Flag indicating whether the field is required. TRUE if a value for this field is required when used with this bundle, FALSE otherwise. Currently

Field-type specific settings. An array of key/value pairs. The keys and default values are defined by the field type.

public FieldConfigBase::setRequired($required)

public FieldConfigBase::getItemDefinition()

public FieldConfigBase::addConstraint($constraint_name, $options =

public FieldConfigBase::onDependencyRemoval(array $dependencies)

public FieldConfigBase::addPropertyConstraints($name, array $constraints)

public FieldConfigBase::getDescription()

public FieldConfigBase::setDefaultValueCallback($callback)

public FieldConfigBase::getTargetBundle()