// JavaScript Document
//document.getElementById("radio3").checked=true

// holds an instance of XMLHttpRequest 

var xmlHttp = createXmlHttpRequestObject();

function createButton(value){
  // only continue if xmlHttp isn't void 
  var value=value;
  if (xmlHttp) 
  { 
    // try to connect to the server 
    try 
    { 
	// call the server page to execute the server side operation 
  xmlHttp.open("GET", "orderButton.php?value="+value, true); 
  xmlHttp.onreadystatechange = handleRequestStateChange; 
  xmlHttp.send(null);
	}
	
	// display the error in case of failure 
    catch (e) 
    { 
      alert("Can't connect to server:\n" + e.toString()); 
    } 
  }
}

// creates an XMLHttpRequest instance 
function createXmlHttpRequestObject()  
{ 
  // will store the reference to the XMLHttpRequest object 
  var xmlHttp; 
  // this should work for all browsers except IE6 and older 
  try 
  { 
    // try to create XMLHttpRequest object 
    xmlHttp = new XMLHttpRequest(); 
  } 
  catch(e) 
  { 
    // assume IE6 or older 
    var XmlHttpVersions = new Array('MSXML2.XMLHTTP.6.0', 
                                    'MSXML2.XMLHTTP.5.0', 
                                    'MSXML2.XMLHTTP.4.0', 
                                    'MSXML2.XMLHTTP.3.0', 
                                    'MSXML2.XMLHTTP', 
                                    'Microsoft.XMLHTTP'); 
    // try every prog id until one works 
    for (var i=0; i<XmlHttpVersions.length && !xmlHttp; i++)  
    { 
      try  
      {  
        // try to create XMLHttpRequest object 
        xmlHttp = new ActiveXObject(XmlHttpVersions[i]); 
      }  
      catch (e) {} // ignore potential error 
    } 
  } 
  // return the created object or display an error message 
  if (!xmlHttp) 
    alert("Error creating the XMLHttpRequest object."); 
  else  
    return xmlHttp; 
}


// function executed when the state of the request changes 
function handleRequestStateChange()  
{ 
// obtain a reference to the <div> element on the page 
  progress = document.getElementById("progressBar"); 
  myDiv = document.getElementById("orderButton"); 
  // display the status of the request
  if (xmlHttp.readyState == 1) 
  { 
    document.getElementById("progressBar").style.visibility="visible";
    progress.innerHTML = "<img src=images/Progressbar2.gif> <br/>"; 
  } 
 else if (xmlHttp.readyState == 2) 
  { 
	document.getElementById("progressBar").style.visibility="hidden";
  } /*
  else if (xmlHttp.readyState == 3) 
  { 
    myDiv.innerHTML += "Request status: 3 (interactive) <br/>"; 
  } */
  
  // continue if the process is completed 
  else if (xmlHttp.readyState == 4)  
  { 
    // continue only if HTTP status is "OK" 
    if (xmlHttp.status == 200)  
    { 
      try 
      { 
        // retrieve the response 
        response = xmlHttp.responseText; 
        // do something with the response  
        myDiv.innerHTML = response; 
      } 
      catch(e) 
      { 
        // display error message 
        alert("Error reading the response: " + e.toString()); 
      } 
    }  
    else 
    { 
      // display status message 
      alert("There was a problem retrieving the data:\n" +  
            xmlHttp.statusText); 
    } 
  } 
}