React hooks - state in useState() is not reset when route is changed

Question

const Create = () => {
  console.log('rerender !!')
  const [parcelType, setParcelType] = useState('paper')
  console.log('parcelType =', parcelType)

  return (
    <Container onClick={() => setParcelType('plastic')}>
      <BookingList />
      <Card title="Business">
        <p>Header</p>
      </Card>
    </Container>
  )
}

export default Create

I want to change parcelType state to 'plastic' when click on Container in Create component. and I want to reset parcelType state to 'paper' when route is change ( Create component re-render ). But when component re-render state is not set to paper

For more details: CreateComponent is re-render when route is change in BookingList component

 const BookingList = props => {
  const { id } = props.match.params
  const containerStyle = useTranslateSpring('-100px', '0')

  const itemList = items.map((item, idx) => {
    const itemStyle = useTranslateSpring('-100px', '0', '0', 200 + 200 * idx)
    const url = `/booking/${item.id}/create`

    return (
      <ItemContainer
        onClick={() => props.history.push(url)}
        style={itemStyle}
        key={item.id}
        isactive={id === item.id}
      >
        {item.id}
      </ItemContainer>
    )
  })
  return <Container style={containerStyle}>{itemList}</Container>
}

export default withRouter(BookingList)

Create Component is render in route by routeTemplate

const Routes = () => (
 <Router basename={process.env.REACT_APP_BASE_URL}>
   <> 
    <RouteTemplate
    exact
    path="/booking/:id/create"
    component={Booking.create}
    title="Booking"
    />
   </>
 </Router>
)

and RouteTemplate is render Component wrapped by PageTemplate component

  const RouteTemplate = props => {
  const {
    component: Component,
    title,
    query,
    isAuthenticated,
    isLanding,
    ...rest
  } = props

  return (
    <Route
      {...rest}
      render={matchProps =>
        isAuthenticated ? (
          <PageTemplate title={title} isLanding={isLanding}>
            <Component {...matchProps} query={query} />
          </PageTemplate>
        ) : (
          <Redirect
            to={{
              pathname: '/',
              state: { from: props.location },
            }}
          />
        )
      }
    />
  )
}

Answer 1

So I assume you want to reset component's state once route is changed.

This should happen wherever you use functional component + hooks or class-based component with explicit this.state. It's how React works under the hood.

1. You already have <Create> rendered at the page
2. Once route is changed <Route> tries to render <Create> element
3. React sees there is already existing <Create> element and tries to update that instead of re-creating(typically update is much more efficient than re-creating). That's why state is not reset - since it should not reset for updates.

There are different way to handle that.

If such a case happen outside react-router's <Route> I'd suggest use key prop to reset state. But for <Route> it would mean replacing more clear/straightforward <Route path="..." component={Create} /> with more verboose <Route path="..." render={({match}) => <Create match={match} key={match.params.id} />}

So instead let's apply useEffect hook to reset state once props.match.params.id is changed:

const Create = ({ match: {params: {id} } }) => {    

  useEffect(() => {
    setParcelType('paper');
  }, [id]);

That should be equal to class-based

state = {
  typeOfWhatEver: 'paper'
};

componentDidUpdate(prevProps) {
  if(prevProps.match.params.id !== this.props.match.params.id) {
    this.setState({
      typeOfWhatEver: 'paper'
    });
  }
}