Create item in custom code

Hello,
After a submission form in frontend that create a first item, I want to create a second item automatically. I try to use your script that I found in the FAQ :
www.flexicontent.org/documentation/faq/7...-in-custom-code.html
I don't know exactly where I could insert this script (the best way), in the file form.php ? Or anywhere else ?
Thank you

you need to create a plugin and use onsubmit event to catch save event not ?

I don't know if a new plugin is necessary, for the moment I just tried to execute the script in a new file, create_item.php, to test it with a joomla menu item of type external link, in order to create a new item, so with :

$item_ID = 0;
$data = 0;

and I have an error message :
Fatal error: Call to a member function getError() on null in /mysite/create_item.php on line 198

196 if ( !$item_model->store($data) )
197 {
198 $msg = 'Failed to create the new item: '. $model->getError();
199 JLog::add($msg);
200 echo $msg."<br/>";
201 }

What's wrong ? Is there something else to do ?

Just an little question more, that can maybe explain the previous one; In the script, there is line 92 :

What 'custom' is supposed to be ?

Hello

You can duplicate plugin:
/plugins/flexicontent/flexinotify/flexinotify.php

and use event:
onAfterSaveItem

to do things,

but you cannot create an other item,
it will create a loop, because onAfterSaveItem will be triggered again

it is better to create a system plugin
and check if current URL is item saving URL

check current url has (e.g. backend URL)
&option=com_flexicontent&task=items.save