iterate doubt

[Pradeep Adibatla]

I have an iterator which should iterate an ArrayList present in a session as...

<s:iterator value="#session.cityList" status="element">
<option><s:property value="???"/></option>
</s:iterator>

cityList is an ArrayList containing a few city names...

what should be the 'value' of "s:property" in the above to display all cities ??

[David Newton]

If it's an array of strings, you don't need to have *anything*--the property tag will display the top-most value stack value by default. If the cities are an object, the property tag's value attribute should be the name of the city property you want to display.

[Pradeep Adibatla]

It is an Arrayist of objects like...

say Australia,
sydney,hobart,Adelaide...

so now what would property take as I have put hem in a session and iterate?

If the cities are an object, the property tag's value attribute should be the name of the city property you want to display.

like this?

 <s:iterator value="#session.cityList" status="element"> 
<option><s:property value="cityList[#element.index]"/></option> 
</s:iterator> 
   

this doesn't work !!!

[David Newton]

Pradeep Adibatla wrote:It is an Arrayist of objects like... say Australia,sydney,hobart,Adelaide...

That tells me nothing about what kind of objects they are. Are they strings or not?

like this?

 <s:iterator value="#session.cityList" status="element"> 
<option><s:property value="cityList[#element.index]"/></option> 
</s:iterator> 

this doesn't work !!!

Correct, it doesn't, because you're using random expressions to try to get it to work, instead of doing what I told you to.

If the objects in the list are strings you don't *need* a "value" attribute in your property tag. If they're objects *containing* a string with the city name, then the "value" attribute should be the name of the object property containing the city's name.

[Pradeep Adibatla]

oops actully yes...
I declared the ArrayList like this

Arraylist cityList;

and ...

public Arrayist getCityList()
{
----
}

rather i think it should be...

ArrayList<City> citList

//getter

and then it should be...

 <s:property value=cityName />

[David Newton]

That's a lot of typos for such a small chunk of code :( Be careful! :)

[Pradeep Adibatla]

A small correction...

I had to use a hashmap but the problem persists somehow... I think i could manage with this without converting into ArrayList...

in action...

  
 LinkedHashMap<String, City> atrHMap1;
    
   
    public LinkedHashMap<String, City> getAtrHMap1()
    {
         System.out.println("in getATrHMap1() !!! ");

         return atrHMap1;
    }

session.setAttribute("atrHMap1",atrHMap1);


  

in jsp...

  
<s:iterator value="#session.atrHMap1" status="element">
 <option><s:property value="cityName"/></option>
</s:iterator> 
  

[David Newton]

Each object in a Map iteration is a MapEntry.

[Pradeep Adibatla]

Sorry, I couldn't comprehend that !!!

[David Newton]

If you're using <s:iterator> over a list, each object will be whatever class is in the list.

If you're using <s:iterator> over a Map, each object will be a Map.Entry.

[Pradeep Adibatla]

I thought this should be fine...

  
 <s:iterator value="atrHMap1.entrySet()" >
 <option><s:property value="%{value}"/></option>
 </s:iterator>  

Even this couldn't help...

 
 <s:iterator value="#session.atrHMap1.entrySet()" >
   

What else could be?

[David Newton]

Why get the entrySet? You're already iterating over a map, no?

So how is the map being filled? It'd be a *lot* quicker if you'd post everything related. It's clearly *something* you're doing wrong, and I'd rather just get it all dealt with at once rather than drag this out over days.

[Lucas Grijander]

first you have to create a List with all the cities you want to be displayed

second, in your jsp use just <s:iterator list="yourList"/>

this only work if the objects of your list are Strings

[David Newton]

Please make sure that posts help solve the problem--we're already past that point, not dealing with a list, not dealing with simple objects, and so on.

[Pradeep Adibatla]

<s:iterator value="#session.atrHMap1" >
                                                   <option><s:property value="%{value}"/></option>
                                                </s:iterator>

Even this is a error....

actually in the jsp there is a textfield and a button (OK) next to it followed by select box...

The user enters the Country name and click 'ok' button next to it.

Then I do an Ajax call sending the country name from javascript to action class...

Now on recieving the country name I get all the cities in that country using my 'City' class ( the code I wrote earlier) and I am populating in the select box...

Hope it's clear.Is it a wrong process to populate like that? kindly explain...

[David Newton]

You mean you're trying to populate a field on the page you're on by making an Ajax request?

If so, that most certainly won't work--the entire page you're on is rendered before anything else happens, that's just how web applications and JSP work--everything in the JSP happens on the server side. If you want to make an Ajax request and populate a field on the current page then you'd need to write the JavaScript to actually *do* that.

[Pradeep Adibatla]

Hey ! Thanks David.Now I know the reason...

The reason why I am making an Ajax request is to get the cities of the country selected! If there are alternative ways then I could be extremely happy to know!

