How to implement a working checkbox component in Formik 1.5.8

#formik #react #javascript

I was building a form with Formik and I needed a single checkbox to mark a post as "published". In Formik 1.5.8, my values values weren't mapping correctly to checkboxes, so I created a generic Checkbox component to use instead of the Formik Field component.

import { Field } from "formik";

export default function Checkbox({ id, name, className }) {
  return (
    <>
      <Field
        name={name}
        render={({ field, form }) => {
          return (
            <input
              type="checkbox"
              id={id}
              className={className}
              checked={field.value}
              {...field}
            />
          );
        }}
      />
    </>
  );
}

I only used for a single true/false value, so your mileage may vary if you're working on something else.

I extracted the code above from this CodeSandbox, so please check it out. I think it'll show you how to do a little more than my implementation does.

It looks like the checkbox issue will be fixed in version 2 of Formik according to its author Jared Palmer, but this should be a workable solution until then.

Top comments (4)

Alex Whinfield • Feb 8 '20

Working great thank you, I'm using it with TypeScript so here is my component for anybody that may be interested.

import React from "react";
import { Field, FieldProps } from "formik";

interface Props {
  id: string;
  name: string;
  className: string;
}

export const Checkbox = ({ id, name, className }: Props): JSX.Element => (
  <Field
    name={name}
    render={({ field }: FieldProps) => (
      <input
        id={id}
        {...field}
        type="checkbox"
        className={className}
        checked={field.value}
      />
    )}
  />
);