atk4\data\Reference_SQL_One::withTitle PHP Method

$order->hasOne('user_id', 'User')->addTitle(); This will add expression 'user' equal to ref('user_id')['name'];

public withTitle ( array $defaults = [] )
$defaults	array	Properties

    public function withTitle($defaults = [])
    {
        $this->addTitle($defaults);
        return $this;
    }

Reference_SQL_One