If you want to make an Ajax request and populate a field on the current page then you'd need to write the JavaScript to actually *do* that.

What should be my next step.What should the javascript contain and what will be the way to populate it?

[David Newton]

Moving to HTML/JavaScript.

How to do it depends on the JavaScript framework you're using.

[Pradeep Adibatla]

I havn't used any framework .It's normal javascript.If somethng like Jquery or Dojo gives comfort,I would jump on them but I am desperate to finish this!!!

[Bear Bibeault]

Ajax is too big a subject to cover in a forum post. Heck, entire books are written on the subject. I suggest grabbing such a book or finding an online tutorial.

This article might be a good place to start.

[David Newton]

It'll be quicker to spend the 10-15 minutes necessary researching how to do this in a JavaScript library than to try to write and debug it by hand in a way that works across browsers.

[Pradeep Adibatla]

Yeah that how to do that part is void for me here.I am stuck...now what sould be done in JS?

[Bear Bibeault]

Bear Bibeault wrote:I suggest grabbing such a book or finding an online tutorial.

This article might be a good place to start.

If you want some code example, download the code for my jQuery in Action book and look in the code examples for chapter 8. The code, of course, assumes that you will use jQuery.

[Pradeep Adibatla]

ok! I have you book "Ajax in Action" and I have been trying to do this using Json...

I added json 0.32plugin jar...

added the mapping in struts.xml

I tried to convert that into Json array...

@JSON(name="jSONArray")
    public void getCityVals()
    {
        Country c=StorageBean.getCountryList().get(selectedCountry);    //this is passed from jsp via AJax call

         atrHMap1=c.getCityList();
        JSONArray jSONArray=new JSONArray();
         jSONArray.addAll((Collection) atrHMap1);

         for (int i = 0; i < jSONArray.size(); i++)
         {
           System.out.println("The items are :--> "+jSONArray.getString(i));
         }

I couldn't proceed further! Kindly provide some direction... I will work over your suggestion.

[David Newton]

(That's actually a different book.)

So now you need to take that JSON object, evaluate it in JavaScript, and use it to populate the select control.

[Pradeep Adibatla]

So now you need to take that JSON object, evaluate it in JavaScript, and use it to populate the select control.

I have searched for so many hours just couldn't progress anywhere?

Kindly tell me the way forward in terms of implementation....

[David Newton]

Five seconds on Google:

http://www.keyframesandcode.com/resources/javascript/jQuery/demos/populate-demo.html
http://remysharp.com/2007/01/20/auto-populating-select-boxes-using-jquery-ajax/

[Bear Bibeault]

I gave you a direct link to sample code. How much simpler can we make it?

[Pradeep Adibatla]

Thanks, David and Bear for those inputs.


Like in this example...

  

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
	"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
	<head>
		<meta http-equiv="Content-type" content="text/html; charset=utf-8">
		<title>Select test</title>
		<script type="text/javascript" src="/js/jquery.js"></script>
		<script type="text/javascript" charset="utf-8">
		$(function(){
			$("select#ctlJob").change(function(){
				$.getJSON("select.php",{id: $(this).val()}, function(j){
					var options = '';
					for (var i = 0; i < j.length; i++) {
						options += '<option value="' + j[i].optionValue + '">' + j[i].optionDisplay + '</option>';
					}
					$("#ctlPerson").html(options);
					$('#ctlPerson option:first').attr('selected', 'selected');
				})
			})			
		})
		</script>
	</head>
	<body>
		<select id="ctlJob">
			<option value="1">Manager</option>
			<option value="2">Lead Dev</option>
			<option value="3">Developer</option>
		</select>
		<select id="ctlPerson">
			<option value="1">Mark</option>
			<option value="2">Andy</option>
			<option value="3">Richard</option>
		</select>
	</body>
</html>
  

Looks superb,you could see a "select.php" there.

I was wondering how it would be in struts2 after having prepared the json object as shown in my code.I was talking about an example with struts2 which I thought I couldn't find out beacause jquery and php(atleast for the example) are unknown to me so still coming to terms with them .

I think i would need to change that "select.php" to "cityAction.action"

Now if I try to modify this according to my one,I could do this...

$(document).ready(function() {
            $(function() {
                $("select#countries").change(function() {
                    $.getJSON("cityAction.action?search=",{countryId: $(this).val(), ajax: 'true'}, function(j){
                    var options = '';
                        for (var i = 0; i < j.length; i++) {
                            options += '<option value="' + j[i].id + '">' + j[i].name + '</option>';
                        }
                        $("select#cities").html(options);
                    })
                })
            })
        });
    

But I don't know what the above one does...

I am fighting it out and will continue till I do so !!!

[Pradeep Adibatla]

After the Ajax call is made on selecting the country,I passed the country.Now,I have got this in my Action class...

