How to push params into an admin form

[Paul van Haren]

I'm developing a component that has a lot of item parameters. I'd like to store these as params in the database. In the XML file for the form definition, these parameters are grouped into a fields section:

<fields name="params">

<fieldset name="parameters">

<field name="key" type="text" default="" label="MY_KEY" />

<field name="logo" type="filelist" default="default" label="LOGO_LABEL" 
directory="administrator/components/com_mycomponent/assets/images/logos" hide_none="1" hide_default="1" />

This works fine for creating the form and saving the data. I can see in the database that in the params data the JSON string is containing the values for "key" and "logo".  

When loading the form and item data, I can find that the this takes place as expected:

public function display($tpl = null)

{

// Get the Data

$this->form = $this->get('Form');
$this->item = $this->get('Item');

parent::display($tpl);

        }

When rendering the form, the renderer calls 

       <?php echo $this->form->renderFieldSet("parameters"); ?>

Again, this works fine apart from the fact that the values of the parameters are not in the form. These parameters are accessible as $this->item->params['data']. What is needed to have the form make use of these loaded values?

Your help is appreciated.

[Paul van Haren]

FIXED.

In the model code (com_mycomponent->models->mycomponent.php) , there is the implementation of loadFormData(). Typically, it looks like this:

protected function loadFormData()

{

// Check the session for previously entered form data.

$data = JFactory::getApplication()->getUserState('com_mycomponent.edit.mycomponent.data',array());

if (empty($data))

{

$data = $this->getItem();

}

return $data;

}

Adding the lines just before the return statement

$this->preprocessData('com_mycomponent.mycomponent', $data);

$params = $data->params['data'];

$data->params = $params;

solves the issue.