redux
How to use actions and reducers in a store
redux
middleware lets you update a store through actions and reducers just like redux.
const nextStateCreatorFn = redux(reducerFn, initialState)
Types
Signature
redux<T, A>(reducerFn: (state: T, action: A) => T, initialState: T): StateCreator<T & { dispatch: (action: A) => A }, [['zustand/redux', A]], []>
Mutator
['zustand/redux', A]
Reference
redux(reducerFn, initialState)
Parameters
reducerFn
: It should be pure and should take the current state of your application and an action object as arguments, and returns the new state resulting from applying the action.initialState
: The value you want the state to be initially. It can be a value of any type, except a function.
Returns
redux
returns a state creator function.
Usage
Updating state through actions and reducers
import { createStore } from 'zustand/vanilla'
import { redux } from 'zustand/middleware'
type PersonStoreState = {
firstName: string
lastName: string
email: string
}
type PersonStoreAction =
| { type: 'person/setFirstName'; firstName: string }
| { type: 'person/setLastName'; lastName: string }
| { type: 'person/setEmail'; email: string }
type PersonStore = PersonStoreState & PersonStoreActions
const personStoreReducer = (
state: PersonStoreState,
action: PersonStoreAction,
) => {
switch (action.type) {
case 'person/setFirstName': {
return { ...state, firstName: action.firstName }
}
case 'person/setLastName': {
return { ...state, lastName: action.lastName }
}
case 'person/setEmail': {
return { ...state, email: action.email }
}
default: {
return state
}
}
}
const personStoreInitialState: PersonStoreState = {
firstName: 'Barbara',
lastName: 'Hepworth',
email: 'bhepworth@sculpture.com',
}
const personStore = createStore<PersonStore>()(
redux(personStoreReducer, personStoreInitialState),
)
const $firstNameInput = document.getElementById(
'first-name',
) as HTMLInputElement
const $lastNameInput = document.getElementById('last-name') as HTMLInputElement
const $emailInput = document.getElementById('email') as HTMLInputElement
const $result = document.getElementById('result') as HTMLDivElement
function handleFirstNameChange(event: Event) {
personStore.dispatch({
type: 'person/setFirstName',
firstName: (event.target as any).value,
})
}
function handleLastNameChange(event: Event) {
personStore.dispatch({
type: 'person/setLastName',
lastName: (event.target as any).value,
})
}
function handleEmailChange(event: Event) {
personStore.dispatch({
type: 'person/setEmail',
email: (event.target as any).value,
})
}
$firstNameInput.addEventListener('input', handleFirstNameChange)
$lastNameInput.addEventListener('input', handleLastNameChange)
$emailInput.addEventListener('input', handleEmailChange)
const render: Parameters<typeof personStore.subscribe>[0] = (person) => {
$firstNameInput.value = person.firstName
$lastNameInput.value = person.lastName
$emailInput.value = person.email
$result.innerHTML = `${person.firstName} ${person.lastName} (${person.email})`
}
render(personStore.getInitialState(), personStore.getInitialState())
personStore.subscribe(render)
Here's the html
code
<label style="display: block">
First name:
<input id="first-name" />
</label>
<label style="display: block">
Last name:
<input id="last-name" />
</label>
<label style="display: block">
Email:
<input id="email" />
</label>
<p id="result"></p>
Troubleshooting
TBD