`useIndexes`

The useIndexes hook is used to get a reference to an Indexes object from within a Provider component context.

useIndexes(id?: string): Indexes | undefined

Type Description

	Type	Description
`id?`	`string`	An optional `Id` for accessing an `Indexes` object that was named with an `Id` in the Provider.
returns	`Indexes \| undefined`	A reference to the `Indexes` object (or `undefined` if not within a Provider context, or if the requested `Indexes` object does not exist).

id?

string

An optional Id for accessing an Indexes object that was named with an Id in the Provider.

returns

Indexes | undefined

A reference to the Indexes object (or undefined if not within a Provider context, or if the requested Indexes object does not exist).

A Provider component is used to wrap part of an application in a context. It can contain a default Indexes object (or a set of Indexes objects named by Id) that can be easily accessed without having to be passed down as props through every component.

The useIndexes hook lets you either get a reference to the default Indexes object (when called without a parameter), or one of the Indexes objects that are named by Id (when called with an Id parameter).

Examples

This example creates a Provider context into which a default Indexes object is provided. A component within it then uses the useIndexes hook to get a reference to the Indexes object again, without the need to have it passed as a prop.

import React from 'react';
import {createRoot} from 'react-dom/client';
import {createIndexes, createStore} from 'tinybase';
import {Provider, useIndexes} from 'tinybase/ui-react';

const App = ({indexes}) => (
  <Provider indexes={indexes}>
    <Pane />
  </Provider>
);
const Pane = () => <span>{useIndexes().getListenerStats().sliceIds}</span>;

const indexes = createIndexes(createStore());
const app = document.createElement('div');
createRoot(app).render(<App indexes={indexes} />);
console.log(app.innerHTML);
// -> '<span>0</span>'

This example creates a Provider context into which an Indexes object is provided, named by Id. A component within it then uses the useIndexes hook with that Id to get a reference to the Indexes object again, without the need to have it passed as a prop.

import React from 'react';
import {createRoot} from 'react-dom/client';
import {createIndexes, createStore} from 'tinybase';
import {Provider, useIndexes} from 'tinybase/ui-react';

const App = ({indexes}) => (
  <Provider indexesById={{petStore: indexes}}>
    <Pane />
  </Provider>
);
const Pane = () => (
  <span>{useIndexes('petStore').getListenerStats().sliceIds}</span>
);

const indexes = createIndexes(createStore());
const app = document.createElement('div');
createRoot(app).render(<App indexes={indexes} />);
console.log(app.innerHTML);
// -> '<span>0</span>'

Since

v1.0.0