newsletter-bundle/src/Resources/contao/dca/tl_module.php
public function getChannels()
	{
		if (!$this->User->isAdmin && !\is_array($this->User->newsletters))
		{
			return array();
		}

		$arrChannels = array();
		$objChannels = $this->Database->execute("SELECT id, title FROM tl_newsletter_channel ORDER BY title");

		while ($objChannels->next())
		{
			if ($this->User->hasAccess($objChannels->id, 'newsletters'))
			{
				$arrChannels[$objChannels->id] = $objChannels->title;
			}
		}

		return $arrChannels;
	}
public function getChannels()
	{
		if (!$this->User->isAdmin && !\is_array($this->User->newsletters))
		{
			return array();
		}

		$arrChannels = array();
		$objChannels = $this->Database->execute("SELECT id, title FROM tl_newsletter_channel ORDER BY title");

		while ($objChannels->next())
		{
			if ($this->User->hasAccess($objChannels->id, 'newsletters'))
			{
				$arrChannels[$objChannels->id] = $objChannels->title;
			}
		}

		return $arrChannels;
	}
Get all channels and return them as array

@return array