show table header in filebrowser always on top when files are selected

files/css/files.css

@@ -39,6 +39,8 @@ table td.filename a, table td.login, table td.logout, table td.download, table t
 table td.filename .nametext, .modified { float:left; padding:.3em 0; }
 table td.filename .nametext { width:60%; }
 table td.filename form { float:left; font-size:.85em; }
+table thead.fixed tr{position:fixed; top:6.4em;z-index:100;}
+table thead.fixed {height:2em}
 #fileList tr input[type=checkbox] { display:none; float:left; margin:.7em 0 0 1em; /* bigger clickable area doesn’t work in FF width:2.8em; height:2.4em;*/ }
 #fileList tr input[type=checkbox]:checked, #fileList tr:hover input[type=checkbox] { display:inline; }
 #fileList tr.selected td.filename a, #fileList tr:hover td.filename a { background-image:none !important }

files/js/files.js

@@ -344,7 +344,18 @@ function procesSelection(){
 		$('#modified').text('Modified');
 		$('th').removeClass('multiselect');
 		$('.selectedActions').hide();
+		$('thead').removeClass('fixed');
+		$('#headerName').css('width','auto');
+		$('#headerSize').css('width','auto');
+		$('#headerDate').css('width','auto');
+		$('table').css('padding-top','0');
 	}else{
+		var width={name:$('#headerName').css('width'),size:$('#headerSize').css('width'),date:$('#headerDate').css('width')};
+		$('thead').addClass('fixed');
+		$('#headerName').css('width',width.name);
+		$('#headerSize').css('width',width.size);
+		$('#headerDate').css('width',width.date);
+		$('table').css('padding-top','2em');
 		$('.selectedActions').show();
 		var totalSize=0;
 		for(var i=0;i<selectedFiles.length;i++){