How to access the nested tag of a struts tag?

Question

I am using the following JavaScript code to set the value of an element.

document.getElementById('alert['+i+']').innerHTML = "alert";

The element is nested in a Struts set tag. (The ID match up, the fault is not there.)

<s:set var="alert" >
   <span id="<s:property value='"alert"+{#stat.index+4}' />"></span>
</s:set>

the set tag var is used by a Struts if tag.

<s:if test="%{#alert == 'alert'}">
    //some code         
</s:if>

when the span tag is outside of the set tag, the value of the span tag is set to "alert" correctly. However when inside the struts set tag. the span tag cannot be found.

How do I successfully set the value of the set tag? either using the span tag or setting the value of the set tag directly. Or can I somehow inject the "alert" value in the if tag directly?

I have used google and youtube to find answers. I have tried to put the span tag directly in the if tag. I have tried using document.querySelector() but I couldn't get it to work with strut tags.

What does the generated output actually look like? Did you inspect the element? — epascarello, Nov 17 '22 at 14:07
Uncaught TypeError: Cannot set properties of null (setting 'innerHTML') — MicSar, Nov 17 '22 at 14:11
WHAT IS THE GENERATE HTML? Inspect the element, look at the id. What is the id? My guess it does not have the random [ and ] you inserted. — epascarello, Nov 17 '22 at 14:31
The Id match up. like I said when you put the span outside the set tag, it prints "alert" — MicSar, Nov 17 '22 at 15:03
https://stackoverflow.com/questions/14028959/why-does-jquery-or-a-dom-method-such-as-getelementbyid-not-find-the-element — epascarello, Nov 17 '22 at 16:15
Define successful set the value of the set tag? From my point it's set correctly but you cannot use it's value. — Roman C, Nov 17 '22 at 17:58
@MicSar The span tag is not available because you put it in the body of set tag. — Roman C, Nov 19 '22 at 19:37

Roman C · Answer 1 · 2022-11-19T19:41:44.037

1

If you are using document.getElementById() in JavaScript code, then the element with the id should be available in the DOM. But it's not available because you put it in the Struts <s:set> tag. It's not UI tag and it doesn't render any HTML elements.

You can set the value of alert variable in the value attribute. It allows to apply an OGNL expression there.

<s:set var="alert" value="%{'alert'+(#stat.index+4)}"/>

<span id="<s:property value='%{#alert}'/>">
</span>

Then if you use <s:if> tag the value of the variable alert should be found in the context.

edited Nov 19 '22 at 19:41

answered Nov 19 '22 at 18:58

Roman C

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If this answer helped you then you should mark it as accepted and upvote if it's possible. The checkbox and vote up controls are on the left of the answer. – Roman C Nov 25 '22 at 16:34

How to access the nested tag of a struts tag?

1 Answers1