php - How to map one class variable to two form fields in Symfony

I wold like to use Symfony 2.8 to create a form for data class, e.g.Task as used in the Symfony docs.

MyTask class uses an integer fieldflags to store a collection different bool values. For example the value ofis completed is stored as the first bit andis urgent as the second bit:

• Task is not completed and not urgent --> flags = 0
• Task is completed and not urgent --> flags = 1
• Task is not completed and urgent --> flags = 2
• Task is completed and urgent --> flags = 3
• ...

The problem: How can this single class field be mapped to two different form fields and back?

$builder
    // map first bit to checkbox
    ->add('is_complete', CheckboxType::class, array(
            ...
        )
    )
    // map second bit to selection box "normal"/"urgent"
    ->add('is_urgend', ChoiceType::class, array(
            ...
        )
    )
    ...
Copy code

What is the correct solution to solve this? Can this be handled by a Data Transformers? As far as I know, a transformer can translate a field of one to type to another type, but not one field to two fields. Is that correct?

The only solution I found so far, is to create a wrapper classTaskWrapper which does not use flags but offers different bool fields for the each flag value. This class could than be passed to the form instead of the originalTask class. Once the form is submitted the returned wrapper object could than be manually translated back to aTask object.

This would work, but it is not a clean solution. Is this the way to go or is there a better solution using Symfony tools?