Dynamic forms with javascript

[Juan Acv]

Hello everybody:

I am trying to migrate a struts 1 funcionality to struts 2, and i need to enable /disable, show/hide items in a form, using javascript.

My question is, if i could do a submit in javascript like this:

    
<s:form method="post">
      <s:select name="country" label="Country" emptyOption="true"
      list="#application.countries" onchange="this.form.submit()" />
</s:form>

Only to refresh the form, and make visible another form options:

    
<c:choose>
      <c:when test="${country == 'spain'}">
            <s:select ...>
      </c:when>
      <c:otherwise>
            <s:select ...>
      </c:otherwise>
</c:choose>

Could i use an action defined like this, to call a method that only returns
a success? :

    
<action name="refreshForm" class="com.MyAction" method="refresh">
<result name="success">/WEB-INF/pages/myForm.jsp</result>
</action>

...
public class MyAction extends BaseAction {

[...]

       public String refresh() throws IOException {
              return SUCCESS;
       }
}

And could I add a javascript like this?:

    

<s:form method="post">
      <s:select name="country" label="Country" emptyOption="true"
       list="#application.countries" onchange="sending()" />
</s:form>

<script type="text/javascript">
function sending() {
       this.form.action = 'refreshForm';
       this.form.submit();
}
</script>

I used to make this, using the returned values in the request or in the session, and forwarding to the form again, in struts 1, but i have no idea how to make this in struts 2.

Thanks in advance.

[David Newton]

I'm not really sure what you're asking: ultimately the rendered HTML looks very similar regardless of which version of Struts you're using (and you don't appear to be using JavaScript to hide/show anything, at least not in the sample you posted), and the JavaScript that acts on the form would be nearly identical.

Are you having a specific issue?

[Juan Acv]

Ok, i don't know how to explain myself, my english is poor, and i know what i want to do, but only in struts 1, and i want to translate it to struts 2.


Well, I will try again:

I have a select, with an "onchange" trigger, because, depending on the value of this select, I will like to show/hide another select:

For example, i have countries, and, for example, if someone select "spain", i want to show another select:

    
   <s:form method="post">  
        <s:select name="country" label="Country" emptyOption="true"   
         list="#application.countries" onchange="..." />  


         <if test="${country == 'spain'}">
             <s:select ...>
         </c:if>
    </s:form>  

In struts 1, i did it using javascript, making a submit and sending a hidden input value to the action, with this value (will say, a "REFRESH" string) recovered in the request, in the action, the action only makes a forward to the form again, and then, recovering the value from the request, in the jsp, i can make the "if" comparsion (I can put the code, if it is not clear), but i don't know how to make this in struts 2, i am newbie on it, and i realize that the binding beetween actions and jsp's have changed.

I dont know if in struts 2 it is possible to make a "fake submit" only to recover the values that someone have selected, and then, make possible to show/hide another parts on the form.

I can't explain myself better. Maybe it is a stupid question, and it's very easy with the new framework tools, but i am in a hurry, and i try to read about struts 2 as quick as i can, and for my project, i believe i only need to know basic struts 2 and how to develop dynamic forms. if someone can answer me this question, i will be grateful.

Greetings.

[David Newton]

It's not a fake submit--it's a real submit. And you're not showing or hiding things using JavaScript--you're using JSTL.

In any case, Struts 2 normally exposes values by exposing an action property as opposed to explicitly setting attributes in the request or session. A publicly-visible getter in the action is all that's needed to send a value to a JSP. You should run through the Struts 2 tutorial on the Struts 2 documentation wiki--it takes only a very short time and will show you all you need to accomplish what you're trying to do.

[Juan Acv]

Yes, i know that struts 2 now encapsulates the data in beans, what i really don't undertand, it is how to call a specific method in an action or how to say to an action execute() method "now just refresh" or "now save my data", just the way a did it in struts 1.

Ok, sorry, i will take a look to the tutorial and examples.

Greetings.

[David Newton]

Just call the action mapping that does what you want--I don't understand what the confusion is.

[Juan Acv]

So, i return to my first question:

I can have a refresh() method, map it:

   

<action name="refresh" class="example.MyAction" method="refresh">
     ....
</action>

public class MyAction extends BaseAction {  
  
      [...]  
   
       public String refresh() throws IOException {  
               return INPUT;  
       }  
}  

and submit the action in javascript:

    
 <script type="text/javascript">  
 function sending() {  
        this.form.action = 'refresh';  
        this.form.submit();  
 }  
 </script>  

no?

Maybe i need a lot of examples about how to bind actions with jsp.

Like i said, i will take a look to the tutorial

Greetings.

[David Newton]

The action mapping you're using in the JavaScript will work if: that's the complete path, but it should be absolute, not relative; and you're either using Struts 2.1 or you have configured Struts 2 to use extension-less mappings.

[Juan Acv]

I am using appfuse framework, it works with struts version 2.1.8, and, yes, i believe they use extension-less mapping, reading their tutorial:

http://appfuse.org/display/APF/Using+Struts+2


Thank you very much, you have saved my life (seriously)

Greetings.

[David Newton]

(Wouldn't it just have been quicker to try it?)

[Juan Acv]

After loosing my job, i have been very stressed, into a mess, trying to do this project, that it's very important to me. I have had to learn everything i thought i have learned yet about spring + hibernate, reading lot of documentation, etc...

I have been trying to translate a struts 1 application into struts 2 as quick as i could, instead of being patient and learn struts 2 starting with the basics.

I'm sorry to cause you so much trouble.

Thanks a lot.

[David Newton]

It's not much trouble--it's more a streamlining thing for *you*, not me.