getting setstate to cause a rerender every time in a useEffect block - reactjs

Question

I've created this codesandbox example and here is the code:
import React, { ReactNode, useState } from "react";
import { Formik, FormikConfig, FormikProps, Form, FormikErrors } from "formik";
import { useEffect } from "react";
import { scrollToValidationError } from "./scrollToValidationError";
// const isEmpty = (a: unknown): boolean =>
// typeof a === "object" && Object.keys(a).length > 0;
export type FormContainerProps<V> = {
render({
values,
errors,
invalid,
submitCount,
isSubmitting
}: {
values: V;
invalid: boolean;
errors: FormikErrors<V>;
submitCount: number;
isSubmitting: boolean;
}): ReactNode;
additionalContent?: ReactNode;
nextButtonText?: string;
} & Pick<FormikConfig<V>, "initialValues" | "validate"> &
Partial<Pick<FormikConfig<V>, "onSubmit">>;
export const FormContainer = function FormContainer<V>({
initialValues,
additionalContent,
validate,
render,
...rest
}: FormContainerProps<V>) {
const [hasValidationError, setHasValidationError] = useState(false);
useEffect(() => {
if (!hasValidationError) {
return;
}
scrollToValidationError();
}, [hasValidationError]);
return (
<>
<Formik
initialValues={initialValues}
validate={validate}
onSubmit={async (values, { validateForm }) => {}}
>
{({
isSubmitting,
submitCount,
isValid,
errors,
values
}: FormikProps<V>) => {
const invalid = !isValid;
if (submitCount > 0 && invalid) {
setHasValidationError(true);
}
return (
<>
<div data-selector="validation-summary">Validation Summary</div>
<Form>
<div>
<div>
{render({
values,
errors,
isSubmitting,
invalid,
submitCount
})}
</div>
<div>
<button type="submit">SUBMIT</button>
</div>
</div>
</Form>
</>
);
}}
</Formik>
</>
);
};
Basically I am calling setHasValidationError(true) which breaks the dependency watcher on useEffect
useEffect(() => {
if (!hasValidationError) {
return;
}
scrollToValidationError();
setTimeout(() => setHasValidationError(false));
}, [hasValidationError]);
But if this is a form with multiple errors then I want to trigger the useEffect every time but I don't know when to reset it to false or if there is a better way.

Answer 1

In order to scroll to the first error field upon clicking on submit then you can do the following:
Write a custom component (eg: FocuseabelField) that renders formik field which also handles automatic scroll to element and focus on error input
Use Formik's innerRef
Just use the formik's isSubmitting and errors to handle logic for scrolling and focussing
FocuseabelField custom component
const FocuseabelField: any = props => {
const elementRef = useRef<HTMLDivElement>();
if (
props.isSubmitting &&
elementRef.current !== undefined &&
props.errors.hasOwnProperty(props.name)
) {
elementRef.current.scrollIntoView();
elementRef.current.focus();
}
return <Field {...props} innerRef={elementRef} />;
};
Usage
<FocuseabelField
errors={errors}
isSubmitting={isSubmitting}
name="name"
placeholder="enter name"
className={errors && errors.name ? "input error" : "input"}
/>
I have taken your code and have commented the stuff like scrollToValidationerror.ts, dom.ts, wait.ts, useState(hasValidationError), useEffect etc.
Simplified working copy of the code is here. I have used 2 fields to demonstrate multiple errors & auto scroll & focus to the error field:
https://codesandbox.io/s/usemachine-typescript-problems-tns0c?file=/src/components/Home/index.tsx
When the forms gets bigger it becomes complicated to manage so its good to consider outsourcing the form validation part and use libraries such as yup and maintain a validation schema and pass it on to formik.
Have a look at the formik docs for examples.

Answer 2

What about creating an Object with keys for each form field? That way you can maintain a specific form validation error for each input and use that Object in the useEffect second parameter, it will make sure it's triggered for each form error update

Answer 3

To answer your original question,
useEffect does reference check for its dependencies, so you could use Object instead of value. So something like this.
const [hasValidationError, setHasValidationError] = useState({value: false});
useEffect(() => {
if (!hasValidationError.value) {
return;
}
scrollToValidationError();
}, [hasValidationError]);
setHasValidationError({value: true});
But in regards to Formik usage, I highly recommend you follow what #gdh pointed out.

Answer 4

I don't understand the need of effects here.
Why don't you call the method directly instead of using hooks?
You can avoid 2 re-renders by doing that, and the component can also be stateless!
...
}: FormikProps<V>) => {
const invalid = !isValid;
if (submitCount > 0 && invalid) {
scrollToValidationError();
}
...