Add additional input fields in an article

[Lis]

Hello everyone.
How can I add additional input fields into an article?
I want for example a extra text field called "Groups" and an additional Textfield called "Platform".

Thank you, Louis

[geung]

I don't know the answer to your question but have you looked at this extension, I think it does what you want:

"Generate own Contentelements and frontend modules, The administrator can define form fields, which can be filled with content by the editor"

dma_elementgenerator
Forum link here to extension

Apparently it currently only works up to 2.11 but you can get a working version for 3.0 via github - just google it

[Lis]

I found out how it works on my own:
You need to create a dca contao/system/modules/testmod/dca/tl_article.php:

$GLOBALS['TL_DCA']['tl_article']['palettes']['default'] = $GLOBALS['TL_DCA']['tl_article']['palettes']['default'].";{tl_example_legend},tl_example_input";
$GLOBALS['TL_DCA']['tl_article']['fields']['tl_example_input'] = array
(
	'label'                   => &$GLOBALS['TL_LANG']['MSC']['tl_example_input'],
	'inputType'               => 'text',
	'eval'                    => array('tl_class'=>'clr long'),
	'sql'                     => "char(1) NOT NULL default ''"
);