React Diagram - Editing Restrictions

import React, { useCallback, useRef } from 'react'; import Diagram, { CustomShape, Nodes, AutoLayout, ContextToolbox, Toolbox, PropertiesPanel, Group, DiagramTypes, } from 'devextreme-react/diagram'; import notify from 'devextreme/ui/notify'; import ArrayStore from 'devextreme/data/array_store'; import service from './data.ts'; const shapes = ['team', 'employee']; const orgItemsDataSource = new ArrayStore({ key: 'ID', data: service.getOrgItems(), }); function showToast(text: string) { notify({ position: { at: 'top', my: 'top', of: '#diagram', offset: '0 4', }, message: text, type: 'warning', delayTime: 2000, }); } function onRequestLayoutUpdate(e: DiagramTypes.RequestLayoutUpdateEvent) { for (let i = 0; i < e.changes.length; i += 1) { if (e.changes[i].type === 'remove') { e.allowed = true; } else if (e.changes[i].data.ParentID !== undefined && e.changes[i].data.ParentID !== null) { e.allowed = true; } } } function itemStyleExpr(obj: { Type: string; }) { if (obj.Type === 'root') { return { fill: '#ffcfc3' }; } if (obj.Type === 'team') { return { fill: '#b7e3fe' }; } return { fill: '#bbefcb' }; } export default function App() { const diagramRef = useRef(null); const onRequestEditOperation = useCallback((e) => { const diagram = diagramRef.current.instance(); if (e.operation === 'addShape') { if (e.args.shape.type !== 'employee' && e.args.shape.type !== 'team') { if (e.reason !== 'checkUIElementAvailability') { showToast('You can add only a \'Team\' or \'Employee\' shape.'); } e.allowed = false; } } else if (e.operation === 'deleteShape') { if (e.args.shape.type === 'root') { if (e.reason !== 'checkUIElementAvailability') { showToast('You cannot delete the \'Development\' shape.'); } e.allowed = false; } if (e.args.shape.type === 'team') { for (let i = 0; i < e.args.shape.attachedConnectorIds.length; i += 1) { if (diagram.getItemById(e.args.shape.attachedConnectorIds[i]).toId !== e.args.shape.id) { if (e.reason !== 'checkUIElementAvailability') { showToast('You cannot delete a \'Team\' shape that has a child shape.'); } e.allowed = false; break; } } } } else if (e.operation === 'resizeShape') { if (e.args.newSize.width < 1 || e.args.newSize.height < 0.75) { if (e.reason !== 'checkUIElementAvailability') { showToast('The shape size is too small.'); } e.allowed = false; } } else if (e.operation === 'changeConnection') { const shapeType = e.args.newShape && e.args.newShape.type; if (shapeType === 'root' && e.args.connectorPosition === 'end') { if (e.reason !== 'checkUIElementAvailability') { showToast('The \'Development\' shape cannot have an incoming connection.'); } e.allowed = false; } if (shapeType === 'employee' && e.args.connectorPosition === 'start') { e.allowed = false; } } else if (e.operation === 'changeConnectorPoints') { if (e.args.newPoints.length > 2) { if (e.reason !== 'checkUIElementAvailability') { showToast('You cannot add points to a connector.'); } e.allowed = false; } } else if (e.operation === 'beforeChangeShapeText') { if (e.args.shape.type === 'root') { if (e.reason !== 'checkUIElementAvailability') { showToast('You cannot change the \'Development\' shape\'s text.'); } e.allowed = false; } } else if (e.operation === 'changeShapeText') { if (e.args.text === '') { if (e.reason !== 'checkUIElementAvailability') { showToast('A shape text cannot be empty.'); } e.allowed = false; } } else if (e.operation === 'beforeChangeConnectorText') { e.allowed = false; } }, []); return ( <Diagram id="diagram" ref={diagramRef} onRequestEditOperation={onRequestEditOperation} onRequestLayoutUpdate={onRequestLayoutUpdate} > <CustomShape category="items" type="root" baseType="octagon" defaultText="Development" /> <CustomShape category="items" type="team" baseType="ellipse" title="Team" defaultText="Team Name" /> <CustomShape category="items" type="employee" baseType="rectangle" title="Employee" defaultText="Employee Name" /> <Nodes dataSource={orgItemsDataSource} keyExpr="ID" textExpr="Name" typeExpr="Type" parentKeyExpr="ParentID" styleExpr={itemStyleExpr} > <AutoLayout type="tree" /> </Nodes> <ContextToolbox shapeIconsPerRow={2} width={100} shapes={shapes as any}> </ContextToolbox> <Toolbox shapeIconsPerRow={2}> <Group title="Items" shapes={shapes as any} /> </Toolbox> <PropertiesPanel visibility="disabled"> </PropertiesPanel> </Diagram> ); }