Using JSP parameters as input in a JavaScript function

Question

hey
I have a JavaScript function, which I call with JSP parameters.
The function call looks similar to:
<button onclick="myFunction(<%= jspParameter%>);"> </button>
However, this JavaScript function is called from a jsp page, which is asynchronously refreshed upon a click of the button.
The problem is that the JavaScript function does NOT function when I click the button for the first time (or maybe it functions, but with the old value of the jspParameter).
Only after the second click it starts taking the jspParameter.
Can you please tell me how to properly get the jspParameter as input in my case....
thank you

Answer 1

I'm sorry, you're right - I didn't give enough details.
My whole page consists of several jsp-s.
The jsp, from which I call the JavaScript function is just one part of the whole page. I'll call it partToBeChanged.jsp.
When I press the button, the partToBeChanged.jsp should refresh asynchronously and call the JavaScript function using the new jsp parameter as input.
To be more precise, here is roughly how myFunction looks like (JavaScript):
function myFunction(url, jspParam) {
     var XMLHttpRequestObject = false;
     if (window.XMLHttpRequest) {
          XMLHttpRequestObject = new XMLHttpRequest();
     } else if (window.ActiveXObject) {
          XMLHttpRequestObject = new ActiveXObject("Microsoft.XMLHTTP");
     if (XMLHttpRequestObject) {
          XMLHttpRequestObject.open("GET", myServlet + url, true);
          XMLHttpRequestObject.onreadystatechange = function() {
               if (XMLHttpRequestObject.readyState == 4 && XMLHttpRequestObject.status == 200) {
                    //plug server response in the target place.
                    //The target is an id of a division, which holds the partToBeChanged.jsp page
                    //The server itself uses RequestDispatcher to direct the response to the partToBeChanged.jsp     
                    //NOTE: partToBeChanged is only a part of the whole HTML page, which is refreshed dynamically               
                    document.getElementById('target').innerHTML = XMLHttpRequestObject.responseText;
                    //changes the content of a div, which is IN ANOTHER .jsp fragment (different than partToBeChanged.jsp)
                    y = document.getElementById("div_to_change");
                    y.innerHTML = jspParam;
          XMLHttpRequestObject.send("");
}the jspParam is a java object, initialized in the servlet and used in partToBeChanged.jsp
To summarize: the servlet dispatches the response to the partToBeChanged.jsp page, which uses the jspParam as input for myFunction, and myFunction tries to change the content of the "target" div accorting to the jspParam. However it changes as expected only after the second button click.
Thanks a lot for any help....