feat(nested-nodes): callback for parent node size change

example/src/Basic/index.tsx

@@ -1,4 +1,4 @@
-import { useState, MouseEvent, useCallback } from 'react';
+import { useState, useMemo, MouseEvent, useCallback } from 'react';
 
 import ReactFlow, {
   addEdge,
@@ -26,21 +26,23 @@ const initialNodes: Node[] = [
   {
     id: '4',
     data: { label: 'Node 4' },
-    position: { x: 400, y: 200 },
+    position: { x: 0, y: 0 },
     className: 'light',
     style: { backgroundColor: 'rgba(255, 0, 0, .2)' },
+    width: 0,
+    height: 0,
   },
   {
     id: '4a',
     data: { label: 'Node 4a' },
-    position: { x: 400, y: 400 },
+    position: { x: 70, y: 200 },
     className: 'light',
     parentNode: '4',
   },
   {
     id: '4b',
     data: { label: 'Node 4b' },
-    position: { x: 500, y: 500 },
+    position: { x: 0, y: 0 },
     className: 'light',
     style: { backgroundColor: 'rgba(255, 0, 0, .2)' },
     parentNode: '4',
@@ -48,14 +50,14 @@ const initialNodes: Node[] = [
   {
     id: '4b1',
     data: { label: 'Node 4b1' },
-    position: { x: 450, y: 450 },
+    position: { x: 150, y: 270 },
     className: 'light',
     parentNode: '4b',
   },
   {
     id: '4b2',
     data: { label: 'Node 4b2' },
-    position: { x: 550, y: 550 },
+    position: { x: 420, y: 370 },
     className: 'light',
     parentNode: '4b',
   },
@@ -64,6 +66,13 @@ const initialNodes: Node[] = [
 const initialEdges: Edge[] = [
   { id: 'e1-2', source: '1', target: '2', animated: true },
   { id: 'e1-3', source: '1', target: '3' },
+  { id: 'e2-4a', source: '2', target: '4a', animated: true },
+  { id: 'e3-4', source: '3', target: '4' },
+  { id: 'e3-4b', source: '3', target: '4b' },
+  { id: 'e3-4b2', source: '3', target: '4b2' },
+  { id: 'e4a-4b1', source: '4a', target: '4b1' },
+  { id: 'e4a-4b2', source: '4a', target: '4b2' },
+  { id: 'e4b1-4b2', source: '4b1', target: '4b2' },
 ];
 
 const BasicFlow = () => {
@@ -120,9 +129,18 @@ const BasicFlow = () => {
     setEdges((es) => applyEdgeChanges(changes, es));
   }, []);
 
+  const nodesWithLabel = useMemo(
+    () =>
+      nodes.map((n) => {
+        n.data = { ...n.data, label: `${n.width}x${n.height}` };
+        return n;
+      }),
+    [nodes]
+  );
+
   return (
     <ReactFlow
-      nodes={nodes}
+      nodes={nodesWithLabel}
       edges={edges}
       onLoad={onLoad}
       onNodesChange={onNodesChange}

src/container/NodeRenderer/index.tsx

@@ -1,4 +1,4 @@
-import React, { memo, useMemo, ComponentType, MouseEvent, Fragment } from 'react';
+import React, { memo, useMemo, ComponentType, MouseEvent, Fragment, useEffect } from 'react';
 import shallow from 'zustand/shallow';
 
 import { useStore } from '../../store';
@@ -44,9 +44,16 @@ interface NodesProps extends NodeRendererProps {
   parentId?: string;
 }
 
