<h3>Example of using #theme</h3>
<ul>
<li>Simple string</li>
<li>Simple <span>#markup</span> string</li>
<li class="custom-item-class">Custom item</li>
<li>Parent item
<ul>
<li>Simple string child</li>
<li class="custom-child-item-class">Second child item with custom attributes</li>
</ul>
</li>
</ul>
$items = array();
// A simple string item.
$items[] = 'Simple string';
// A simple string item as render array.
$items[] = [
'#markup' => 'Simple <span>#markup</span> string',
];
// Set custom attributes for a list item.
$items[] = [
'#markup' => 'Custom item',
'#wrapper_attributes' => array(
'class' => array('custom-item-class'),
),
];
// An item with a nested list.
$items[] = [
'#markup' => 'Parent item',
'children' => [
'Simple string child',
[
'#markup' => 'Second child item with custom attributes',
'#wrapper_attributes' => [
'class' => array('custom-child-item-class'),
],
],
],
];
$build['list'] = [
'#theme' => 'item_list',
'#items' => [
$this->t('This is some text that should be put in a list'),
$this->t('This is some more text that we need in the list'),
],
];
$build['theme_element'] = [
'#theme' => 'item_list',
'#title' => $this->t('Example of using #theme item_list'),
'#items' => $items,
];