pre-check some items with checkbox plugins

[linque]

I use a 'checkbox' plugins for an element.
I use the following example to populate the checkbox list.

$db = JFactory::getDbo();
$db->setQuery('SELECT id, text FROM #__tablename');
$rows = $db->loadObjectList();
foreach ($rows as $row) {
$options[] = JHTML::_('select.option', $row->id, $row->text);
}
return $options;

All elements are unchecked. I would like to pre-check some of them.

 

[lousyfool]

You can do so with Javascript. If you google around a bit, you'll find tons of code examples.
Adopt it to your needs, then use it either in a form_X.js file or, eventually, in element JS.

 

[troester]

Maybe you can set it
https://api.joomla.org/cms-3/classes/JHtmlSelect.html#method_options

 

[linque]

I know the list of checked in a PHP (sql request), non in JS
Is it possible to check it in PHP ?

 

[troester]

https://api.joomla.org/cms-3/classes/JHtmlSelect.html#method_options
is php

 

[linque]

I don't understand how to insert the checked ccommand in the script.