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ra-core

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Core components of react-admin, a frontend Framework for building admin applications on top of REST services, using ES6, React

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import { useState, useEffect } from 'react'; import isEqual from 'lodash/isEqual'; import { useEvent } from '../util'; import { useStoreContext } from './useStoreContext'; /** * Read and write a value from the Store * * useState-like hook using the global Store for persistence. * Each time a store value is changed, all components using this value will be re-rendered. * * @param {string} key Name of the store key. Separate with dots to namespace, e.g. 'posts.list.columns'. * @param {any} defaultValue Default value * * @return {Object} A value and a setter for the value, in an array - just like for useState() * * @example * import { useStore } from 'react-admin'; * * const PostList = () => { * const [density] = useStore('posts.list.density', 'small'); * * return ( * <List> * <Datagrid size={density}> * ... * </Datagrid> * </List> * ); * } * * // Clicking on this button will trigger a rerender of the PostList! * const ChangeDensity: FC<any> = () => { * const [density, setDensity] = useStore('posts.list.density', 'small'); * * const changeDensity = (): void => { * setDensity(density === 'small' ? 'medium' : 'small'); * }; * * return ( * <Button onClick={changeDensity}> * {`Change density (current ${density})`} * </Button> * ); * }; */ export var useStore = function (key, defaultValue) { var _a = useStoreContext(), getItem = _a.getItem, setItem = _a.setItem, subscribe = _a.subscribe; var _b = useState(function () { return getItem(key, defaultValue); }), value = _b[0], setValue = _b[1]; // subscribe to changes on this key, and change the state when they happen useEffect(function () { var storedValue = getItem(key, defaultValue); if (!isEqual(value, storedValue)) { setValue(storedValue); } var unsubscribe = subscribe(key, function (newValue) { setValue(typeof newValue === 'undefined' ? defaultValue : newValue); }); return function () { return unsubscribe(); }; }, [key, subscribe, defaultValue, getItem, value]); var set = useEvent(function (valueParam, runtimeDefaultValue) { var newValue = typeof valueParam === 'function' ? valueParam(value) : valueParam; // we only set the value in the Store; // the value in the local state will be updated // by the useEffect during the next render setItem(key, typeof newValue === 'undefined' ? typeof runtimeDefaultValue === 'undefined' ? defaultValue : runtimeDefaultValue : newValue); }); return [value, set]; }; //# sourceMappingURL=useStore.js.map