[FIXED] Print post number in reverse order from thymeleaf

Issue

<tbody>
                     <tr th:each="bean , beanStat : ${list}">
                            <td class="text-center" th:text="${beanStat.size-beanStat.count+1}+(${paging.cri.page}-1)*${cri.perPageNum}" >1</td>
                               <!--  paging.totalcount -->
                            
   <!--                  <tr th:each="bean , beanStat : ${list}">
                            <td class="text-center" th:text="${beanStat.size-beanStat.count+1}+(${paging.cri.page}-1)*${cri.perPageNum}" >1</td>
                               

First of all, I'm sorry for not speaking English well.

I want to number the articles, but I want to number them in reverse order. I think you can do it like below in jsp In thymeleaf, I wonder how to do this in reverse order (is there an index?)

Total number of records - ( (Current page number - 1) * I think it is the number of records displayed per page.

${(totalCount - status.index) - ( (currentPage - 1) * displayNum ) }

I implemented it like this, but I wonder if there is such a part as status.index in the thymeleaf.

enter image description here

Solution

There is an equivalent to your JSP approach in Thymeleaf - a set of iteration tracking attributes you can use when processing a list.

Assuming you have a Java list like this:

List<String> list = new ArrayList<>();
list.add("One");
list.add("Two");
list.add("Three");

Then you can use the following Thymeleaf:

<table>
    <thead>
        <tr>
            <th>Number</th>
            <th>Item</th>
        </tr>
    </thead>
    <tbody>
        <tr th:each="item, iterStat : ${list}">
            <td th:text="${iterStat.size - iterStat.count +1}"></td>
            <td th:text="${item}"></td>
        </tr>
    </tbody>
</table>

This generates:

<table>
    <thead>
        <tr>
            <th>Number</th>
            <th>Item</th>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td>3</td>
            <td>One</td>
        </tr>
        <tr>
            <td>2</td>
            <td>Two</td>
        </tr>
        <tr>
            <td>1</td>
            <td>Three</td>
        </tr>
    </tbody>
</table>

---

Update

If you want to add paging into the calculation, then your Java code needs to know:

• current page number
• maximum number of rows per page (there may be fewer in the final page)
• total number of records (all pages)

Let's assume I pass those 3 values from Java to my Thymeleaf model with some new data:

List<String> list = new ArrayList<>();
list.add("Alfa");
list.add("Bravo");
list.add("Charlie");
list.add("Delta");
list.add("Echo");

int currentPage = 1;
int rowsPerPage = 5;
int totalRecords = 9;

Now, the Thymeleaf changes to this:

<table>
    <thead>
        <tr>
            <th>Number</th>
            <th>Item</th>
        </tr>
    </thead>
    <tbody>
        <tr th:each="item, iterStat : ${list}">
            <td th:text="${totalRecords - (currentPage * rowsPerPage)
                    + rowsPerPage - iterStat.count +1}"></td>
            <td th:text="${item}"></td>
        </tr>
    </tbody>
</table>

For page 1 this generates:

<tbody>
    <tr>
        <td>9</td>
        <td>Alfa</td>
    </tr>
    <tr>
        <td>8</td>
        <td>Bravo</td>
    </tr>
    <tr>
        <td>7</td>
        <td>Charlie</td>
    </tr>
    <tr>
        <td>6</td>
        <td>Delta</td>
    </tr>
    <tr>
        <td>5</td>
        <td>Echo</td>
    </tr>
</tbody>

For page 2 (the final 4 items), we have:

List<String> list = new ArrayList<>();
list.add("Foxtrot");
list.add("Golf");
list.add("Hotel");
list.add("India");

int currentPage = 2;
int rowsPerPage = 5;
int totalRecords = 9;

Note: Only the current page number has changed. The rows per page and the total records: those values remain the same across all pages.

And the same Thymeleaf template generates this:

<tbody>
    <tr>
        <td>4</td>
        <td>Foxtrot</td>
    </tr>
    <tr>
        <td>3</td>
        <td>Golf</td>
    </tr>
    <tr>
        <td>2</td>
        <td>Hotel</td>
    </tr>
    <tr>
        <td>1</td>
        <td>India</td>
    </tr>
</tbody>

Answered By - andrewJames
Answer Checked By - Mildred Charles (JavaFixing Admin)