Echo Category form field type title in Module

Question

I'm building a module and using the Category Form Field Type, as outlined in the Joomla docs here https://docs.joomla.org/Category_form_field_type

In the module XML I've used the following:

<field name="catOne" type="category" extension="com_content" label="Select a category" description="" />
<field name="catTwo" type="category" extension="com_content" label="Select a category" description="" />
<field name="catThree" type="category" extension="com_content" label="Select a category" description="" />
<field name="catFour" type="category" extension="com_content" label="Select a category" description="" />

Whenever I echo these in the frontend, I'm just getting the category ID - how can I echo the category title and it's related URL for each of the above variables?

Answer 1

Yo have the ID of the category, so you can perform a database query to get the title, like so:

Get the title from the ID:

// Get the category parameter value 
// Define a default value of 0
$cat_id = $params->get('catOne', 0);

// Get instance of database connection
$db = JFactory::getDbo();

// Query the #__categories table in the database
$query = $db->getQuery(true);
$query->select($db->quoteName('title'))
      ->from($db->quoteName('#__categories'))
      ->where($db->quoteName('id') . ' = '. (int)$cat_id);
$db->setQuery($query);

// Try and get the result
try
{
    $result = $db->loadResult();
}
catch (Exception $e)
{
    // If there is no result, make the variable empty
    $result = '';
}

// Display the result
echo $result;

Display a Link:

To display the URL for the category, you will need to import com_content's router:

require_once JPATH_SITE . '/components/com_content/helpers/route.php';

$link = JRoute::_('index.php?option=com_content&view=category&layout=blog&id=' . $cat_id);

echo '<a href="' . $link . '">' . $result . '</a>';

For multiple params, use a function:

function displayCategoryLink($id)
{
    require_once JPATH_SITE . '/components/com_content/helpers/route.php';

    $db = JFactory::getDbo();

    $query = $db->getQuery(true);
    $query->select($db->quoteName('title'))
          ->from($db->quoteName('#__categories'))
          ->where($db->quoteName('id') . ' = '. (int)$id);
    $db->setQuery($query);

    try
    {
        $result = $db->loadResult();
    }
    catch (Exception $e)
    {
        $result = '';
    }

    $link = JRoute::_('index.php?option=com_content&view=category&layout=blog&id=' . $id);   
    $html = '<a href="' . $link . '">' . $result . '</a>';

    return $html;
}


displayCategoryLink($params->get('catOne', 0));
displayCategoryLink($params->get('catTwo', 0));
displayCategoryLink($params->get('catThree', 0));
displayCategoryLink($params->get('catFour', 0));

The function above is just basic. I would of course suggest you put the function in a class, in a helper.php file and call it properly

Hope this helps