valueTransformer empty to null value

[marco-origam]

I need the field to be null when it's empty like below:

{
  name: null
}

So, im using valueTransformer as follows:

...
name: 'name',
valueTransformer: (value) {
  if (value == null || value.trim().isEmpty) {
    return null;
  }
  return value;
},
...

But, im still getting:

{
  name: ""
}

Is there a way i can achieve it?

[Schrolli91]

I have the same Problem here...

valueTransformer: (String? value) {
  if (value == null) return null;
  return double.tryParse(value);
},

but the field is always exact the data, were i have written into the field.
I read with

if (formKey.currentState!.saveAndValidate()) {
  dynamic data = formKey.currentState?.value;

[Schrolli91]

Or is it possible to get the transformed values this way?
formKey.currentState!.getTransformedValue('quantity')
Can't find documentation about that.

[Schrolli91]

Ok i see - the Problem is the valueTransformer implementation.
If i return a null the original value will be used. A Bug in my opinion, because null can be a valid value.
dynamic get transformedValue => widget.valueTransformer?.call(value) ?? value;