Empty accesskeys in navigation

[CMSworker]

Affected version(s)

5.0.7

Description

In a local test installation of Contao 5.0.7 in XAMPP (PHP 8.1.6) I noticed multiple empty accesskey="" in the HTML source code of navigation blocks. I did not set any keyboard shortcuts in the page settings in the backend. The accesskey fields in the backend show 0 as default value.

To investigate it, I made a copy of the template nav_default.html5 and added a variable dump with

echo \Contao\Template::dumpTemplateVars();

In the array lists accesskey => false is defined for all navigation elements.

The accesskey is generated in this line in the template file:

contao/core-bundle/contao/templates/navigation/nav_default.html5

Line 7 in 015787f

<li<?php if ($item['class']): ?> class="<?= $item['class'] ?>"<?php endif; ?>><a href="<?= $item['href'] ?>" title="<?= $item['pageTitle'] ?: $item['title'] ?>"<?php if ($item['class']): ?> class="<?= $item['class'] ?>"<?php endif; ?><?php if ('' !== $item['accesskey']): ?> accesskey="<?= $item['accesskey'] ?>"<?php endif; ?><?= $item['target'] ?><?= $item['rel'] ?? '' ?><?php if (!empty($item['subitems'])): ?> aria-haspopup="true"<?php endif; ?>><?= $item['link'] ?></a><?= $item['subitems'] ?? '' ?></li>

To avoid the generation of the empty accesskeys I modified this snippet:
<?php if ('' !== $item['accesskey'] ): ?>
to this:
<?php if ('' !== $item['accesskey'] && $item['accesskey'] != false ): ?>

If someone can confirm the generation of empty accesskeys, it could be fixed in the core template.

[leofeyer]

It should probably be <?php if (!$item['accesskey']): ?> or <?php if (!empty($item['accesskey'])): ?>.

[CMSworker]

<?php if (!$item['accesskey']): ?> doesn't work.

<?php if (!empty($item['accesskey'])): ?> works. Thank you.

[CMSworker]

@ausi noted that the change "would break accesskey="0""
and suggested <?php if ('' !== (string) $item['accesskey']): ?>

I tested ausi's variant, it would work.

BUT I noticed that you can't declare accesskey 0 in Contao 5.0.7, at least in my test installation.

In the online demo (Contao 4.13.14) the input field for page accesskeys looks like this:

In my local Contao 5.0.7 installation it looks like this by default:

I did not enter the zero number. 0 is the default value. When you save the page with accesskey 0, it will not be rendered in the frontend's HTML code, no matter how I change the nav_default.html5 template.

I also noticed you can only enter numbers in this field. When you enter any letter and save the page, it gets converted to a number. Is this behaviour correct/intended for accesskeys?

[fritzmg]

This is actually an accidental change from #4797. I'll provide a PR to fix it.

[fritzmg]

See #5590