J3.x:Developing an MVC Component/Adding configuration

<?php
/**
 * @package     Joomla.Administrator
 * @subpackage  com_helloworld
 *
 * @copyright   Copyright (C) 2005 - 2018 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE.txt
 */

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

/**
 * HelloWorlds View
 *
 * @since  0.0.1
 */
class HelloWorldViewHelloWorlds extends JViewLegacy
{
	/**
	 * Display the Hello World view
	 *
	 * @param   string  $tpl  The name of the template file to parse; automatically searches through the template paths.
	 *
	 * @return  void
	 */
	function display($tpl = null)
	{
		
		// Get application
		$app = JFactory::getApplication();
		$context = "helloworld.list.admin.helloworld";
		// Get data from the model
		$this->items			= $this->get('Items');
		$this->pagination		= $this->get('Pagination');
		$this->state			= $this->get('State');
		$this->filter_order 	= $app->getUserStateFromRequest($context.'filter_order', 'filter_order', 'greeting', 'cmd');
		$this->filter_order_Dir = $app->getUserStateFromRequest($context.'filter_order_Dir', 'filter_order_Dir', 'asc', 'cmd');
		$this->filterForm    	= $this->get('FilterForm');
		$this->activeFilters 	= $this->get('ActiveFilters');

		// Check for errors.
		if (count($errors = $this->get('Errors')))
		{
			JError::raiseError(500, implode('<br />', $errors));

			return false;
		}

		// Set the submenu
		HelloWorldHelper::addSubmenu('helloworlds');

		// Set the toolbar and number of found items
		$this->addToolBar();

		// Display the template
		parent::display($tpl);

		// Set the document
		$this->setDocument();
	}

	/**
	 * Add the page title and toolbar.
	 *
	 * @return  void
	 *
	 * @since   1.6
	 */
	protected function addToolBar()
	{
		$title = JText::_('COM_HELLOWORLD_MANAGER_HELLOWORLDS');

		if ($this->pagination->total)
		{
			$title .= "<span style='font-size: 0.5em; vertical-align: middle;'>(" . $this->pagination->total . ")</span>";
		}

		JToolBarHelper::title($title, 'helloworld');
		JToolBarHelper::addNew('helloworld.add');
		JToolBarHelper::editList('helloworld.edit');
		JToolBarHelper::deleteList('', 'helloworlds.delete');
		JToolBarHelper::preferences('com_helloworld');
	}
	/**
	 * Method to set up the document properties
	 *
	 * @return void
	 */
	protected function setDocument() 
	{
		$document = JFactory::getDocument();
		$document->setTitle(JText::_('COM_HELLOWORLD_ADMINISTRATION'));
	}
}

<?php
/**
 * @package     Joomla.Administrator
 * @subpackage  com_helloworld
 *
 * @copyright   Copyright (C) 2005 - 2018 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE.txt
 */
// No direct access
defined('_JEXEC') or die('Restricted access');

/**
 * Hello Table class
 *
 * @since  0.0.1
 */
class HelloWorldTableHelloWorld extends JTable
{
	/**
	 * Constructor
	 *
	 * @param   JDatabaseDriver  &$db  A database connector object
	 */
	function __construct(&$db)
	{
		parent::__construct('#__helloworld', 'id', $db);
	}
	/**
	 * Overloaded bind function
	 *
	 * @param       array           named array
	 * @return      null|string     null is operation was satisfactory, otherwise returns an error
	 * @see JTable:bind
	 * @since 1.5
	 */
	public function bind($array, $ignore = '')
	{
		if (isset($array['params']) && is_array($array['params']))
		{
			// Convert the params field to a string.
			$parameter = new JRegistry;
			$parameter->loadArray($array['params']);
			$array['params'] = (string)$parameter;
		}
		return parent::bind($array, $ignore);
	}
}

<?php
/**
 * @package     Joomla.Administrator
 * @subpackage  com_helloworld
 *
 * @copyright   Copyright (C) 2005 - 2018 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE.txt
 */

// No direct access
defined('_JEXEC') or die('Restricted access');
JHtml::_('behavior.formvalidator');
?>
<form action="<?php echo JRoute::_('index.php?option=com_helloworld&layout=edit&id=' . (int) $this->item->id); ?>"
    method="post" name="adminForm" id="adminForm" class="form-validate">
	<div class="form-horizontal">
		<?php foreach ($this->form->getFieldsets() as $name => $fieldset): ?>
			<fieldset class="adminform">
				<legend><?php echo JText::_($fieldset->label); ?></legend>
				<div class="row-fluid">
					<div class="span6">
						<?php foreach ($this->form->getFieldset($name) as $field): ?>
							<div class="control-group">
								<div class="control-label"><?php echo $field->label; ?></div>
								<div class="controls"><?php echo $field->input; ?></div>
							</div>
						<?php endforeach; ?>
					</div>
				</div>
			</fieldset>
		<?php endforeach; ?>
	</div>
	<input type="hidden" name="task" value="helloworld.edit" />
	<?php echo JHtml::_('form.token'); ?>
</form>

