Add support for dependent / chained AssociativeField

[Seb33300]

Hello,

Fixes #4716

Here is a proposal to support dependent/chained dropdowns on AssociationField.
This allows the options of an AssociationField to vary based on the values selected in other form fields.

This feature only works on AssociationField with the autocomplete feature enabled.
You will also need to use setQueryBuilder() to filter your results. A new param $dependsOn has been added to the callable for this purpose.

Here is my proposal to support dependent/chained dropdowns on AssociationField.
This allows the options of an AssociationField to change based on the values selected in other form fields.

This feature only works with AssociationField when the autocomplete feature is enabled.
You will also need to use setQueryBuilder() to filter the results. For this purpose, a new $dependsOn parameter has been added to the callable.

Example usage:

yield CountryField::new('country');

yield AssociationField::new('state')
    ->autocomplete(
        // Specify the field(s) this AssociationField depends on
        dependsOn: 'country'
    )
    ->setQueryBuilder(function (QueryBuilder $queryBuilder, array $dependsOn) {
        return $queryBuilder
            ->andWhere('entity.country = :country')
            ->setParameter('country', $dependsOn['country']);
    })

You can also depend on multiple fields:

yield AssociationField::new('building');

yield NumberField::new('numberOfParticipants');

yield AssociationField::new('meetingRoom')
    ->autocomplete(
        dependsOn: ['building', 'numberOfParticipants']
    )
    ->setQueryBuilder(function (QueryBuilder $queryBuilder, array $dependsOn) {
        return $queryBuilder
            ->andWhere('entity.building = :building')
            ->andWhere('entity.capacity >= :numberOfParticipants')
            ->setParameter('building', $dependsOn['building'])
            ->setParameter('numberOfParticipants', $dependsOn['numberOfParticipants']);
    });