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Version: Next

Using redux state

Creating states#

Lets create a new state in the redux store at the path named todos with initial values of array { 1: {done: false}, 2: {done: true}, 3: {done: false} }.

import {useReduxState} from 'use-redux-states'
const App = () => {
useReduxState({
path: 'todos',
state: {
1: {done: false},
2: {done: true},
3: {done: false}
},
})
// creates state in the store with key = todos and value = {
// 1: {done: false},
// 2: {done: true},
// 3: {done: false}
// }
}

Controlling how initial state should be set#

When you use the redux-state-hook with a default state, under the hood it sets the initial state in the store with the given path.
redux-state-hook has an intelligent setter function which determines how your state will be set based on the payload (referring the initial state as the payload). When array is passed as the payload setter assumes you will append the payload with the current state array.
Given the example below the initial todos state has [{done: false}, {done: true}, {done: false}] value, setter will push to the existing array state if the payload is array otherwise will replace the state.

import React from 'react'
import useReduxState from 'use-redux-states'
const App = () => {
// existing todos state = [{done: false}, {done: true}, {done: false}]
useReduxState({
path: 'todos',
state: [
{done: false},
{done: true},
{done: false}
],
})
// later todos state = [
// {done: false},
// {done: true},
// {done: false}
// ]
}

Same logic applies to json object but primitive payload value replaces the existing state.
You can handle the setter behaviour by passing a reducer function.

import React from 'react'
import useReduxState from 'use-redux-states'
const App = () => {
// existing todos state = [{done: false}, {done: true}, {done: false}]
useReduxState({
path: 'todos',
state: [{done: true}],
reducer: (existingState, payload) => existingState ? [...payload, ...existingState] : payload
// custom setter function prepends to the existing state
})
// later todos state = [{done: true}, {done: false}, {done: true}, {done: false}]
}

Retrieving state#

Lets retrieve the new state we have created using getState.

import {useReduxState} from 'use-redux-states'
const App = () => {
const {getState} = useReduxState({
path: 'todos',
state: {
1: {done: false},
2: {done: true},
3: {done: false}
},
})
console.log(getState()) // {
// 1: {done: false},
// 2: {done: true},
// 3: {done: false}
// }
}

Reactively getting state#

We can retrieve states reactively using useStateSelector or useGetState hooks.

import {useReduxState, useGetState} from 'use-redux-states'
const App = () => {
const {useStateSelector} = useReduxState({
path: 'todos',
state: {
1: {done: false},
2: {done: true},
3: {done: false}
},
})
const todos = useStateSelector()
console.log(todos) // {
// 1: {done: false},
// 2: {done: true},
// 3: {done: false}
// }
}

Getting already existing states#

In some cases we might want to get an already existsing state without using the useReduxState.

import {useGetState} from 'use-redux-states'
const App = () => {
const getTodos = useGetState('todos')
const todos = getTodos()
console.log(todos) // {
// 1: {done: false},
// 2: {done: true},
// 3: {done: false}
// }
}

Reactively getting already existing states#

We can reactively get already existsing state without using the useReduxState.

import {useMemoSelector} from 'use-redux-states'
const App = () => {
const todo = useMemoSelector('todos.2')
console.log(todo) // {done: true},
}

Retrieving computed state with callback#

We can retrieve and compute states by passing callback function to useStateSelector hook and or getState.

import {useReduxState} from 'use-redux-states'
const App = () => {
const {useStateSelector, getState} = useReduxState({
path: 'todos',
state: {
1: {done: false},
2: {done: true},
3: {done: false}
},
})
const todo = useStateSelector((todos) => todos[0])
const todo2 = getState((todos) => todos[1])
console.log(todo, todo2) // {done: false},{done: false}
}

Updating states#

We can update states with setState.

import {useReduxState} from 'use-redux-states'
const App = () => {
const {setState, getState} = useReduxState({
path: 'todos',
state: {
1: {done: false},
2: {done: true},
3: {done: false}
},
})
const makeTodo3Done = () => setState({3: {done: true}})
makeTodo3Done();
console.log(getState()) // {
// 1: {done: false},
// 2: {done: true},
// 3: {done: true}
// }
}

Updating states with setter callback#

We can also update states by passing a custom setter to setState.

import {useReduxState} from 'use-redux-states'
const App = () => {
const {setState, getState} = useReduxState({
path: 'todos',
state: {
1: {done: false},
2: {done: true},
3: {done: false}
},
})
const makeTodo3Done = () => setState((todos) => {
todos.[3].done = true;
return todos
})
makeTodo3Done();
console.log(getState()) // {
// 1: {done: false},
// 2: {done: true},
// 3: {done: true}
// }
}

Updating already existing states#

We can update already existing states with useSetState hook.

import {useSetState, useGetState} from 'use-redux-states'
const App = () => {
const updateThirdTodo = useSetState('todos.3')
const getTodos = useGetState('todos')
const makeTodoDone = () => updateThirdTodo({done: true})
makeTodoDone();
console.log(getTodos()) // {
// 1: {done: false},
// 2: {done: true},
// 3: {done: true}
// }
}

Updating already existing states#

We can update already existing states with useSetState hook.

import {useSetState, useGetState} from 'use-redux-states'
const App = () => {
const updateThirdTodo = useSetState('todos.3')
const getTodos = useGetState('todos')
const makeTodoDone = () => updateThirdTodo((todo3) => {
todo3.done = true;
return todo3
})
makeTodoDone();
console.log(getTodos()) // {
// 1: {done: false},
// 2: {done: true},
// 3: {done: true}
// }
}
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