Files
xyflow/packages/react/src/hooks/useStore.ts
2025-02-11 13:59:17 +01:00

77 lines
2.3 KiB
TypeScript

import { useContext, useMemo } from 'react';
import { UseBoundStoreWithEqualityFn, useStoreWithEqualityFn as useZustandStore } from 'zustand/traditional';
import { StoreApi } from 'zustand';
import { errorMessages } from '@xyflow/system';
import StoreContext from '../contexts/StoreContext';
import type { Edge, Node, ReactFlowState } from '../types';
const zustandErrorMessage = errorMessages['error001']();
/**
* This hook can be used to subscribe to internal state changes of the React Flow
*component. The `useStore` hook is re-exported from the [Zustand](https://github.com/pmndrs/zustand)
*state management library, so you should check out their docs for more details.
*
* @public
* @param selector
* @param equalityFn
* @returns The selected state slice
*
* @example
* ```ts
* const nodes = useStore((state) => state.nodes);
* ```
*
* @remarks This hook should only be used if there is no other way to access the internal
*state. For many of the common use cases, there are dedicated hooks available
*such as {@link useReactFlow}, {@link useViewport}, etc.
*/
function useStore<StateSlice = unknown>(
selector: (state: ReactFlowState) => StateSlice,
equalityFn?: (a: StateSlice, b: StateSlice) => boolean
) {
const store = useContext(StoreContext);
if (store === null) {
throw new Error(zustandErrorMessage);
}
return useZustandStore(store, selector, equalityFn);
}
/**
* In some cases, you might need to access the store directly. This hook returns the store object which can be used on demand to access the state or dispatch actions.
*
* @returns The store object
*
* @example
* ```ts
* const store = useStoreApi();
* ```
*
* @remarks This hook should only be used if there is no other way to access the internal
*state. For many of the common use cases, there are dedicated hooks available
*such as {@link useReactFlow}, {@link useViewport}, etc.
*/
function useStoreApi<NodeType extends Node = Node, EdgeType extends Edge = Edge>() {
const store = useContext(StoreContext) as UseBoundStoreWithEqualityFn<
StoreApi<ReactFlowState<NodeType, EdgeType>>
> | null;
if (store === null) {
throw new Error(zustandErrorMessage);
}
return useMemo(
() => ({
getState: store.getState,
setState: store.setState,
subscribe: store.subscribe,
}),
[store]
);
}
export { useStore, useStoreApi };