Django template cycle for alternating rows - without loop

Question

Perhaps this is a non-question, but how do you make use of the Django {% cycle %} functionality, or something similar, when you're not in a loop? Specifically, I have an HTML table that I'm writing by hand, since it's not the sort of thing you need to do in a loop. I want the rows to alternate, like this:

   <tr class="{% cycle 'even' 'odd'%}"></tr>
   <tr class="{% cycle 'even' 'odd'%}"></tr>
   <tr class="{% cycle 'even' 'odd'%}"></tr>

But I'm not using a loop, so this always results in even. I don't want a situation where I want to insert one row later, and then have to change the classes of all rows beneath it by hand. Am I just being petty? How would you cycle without being in a loop?

Answer 1

There's a section devoted to using cycle outside of loops on the docs:

In some cases you might want to refer to the next value of a cycle from outside of a loop. To do this, just give the {% cycle %} tag a name, using "as", like this:

{% cycle 'row1' 'row2' as rowcolors %}

From then on, you can insert the current value of the cycle wherever you'd like in your template by referencing the cycle name as a context variable. If you want to move the cycle onto the next value, you use the cycle tag again, using the name of the variable. So, the following template:

<tr>
    <td class="{% cycle 'row1' 'row2' as rowcolors %}">...</td>
    <td class="{{ rowcolors }}">...</td>
</tr>
<tr>
    <td class="{% cycle rowcolors %}">...</td>
    <td class="{{ rowcolors }}">...</td>
</tr>

would output:

<tr>
    <td class="row1">...</td>
    <td class="row1">...</td>
</tr>
<tr>
    <td class="row2">...</td>
    <td class="row2">...</td>
</tr>

So in your case, you'd just declare it once and then call {% cycle name %} on every row.