import { Designer } from '@alilc/lowcode-designer'; import { designerSymbol } from './symbols'; import DropLocation from './drop-location'; export default class Canvas { private readonly [designerSymbol]: Designer; constructor(designer: Designer) { this[designerSymbol] = designer; } static create(designer: Designer) { if (!designer) return null; return new Canvas(designer); } get dropLocation() { return DropLocation.create(this[designerSymbol].dropLocation || null); } }