  

@JSON(name="jSONArray")   
    public void getCityVals()   
    {   
        Country c=StorageBean.getCountryList().get(selectedCountry);    //this is passed from jsp via AJax call   
  
         atrHMap1=c.getCityList();   
        JSONArray jSONArray=new JSONArray();   
         jSONArray.addAll((Collection) atrHMap1);   
  
         for (int i = 0; i < jSONArray.size(); i++)   
         {   
           System.out.println("The items are :--> "+jSONArray.getString(i));   
         }  
    }
  

and this in jsp...

 

$(document).ready(function() {   
            $(function() {   
                $("select#countries").change(function() {   
                    $.getJSON("cityAction.action?search=",{countryId: $(this).val(), ajax: 'true'}, function(j){   
                    var options = '';   
                        for (var i = 0; i < j.length; i++) {   
                            options += '<option value="' + j[i].id + '">' + j[i].name + '</option>';   
                        }   
                        $("select#cities").html(options);   
                    })   
                })   
            })   
        });   
   

how should I proceed now?? what are the corrections?

[David Newton]

What doesn't work? ItDoesntWorkIsUseless.

[Pradeep Adibatla]

I added this for json in struts.xml...

 <package name="default1" extends="json-default" >
       <action name="Cules" class="CulesModelAction" >
          <result type="json">
             <param name="root">jsonData</param>
          </result>
       </action>
   </package>   

I also have the normal one...

  

<struts>
    <include file="struts-default.xml"/>
    <!-- Configuration for the default package. -->
    <package name="default" extends="struts-default">

   ...........................
   ............................
   
     <action name="cules" class="CulesModelAction">
            <result name="success">/jsp/tabtest.jsp</result>
            <result name="failure" >/jsp/cules.jsp</result>
        </action>
   </package>

  

Currently I am in cules.jsp...

I have a button 'tab' which takes me to tabtest.jsp which contains the 2 select boxes...



Now the problem is before I go to tabtest.jsp to select a country,when i click the button 'tab'(as said above) I get a window and I have no clue about this....

----------------------------------------------------------------------
opening rules.action

You have choosen to open rules.action

firefox is allowing you to open or save this file [Browse]
.......

OK Cancel buttons
---------------------------------------------------------------------

instead of being directed to tabtest.jsp as it was before adding that json mapping in struts.xml

I get this one...
-------------------------------------------
Current policy properties
thread.thread_num_limited: true
file.write.state: disabled
net.connect_ex_dom_list:
mmc.sess_cab_act.block_unsigned: false
mmc.sess_cab_act.action: validate
mmc.sess_pe_act.block_blacklisted: false
mmc.sess_pe_act.block_invalid: true
jscan.sess_applet_act.stub_out_blocked_applet: true
file.destructive.in_list:
jscan.sess_applet_act.block_all: false
file.write.in_list:
file.nondestructive.in_list:
window.num_limited: true
file.read.state: disabled
jscan.session.origin_uri: http://jsonplugin.googlecode.com/files/jsonplugin-0.32.jar
file.nondestructive.state: disabled
jscan.session.user_ipaddr: 10.81.82.131
net.connect_other: false
thread.thread_num_max: 8
file.destructive.ex_list:
file.nondestructive.ex_list:
file.write.ex_list:
jscan.sess_applet_act.sig_invalid: block
file.read.in_list:
mmc.sess_cab_act.block_invalid: true
jscan.session.policyname: TU1DIERlZmF1bHQgUG9saWN5
mmc.sess_pe_act.action: validate
thread.threadgroup_create: false
net.connect_in_dom_list:
net.bind_enable: false
jscan.sess_applet_act.sig_trusted: pass
jscan.session.user_name: 10.81.82.131
jscan.session.user_hostname:
file.read.ex_list:
jscan.sess_applet_act.sig_blacklisted: block
jscan.session.daemon_protocol: http
net.connect_src: true
jscan.sess_applet_act.unsigned: instrument
mmc.sess_pe_act.block_unsigned: false
file.destructive.state: disabled
mmc.sess_cab_act.block_blacklisted: true
window.num_max: 5


what could be it? If I remove that json mapping,I dont get this .Anything wrong with the mapping?I can't make it a single mapping,can I?

[Pradeep Adibatla]

Guys,Is the information insufficient? Experts kindly check!!!

This is my form...

   <s:form action="cules" name="form1" >  

[Bear Bibeault]

<s:form ... is not valid HTML. If this is a Struts question, this is not the place to ask it. If it's an HTML question, don't show Struts markup here.>

[Pradeep Adibatla]

Bear,please move it to struts forum...I initially posted this is struts forum...

May be David might take a look...thanks!!!

[David Newton]

Please start a new thread; this has gone back and forth already.