Files
xyflow/packages/react/src/hooks/useOnSelectionChange.ts
2025-04-09 10:36:16 +02:00

62 lines
2.0 KiB
TypeScript

import { useEffect } from 'react';
import { useStoreApi } from './useStore';
import type { OnSelectionChangeFunc, Node, Edge } from '../types';
export type UseOnSelectionChangeOptions<NodeType extends Node = Node, EdgeType extends Edge = Edge> = {
/** The handler to register. */
onChange: OnSelectionChangeFunc<NodeType, EdgeType>;
};
/**
* This hook lets you listen for changes to both node and edge selection. As the
*name implies, the callback you provide will be called whenever the selection of
*_either_ nodes or edges changes.
*
* @public
* @example
* ```jsx
*import { useState } from 'react';
*import { ReactFlow, useOnSelectionChange } from '@xyflow/react';
*
*function SelectionDisplay() {
* const [selectedNodes, setSelectedNodes] = useState([]);
* const [selectedEdges, setSelectedEdges] = useState([]);
*
* // the passed handler has to be memoized, otherwise the hook will not work correctly
* const onChange = useCallback(({ nodes, edges }) => {
* setSelectedNodes(nodes.map((node) => node.id));
* setSelectedEdges(edges.map((edge) => edge.id));
* }, []);
*
* useOnSelectionChange({
* onChange,
* });
*
* return (
* <div>
* <p>Selected nodes: {selectedNodes.join(', ')}</p>
* <p>Selected edges: {selectedEdges.join(', ')}</p>
* </div>
* );
*}
*```
*
* @remarks You need to memoize the passed `onChange` handler, otherwise the hook will not work correctly.
*/
export function useOnSelectionChange<NodeType extends Node = Node, EdgeType extends Edge = Edge>({
onChange,
}: UseOnSelectionChangeOptions<NodeType, EdgeType>) {
const store = useStoreApi<NodeType, EdgeType>();
useEffect(() => {
const nextOnSelectionChangeHandlers = [...store.getState().onSelectionChangeHandlers, onChange];
store.setState({ onSelectionChangeHandlers: nextOnSelectionChangeHandlers });
return () => {
const nextHandlers = store.getState().onSelectionChangeHandlers.filter((fn) => fn !== onChange);
store.setState({ onSelectionChangeHandlers: nextHandlers });
};
}, [onChange]);
}