import * as React from 'react';
import { FormSpy } from 'react-final-form';

function submitButtonSpy() {
  return (
    <FormSpy subscription={{ pristine: true, submitting: true, valid: true }}>
      {({ pristine, submitting, valid }) => {
        return (
          <button type="submit" disabled={submitting || pristine || !valid}>
            Submit
          </button>
        );
      }}
    </FormSpy>
  );
}