Update User "Field Type" for Entry in Plugin

Question

I have a channel called "Groups", with a users field type called members for the entries. I need to be able to add/remove users to the members entry field via plugin.

What I've tried is:

// criteria
$criteria = craft()->elements->getCriteria(ElementType::Entry);

// filter
$criteria->slug     = 'groupNameHere';

// section
$criteria->section('groups');

// get entry
$entries = $criteria->find();

foreach($enries as $entry)
{
    // get current members of group 
    $members = $entry['members'];

    // add new user model to $members
    $members[] = craft()->users->getUserByUsernameOrEmail("newUserEmailHere");

    // update field with new $members array
    $entry->getContent()->setAttribute('members', $members);

    // save
    craft()->entries->saveEntry($entry);
}

This simply clears the previous members value for the group, without even adding the new user. I can't find anything online about updating this type of field-type via plugin so I'm just guessing how to do this. Does anyone know the right way to do this?

Any information would hugely help! Thanks!

Answer 1

When a User field is saved, it takes an array of user IDs only – not complete UserModel objects. Something like this should work:

// get IDs for current members of group 
$members = $entry->members->ids();

// add new user ID to members
$members[] = $addUser->id;

// update field with new $members array
$entry->getContent()->setAttribute('members', $members);

The rest of your code looks fine, except for a minor typo – $enries should be $entries.