About forms, which items are true?
The following method is not part of the FormTypeInterface interface.
setDefaultOptions(...);
The following event can be used to modify the submitted data.
form.pre_set_data (CONST FormEvents::PRE_SET_DATA)
In a controller, the following method takes a FormTypeInterface object as its first argument.
$this->createForm();
After processing a form by the following method, the submitted data is accessible by the getData() method.
$form->handleRequest($request);