I have an "export" xPage that will be used to create an Excel spreadsheet of just the selected documents from a view.  This works fine when I'm exporting the entire view, but now I have a requirement to just export selected documents.  I'm getting a completely blank spreadsheet.  I am getting the correct docIDs - I've already confirmed that with a computed field.  Any ideas why this doesn't work?  This code is in the afterRenderResponse of the xPage:

var exCon = facesContext.getExternalContext();

var writer = facesContext.getResponseWriter();

var response = exCon.getResponse();

docIDArray=sessionScope.get(selectedDocs);

var output:string="";

response.setContentType("application/vnd.ms-excel");

response.setHeader("Cache-Control","no-cache");

writer.write("<table>");

writer.write("<thead><tr>");

writer.write("<td><b>Status</b></td>");

writer.write("<td><b>Group</b></td>");

writer.write("</tr></thead>");

for(i=0; i < docIDArray.length ; i++){

  var docID=docIDArray[i];

  var doc=database.getDocumentByID(docID);

  if(doc != null){

    output += "<tr>";

    output += "<td>" + doc.getItemValueString("Status")+"</td>";

    output += "<td>" + doc.getItemValueString("Group")+"</td>";

    output += "</tr>";

}};

writer.write(output);

writer.write("</table>");

writer.endDocument();