// center align and strip a popup window
// <a href="pop_mediafiles.php" target="getphoto" onclick="showPopup(this.href, this.target, 540, 280, 1, 1, 0);">
function showPopup(url, name, width, height, scroll, resizable, statusbar, screenpos) {
	var Xwin = width;
	var Ywin = height;
	var Xsize = screen.availWidth;
	var Ysize = screen.availHeight;
	var Xpos = 0;
	var Ypos = 0;
	switch(screenpos) {
		case "topleft":
			Xpos = 0;
			Ypos = 0;
			break;
		case "topright":
			Xpos = Xsize - width;
			Ypos = 0;
			break;
		case "bottomleft":
			Xpos = 0;
			Ypos = Ysize - height;
			break;
		case "bottomright":
			Xpos = Xsize - width;
			Ypos = Ysize - height;
			break;
		default:
			Xpos = (Xsize - width) / 2;
			Ypos = (Ysize - height) / 2;
			break;
	}
	var popwin;
	var opts = "status=" + statusbar + ",resizable=" + resizable + ",scrollbars=" + scroll + ",height=" + Ywin + ",width=" + Xwin + ",left=" + Xpos + ",top=" + Ypos;
	popwin = window.open(url, name, opts);
	popwin.focus();
}

// toggle all elements to closed and open just one
// send in name of elements, and array of all elements to close
function togglefields(fieldname, myfields){
	for (i = 0; i < myfields.length; i++){
		document.getElementById(myfields[i]).className = 'hiddenEl';
	}
	document.getElementById(fieldname).className = 'shownEl';			
}