Are you submitting a bug report or a feature request?

Bug? I guess.

What is the current behavior?

Form onChange is called only on attachToForm but it doesn't called when you remove an input.

working example: https://codesandbox.io/s/formsy-vnfvm?file=/src/index.js

I tried to put the error messages in French but I always get the error in English.

For example when the field is empty when it is required (FormBuilderValidators.required (context)), I have the message "This field cannot be empty".

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return

It will be nice to have style options for MsgBox: option to define class, different mods for each button (right now we can define mod but it is the same for both buttons). Also, it will be great to add icons to the MsgBox buttons (button consistency). Thanks!

Is your feature request related to a problem? Please describe.
Feature request: Expose "key" in key.js.

Thanks! I've used Formik in the past and your implementation is very easy to understand.
I needed to use textarea and checkboxes (modifying value to true/false), but the slots in Form don't give me access to the "key" to the store. So, I couldn't add custom components.

**Describe t

For a long time I thought this was impossible to do without writing toString/fromString functions for your custom types, but I just realized that you can make it work by instead using the list index of the options as the "value", and then in the onChange decoder use that index to retrieve the item from the passed in options list.

Here's a demo: https://ellie-app.com/7253Q8THR2xa1