2-h/2;
	if (pagina != null)
		pagina.close();
	pagina=window.open(url,"","fullscreen=no,status=no,toolbar=no,scrollbars=yes,width="+w+",height="+h+",top="+y+",left="+x);
}