Array
(
    [details] => stdClass Object
        (
            [name] => details
            [label] => COM_HELLOWORLD_HELLOWORLD_DETAILS
            [description] => 
        )

    [params] => stdClass Object
        (
            [name] => params
            [label] => JGLOBAL_FIELDSET_DISPLAY_OPTIONS
            [description] => 
        )

)

<?php
/**
 * @package     Joomla.Administrator
 * @subpackage  com_helloworld
 *
 * @copyright   Copyright (C) 2005 - 2018 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE.txt
 */

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

/**
 * HelloWorld Model
 *
 * @since  0.0.1
 */
class HelloWorldModelHelloWorld extends JModelItem
{
	/**
	 * @var object item
	 */
	protected $item;

	/**
	 * Method to auto-populate the model state.
	 *
	 * This method should only be called once per instantiation and is designed
	 * to be called on the first call to the getState() method unless the model
	 * configuration flag to ignore the request is set.
	 *
	 * Note. Calling getState in this method will result in recursion.
	 *
	 * @return	void
	 * @since	2.5
	 */
	protected function populateState()
	{
		// Get the message id
		$jinput = JFactory::getApplication()->input;
		$id     = $jinput->get('id', 1, 'INT');
		$this->setState('message.id', $id);

		// Load the parameters.
		$this->setState('params', JFactory::getApplication()->getParams());
		parent::populateState();
	}

	/**
	 * Method to get a table object, load it if necessary.
	 *
	 * @param   string  $type    The table name. Optional.
	 * @param   string  $prefix  The class prefix. Optional.
	 * @param   array   $config  Configuration array for model. Optional.
	 *
	 * @return  JTable  A JTable object
	 *
	 * @since   1.6
	 */
	public function getTable($type = 'HelloWorld', $prefix = 'HelloWorldTable', $config = array())
	{
		return JTable::getInstance($type, $prefix, $config);
	}

	/**
	 * Get the message
	 * @return object The message to be displayed to the user
	 */
	public function getItem()
	{
		if (!isset($this->item)) 
		{
			$id    = $this->getState('message.id');
			$db    = JFactory::getDbo();
			$query = $db->getQuery(true);
			$query->select('h.greeting, h.params, c.title as category')
				  ->from('#__helloworld as h')
				  ->leftJoin('#__categories as c ON h.catid=c.id')
				  ->where('h.id=' . (int)$id);
			$db->setQuery((string)$query);
		
			if ($this->item = $db->loadObject()) 
			{
				// Load the JSON string
				$params = new JRegistry;
				$params->loadString($this->item->params, 'JSON');
				$this->item->params = $params;

				// Merge global params with item params
				$params = clone $this->getState('params');
				$params->merge($this->item->params);
				$this->item->params = $params;
			}
		}
		return $this->item;
	}
}

<?php
/**
 * @package     Joomla.Administrator
 * @subpackage  com_helloworld
 *
 * @copyright   Copyright (C) 2005 - 2018 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE.txt
 */

// No direct access to this file
defined('_JEXEC') or die('Restricted access');

/**
 * HTML View class for the HelloWorld Component
 *
 * @since  0.0.1
 */
class HelloWorldViewHelloWorld extends JViewLegacy
{
	/**
	 * Display the Hello World view
	 *
	 * @param   string  $tpl  The name of the template file to parse; automatically searches through the template paths.
	 *
	 * @return  void
	 */
	function display($tpl = null)
	{
		// Assign data to the view
		$this->item = $this->get('Item');

		// Check for errors.
		if (count($errors = $this->get('Errors')))
		{
			JLog::add(implode('<br />', $errors), JLog::WARNING, 'jerror');

			return false;
		}

		// Display the view
		parent::display($tpl);
	}
}

<?php
/**
 * @package     Joomla.Administrator
 * @subpackage  com_helloworld
 *
 * @copyright   Copyright (C) 2005 - 2018 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE.txt
 */

// No direct access to this file
defined('_JEXEC') or die('Restricted access');
?>
<h1><?php echo $this->item->greeting.(($this->item->category and $this->item->params->get('show_category'))
                                      ? (' ('.$this->item->category.')') : ''); ?>
</h1>