CODEWITHSUNDEEP
javajspjstl
stivlo
stivlo

Reputation: 85476

Alternating row color in JSTL with nested loop

I would like to alternate row color for each row, I know how to alternate row color using varStatus in a forEach loop. However now, I've a nested loop.

<c:forEach var="aPermission" items="${Permissions}" varStatus="loop1">
    <c:forEach var="anIpRange" items="${aPermission.ipRanges}" varStatus="loop2">
    <tr class="${loop2.index % 2 == 0 ? 'row0' : 'row1'}"> [...]
    </c:forEach>
</c:forEach>

The code above is using only 'loop2' varStatus, and is only an approximation. How to solve the problem? I've to introduce my count variable or there are better ways?

Upvotes: 2

Views: 3531

Answers (3)

JB Nizet
JB Nizet

Reputation: 691715

Simply use a dedicated counter:

<c:set var="counter" value="${0}"/>
<c:forEach var="aPermission" items="${Permissions}" varStatus="loop1">
    <c:forEach var="anIpRange" items="${aPermission.ipRanges}" varStatus="loop2">
        <tr class="${counter % 2 == 0 ? 'row0' : 'row1'}"> [...] </tr>
        <c:set var="counter" value="${counter + 1}"/>
    </c:forEach>
</c:forEach>

Upvotes: 5

Igor Konoplyanko
Igor Konoplyanko

Reputation: 9374

There is an 1-line way.

UPD. I have been mistaken first time. there is the right solution without redundant variables.

<tr class="${(loop2.index*fn:length(aPermission.ipRanges) + loop1.index) % 2 == 0 ? 'row0' : 'row1'}">

Upvotes: 1

Bozho
Bozho

Reputation: 597076

  • store a sum of all iterated items (using <c:set>). You can do this in the outer loop by calculating currentSum = currentSum + fn:length(aPermission.ipRanges). Do this after the inner loop
  • use currentSum + loop2.index to check the color for each row.

Upvotes: 2

Related Questions