How can I know if JTable->save() is inserting or updating a record?

Question

I have a custom-made Joomla 3 component used to create users in the frontend and adding some fields to another table. Now, I must change a bit this procedure: I must send an email to the new user with his username and password when he's registered.

In teory, this is really trivial. In my model, I should update the save() function, and after saving I send the email. And that's correct. But the problem is: how can I know that I'm creating a new user, and not updating and old user? I've been looking at Joomla3's documentation, but I don't know how to do this...

Can you help me, please?

Answer 1

I tried all of the possible ways and the absolute safest option is to add a dispatcher before the save functions and afterwards detach it.

Implement the save function that way in your model:

public function save ($data)
{
    $dispatcher = JDispatcher::getInstance();
    $eventHandler = new EventHandler($dispatcher, $this);

    $return = parent::save($data);

    $dispatcher->detach($eventHandler);

    return $return;
}

Add the following class to your model:

class EventHandler extends JEvent
{

    private $model = null;

    public function __construct (&$subject, $model)
    {
        parent::__construct($subject);

        $this->model = $model;
    }

    public function onContentBeforeSave ($context, $event, $isNew)
    {}

    public function onContentAfterSave ($context, $event, $isNew)
    {
        if ($context != 'com_dpcalendar.event' && $context != 'com_dpcalendar.form')
        {
            return;
        }

        if ($isNew)
        {
            // send mail
        }
    }

    public function onContentBeforeDelete ($context, $event)
    {}

    public function onContentAfterDelete ($context, $event)
    {}

    public function onContentChangeState ($context, $pks, $value)
    {}
}

I know this looks like a big overhead but it will keep you save.

Answer 2

If your model is inherited from JModelAdmin class then you can check for new record like this:

$isNew = $this->getState($this->getName() . '.new');

Otherwise you should check the data you saving - has it primary key set or not. See this part of code of JModelAdmin class.