I keep getting the error
"undefined is null or not an object". In FireFox I get
"xmlhttp.responseXML has no properties".
The output of my JSP is just something like this:
<option>2005</option>
<option>2006</option>
....in Firefox, if I run the JSP page... the browser tells:
XML Parsing Error: junk after document element
Location: http://localhost/p1/searchAvailableYears.jsp?pType=A
Line Number 2, Column 1:<option>2005</option>
^
....And I am not sure if THAT is the problem..... but how do I solve it?
Below is the part of the code of the main HTML/JSP page where the <select> is:
Code:
<select name="pType" onchange="handleOnChange(this)">
<option>---</option>
<%
String allDir[] = {"A", "B", "C"}; //dirs con los que se trabajará
for(int i=0; i<3; i++)
{
File dir = new File("C:/apache-tomcat-6.0.10/webapps/ROOT/p1/db/" + allDir[i] ); //(fenomenos A, B, C)
if (dir.exists() && dir.isDirectory())
{
%>
<option><%=allDir[i]%></option>
<%
} //if
} //for
%>
</select>
</td></tr>
<td><strong>Year</strong></td>
<td>
<select name="year" onchange="handleOnChange(this)">
<option>---</option>
</select>
------------
And below is the javascript that handles the Ajax calls:
Code:
<script language="javascript" type="text/javascript">
//vars globales
var txtPType;
var txtYear;
var txtDay;
var txtTime1;
var xmlhttp;
var laLista;
//-------------------------------------------------------------------------->>>>>>>>
function block(lista)
{
lista.disabled=true;
lista.style.backgroundColor='#CCCCCC';
}
//-------------------------------------------------------------------------->>>>>>>>
function unblock(lista)
{
lista.disabled=false;
lista.style.backgroundColor='';
}
//-------------------------------------------------------------------------->>>>>>>>
function removeItems(lista)
{
for(var i = 0; i < lista.length; i++)
{ lista.remove(i); }
}
//-------------------------------------------------------------------------->>>>>>>>
function handleOnChange(ddl)
{
//index y texto del item seleccionado
var ddlIndex = ddl.selectedIndex;
var ddlText = ddl[ddlIndex].text;
var frmSelect = document.forms["form1"];
var frmSelectElem = frmSelect.elements;
if(ddl.name="pType")
{
txtYear = "";
txtDay = "";
txtTime = "";
unblock(document.form1.year);
block(document.form1.day);
block(document.form1.time1);
laProxLista = frmSelectElem["year"];
if (ddl.options[ddl.selectedIndex].text != "---")
{
txtPType = ddl.options[ddl.selectedIndex].text;
}
}
else if(ddl.name="year")
{
txtDay="";
txtTime="";
unblock(document.form1.day);
block(document.form1.time1);
laProxLista = frmSelectElem["day"];
if (ddl.options[lista.selectedIndex].text != "---")
{
txtYear = ddl.options[lista.selectedIndex].text;
}
}
else if(ddl.name="day")
{ txtTime = "";
unblock(document.form1.time1);
laProxLista = frmSelectElem["time1"];
if (ddl.options[ddl.selectedIndex].text != "---")
{
txtDay = ddl.options[ddl.selectedIndex].text;
}
}
else //time1
{
laProxLista = null;
if (ddl.options[ddl.selectedIndex].text != "---")
{
txtTime1 = ddl.options[ddl.selectedIndex].text;
}
}
if ( txtPType != "---")
{
xmlhttp = null
if (window.XMLHttpRequest){
xmlhttp = new XMLHttpRequest()
}
else if (window.ActiveXObject) {
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP")
}
if (xmlhttp != null)
{
if(ddl.name = "pType")
{
// Setting the JSP/Servlet url to get XmlData
url = "searchAvailableYears.jsp?pType=" + txtPType;
}
else if(ddl.name = "year")
{
url = "searchAvailableDOY.jsp?pType=" + txtPType + "&year=" + txtYear;
}
else(ddl.name = "day")
{
url = "searchAvailableTimes.jsp?pType=" + txtPType + "&year=" + txtYear + "&day=" + txtDay;
}
xmlhttp.onreadystatechange = handleHttpResponse;
xmlhttp.open("GET",url,true);
xmlhttp.send(null);
}
else{
alert("Your browser does not support XMLHTTP.")
} //else
} //if chosen
} //fucntion
//----------------------------
function verifyReadyState(obj){
if(obj.readyState == 4){
if(obj.status == 200){
return true;
}
else{
alert("Problem retrieving XML data")
}
}
}
//----------------------------------------------------
function handleHttpResponse()
{
if(verifyReadyState(xmlhttp) == true)
{
// Building a DOM parser from Response Object
var response = xmlhttp.responseXML.responseText;
alert(response);
//First, remove the actual items
removeItems(laProxLista);
var _x = response.getElementsByTagName("option");
var txt;
var newOption;
for(var i = 0; i < _x.length; i++)
{
newOption = document.createElement("OPTION");
txt = _x[i].text;
//newOption.text = txt[0].firstChild.data;
newOption.text = txt
laProxList.add(newOption);
}
} //if
else
{
alert(_x);
}
}//function
//------------------------------------------------
function verifyReadyState(obj){
if(obj.readyState == 4){
if(obj.status == 200){
return true
}
else{
alert("Problem retrieving XML data")
}
}
}
</script>
-------------------
And an example of one of my JSP codes:
Code:
<%@ page contentType="text/html" %><%@page import="java.io.*, javax.servlet.*, javax.servlet.http.*, java.lang.*, java.util.*"%>
<%
String pType = request.getParameter("pType");
response.setContentType("text/xml");
//response.setHeader("Cache-Control", "no-cache");
PrintWriter _out = response.getWriter();
File dir = new File("C:/apache-tomcat-6.0.10/webapps/ROOT/p1/db/" + pType);
String[] allFilesInDir = dir.list();
ArrayList years = new ArrayList();
String option;
try
{
for(int i=0; i < allFilesInDir.length; i++)
{
if (years.contains(allFilesInDir[i].substring(1,5)) == false)
{
years.add(allFilesInDir[i].substring(1,5));
option = "<option>" + years.get(i) + "</option>";
_out.println(option);
} //if
} //for
} //try
catch(NullPointerException e)
{
//_out.println("<option>Data not available</option>");
}
%>
I've been working with this thing for more than a week and I really need help because I am the only
clown here who decided to try it...so you may understand...
-----------------------------------------------------
And another question... I tried to do it without Ajax, but I did not know how the heck I can tell the "response" that those
<option>2005</option>
<option>2006</option>
...goes to ....
<select name="pType" onchange="handleOnChange(this)">
<!--- HERE! -->
</select>
I tried with...
Code:
function clickedOnPType(lista)
{
if (lista.options[lista.selectedIndex].text != "---")
{
txtPType = lista.options[lista.selectedIndex].text;
}
txtYear = "";
txtDay = "";
txtTime = "";
unblock(document.form1.year);
block(document.form1.day);
block(document.form1.time1);
document.form1.action = "searchAvailableYears.jsp?pType=" + txtPType;
document.form1.submit();
}
.... but I only get a plain page with ....
2005 2006 2007
......when I saw the source of the page it gives....
<option>2005</option>
<option>2006</option>
<option>2007</option>
Any help is appreciated!
--MMS--
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ajax: resonseXML without properties, undefined is null or not an object
