Struts 2 + Updating target element with content returned from url

[Sunil Anna]

I'm facing an issue while updating an sx:div element with content returned from a url.
Here is my JSP

<s:url id="ajaxSubmit" value="/ns/DrawSparklineSubmit.action" />
<sx:submit highlightColor="lightGrey" type="submit" href="%{ajaxSubmit}" formId="sparkForm" label="Chart" 
targets="SparklineImageCodeId" value="Chart"/> 

<sx:div name="SparklineImageCode" id="SparklineImageCodeId" theme="ajax" parseContent="false" loadingText="reloading" 
showLoadingText="true" executeScripts="true" errorText="Failed.." refreshOnShow="true" value="--" title="Div" showErrorTransportText="true"/>

DrawSparklineSubmit action points to process() method of DrawSparkLinesAction.java

In this process() method I'm updating the div element by invoking

setSparklineImageCode("data='" + getData() + "'<//p>"); 

But that's not working. The div element is not getting updated with any data. Am I missing sth here?

[David Newton]

What are you expecting to appear in the target div?

How is the Ajax action creating its output?

[Sunil Anna]

Thanks David,

I'm trying to send an html text back to browser. It's an <img ... tag with some attributes set (It'd appear as it is on browser, and it's not for showing an image).
On Submit button press I'm invoking process() method that tries to set the contents of sx:div tag

<sx:div name="sparklineImageCode"... 

by invoking setSparklineImageCode()

public void process(){
		setSparklineImageCode("<img src='" + getSource() + "'</img>");
	}

I can not exactly return a string from this method (as struts would try to interpret it as an action result). Then, how should I update this div tag?
Please pardon my ignorance I'm new to Struts and AJAX.

[David Newton]

You have to produce output somehow, like via a JSP or something.

So the process() method might return SUCCESS, and the JSP would consist of the image tag:

<img source"/>"/>

(Or something similar, anyway.)

Things like this are really easy to test: just go to the URL of the Ajax action and see if it produces the output you expect. This one wouldn't create any output, because there's no way for it to.

[Sunil Anna]

Thank you David,

It seems the only way to update UI components through AJAX in Struts 2 is to have a JSP. That would replace the contents of the UI component. I had tried this approach, though I don't remember it worked. But this seems a lousy way to me as in my case I'd have to create a JSP for every div component update.

Anyway Thanks for your help David

[David Newton]

You don't *have* to create a JSP, you could write directly to the response, but in general that's a Bad Idea.

If you're creating HTML, use the mechanisms JEE provides to do so. Generating HTML in servlets is almost never something to start doing.