todo

• update atk4/data/Reference/ContainsMany with new ui and system = false property
  As of now, field using containsMany need to be explicitly set using system property to false in order to appear in form.
  $this->containsMany('Addresses', [Address::class, 'system' => false]); ,
• update for use with unloaded model
  This code in Form is causing issue: $model = $f->reference->refModel(); because when trying to create containsMany reference model on a new record, ContainsMany::getDefaultPersistence($model) in atk4/data throws exceptions: 'model should be loaded.'

if ($f->type === 'array') {
            $limit = ($f->reference instanceof ContainsMany) ? 0 : 1;
            $model = $f->reference->refModel();
            $fallback_seed = ['MultiLine', 'model' => $model, 'rowLimit' => $limit, 'caption' => $model->getModelCaption()];
        }

• decide if we keep __atkml value in containsMany record - __atkml is needed for multiline component in order to manage error properly.
• decide if we include Semantic-UI vue in atkjs package. As of now, if we want to have Multiline works in CRUD or in a form inside a modal, we have to explicitly load semantic-ui Vue package.

$app->useSuiVue();
$app->add(['CRUD'])->setModel($m);

Update

• add support for limiting number of record.
  ex: $f->addField('test', ['MultiLine', 'model'=> Model::class, 'rowLimit' => 2])
  Therefore containsOne will automatically use MultiLine using limit of 1 record.

• add support for Dropdown field in Multiline

• add model caption (see image below)

• add support for Dropdown options via 'ui' => 'multiline' property
  $this->hasOne('country_id', [new Country(), 'ui' => ['multiline' => ['dropdown' => ['search' => true]]]]);

usage:

class Client extends atk4\data\Model
{
    public $table = 'client';
    public $caption = 'Client';

    public function init()
    {
        parent::init();
        $this->addField('name');

        //use system = false until atk4\data is update.
        $this->containsMany('Addresses', [Address::class, 'system' => false]); 
    }
}

class Address extends atk4\data\Model
{
    public $caption = 'Address';

    public function init()
    {
        parent::init();
        $this->addField('street', ['required' => true]);
        $this->addField('city');
        $this->addField('country');
        $this->addField('postal_code');
    }
}

$f = $app->add('Form');
$f->setModel(new Client($db));