useReactFlow

This example illustrates how to use the useReactFlow hook. It comes with a lot of useful helpers to update your nodes and edges or adjust the viewport of your diagram. The hook returns a ReactFlow instance.


import React, { useCallback } from 'react';
import {
  Background,
  ReactFlow,
  ReactFlowProvider,
  addEdge,
  useNodesState,
  useEdgesState,
} from '@xyflow/react';
 
import Buttons from './Buttons';
import '@xyflow/react/dist/style.css';
 
const initialNodes = [
  {
    id: '1',
    type: 'input',
    data: { label: 'Node 1' },
    position: { x: 250, y: 5 },
  },
  { id: '2', data: { label: 'Node 2' }, position: { x: 100, y: 100 } },
  { id: '3', data: { label: 'Node 3' }, position: { x: 400, y: 100 } },
  { id: '4', data: { label: 'Node 4' }, position: { x: 400, y: 200 } },
];
 
const initialEdges = [
  {
    id: 'e1-2',
    source: '1',
    target: '2',
  },
  { id: 'e1-3', source: '1', target: '3' },
];
 
const ProviderFlow = () => {
  const [nodes, , onNodesChange] = useNodesState(initialNodes);
  const [edges, setEdges, onEdgesChange] = useEdgesState(initialEdges);
  const onConnect = useCallback(
    (params) => setEdges((els) => addEdge(params, els)),
    [],
  );
 
  return (
    <ReactFlowProvider>
      <ReactFlow
        nodes={nodes}
        edges={edges}
        onNodesChange={onNodesChange}
        onEdgesChange={onEdgesChange}
        onConnect={onConnect}
        fitView
      >
        <Buttons />
        <Background />
      </ReactFlow>
    </ReactFlowProvider>
  );
};
 
export default ProviderFlow;