-function Nodes({
+interface NodeProps extends NodesProps {
+  nodes: Node[];
+  node: Node;
+  nodeType: string;
+}
+
+function Node({
   nodes,
-  parentId,
+  node,
+  nodeType,
   isDraggable,
   resizeObserver,
   scale,
@@ -57,19 +64,8 @@ function Nodes({
   elementsSelectable,
   recursionDepth,
   ...props
-}: NodesProps): any {
-  const rootNodes = useMemo(
-    () => (parentId ? nodes.filter((n) => n.parentNode === parentId) : nodes.filter((n) => !n.parentNode)),
-    [nodes, parentId]
-  );
-
-  return rootNodes.map((node) => {
-    const nodeType = node.type || 'default';
-
-    if (!props.nodeTypes[nodeType]) {
-      console.warn(`Node type "${nodeType}" not found. Using fallback type "default".`);
-    }
-
+}: NodeProps) {
+  const onNodesChange = useStore((s) => s.onNodesChange);
   const NodeComponent = (props.nodeTypes[nodeType] || props.nodeTypes.default) as ComponentType<WrapNodeProps>;
   const isNodeDraggable =
     typeof isDraggable !== 'undefined'
@@ -83,23 +79,35 @@ function Nodes({
     typeof node.width !== 'undefined' &&
     typeof node.height !== 'undefined';
 
-    const childNodes = nodes.filter((n) => n.parentNode === node.id && !n.isHidden);
+  const childNodes = useMemo(() => nodes.filter((n) => n.parentNode === node.id && !n.isHidden), [nodes, node.id]);
+  const childRect = useMemo(() => getRectOfNodes(childNodes), [childNodes]);
+  const isParentNode = !!childNodes.length;
 
-    if (childNodes.length) {
-      const childRect = getRectOfNodes(childNodes);
-      node.position = node.isDragging
-        ? node.position
-        : { x: Math.round(childRect.x) - 10, y: Math.round(childRect.y) - 10 };
-      node.style = {
+  node.style = useMemo(() => {
+    if (isParentNode) {
+      return {
         ...node.style,
-        width: Math.round(childRect.width) + 20,
-        height: Math.round(childRect.height) + 20,
+        width: Math.floor(childRect.width) + 20,
+        height: Math.floor(childRect.height) + 20,
         boxSizing: 'border-box',
       };
     }
+    return node.style;
+  }, [childRect.width, childRect.height, isParentNode, node.style]);
+
+  useEffect(() => {
+    if (onNodesChange && isParentNode) {
+      onNodesChange([
+        {
+          type: 'position',
+          id: node.id,
+          position: { x: Math.floor(childRect.x) - 10, y: Math.floor(childRect.y) - 10 },
+        },
+      ]);
+    }
+  }, [childRect.width, childRect.height, childRect.x, childRect.y, isParentNode]);
 
   return (
-      <Fragment key={node.id}>
     <NodeComponent
       id={node.id}
       className={node.className}
@@ -130,10 +138,56 @@ function Nodes({
       isDraggable={isNodeDraggable}
       isSelectable={isSelectable}
       isConnectable={isConnectable}
-          resizeObserver={childNodes.length ? resizeObserver : null}
+      resizeObserver={resizeObserver}
       dragHandle={node.dragHandle}
       zIndex={3 + recursionDepth}
     />
+  );
+}
+
+function Nodes({
+  nodes,
+  parentId,
+  isDraggable,
+  resizeObserver,
+  scale,
+  snapToGrid,
+  snapGrid,
+  nodesDraggable,
+  nodesConnectable,
+  elementsSelectable,
+  recursionDepth,
+  ...props
+}: NodesProps): any {
+  const rootNodes = useMemo(
+    () => (parentId ? nodes.filter((n) => n.parentNode === parentId) : nodes.filter((n) => !n.parentNode)),
+    [nodes, parentId]
+  );
+
+  return rootNodes.map((node) => {
+    const nodeType = node.type || 'default';
+
+    if (!props.nodeTypes[nodeType]) {
+      console.warn(`Node type "${nodeType}" not found. Using fallback type "default".`);
+    }
+
+    return (
+      <Fragment key={node.id}>
+        <Node
+          node={node}
+          nodes={nodes}
+          nodeType={nodeType}
+          parentId={node.id}
+          snapToGrid={snapToGrid}
+          snapGrid={snapGrid}
+          nodesDraggable={nodesDraggable}
+          nodesConnectable={nodesConnectable}
+          resizeObserver={resizeObserver}
+          elementsSelectable={elementsSelectable}
+          scale={scale}
+          recursionDepth={recursionDepth}
+          {...props}
+        />
         <MemoizedNodes
           nodes={nodes}
           parentId={node.id}