修复首次打开画布无法加载节点问题

src/components/Canvas/FlowCanvas/manager/NodeManager.ts

@@ -54,6 +54,7 @@ export class NodeManager {
 			return current.data.createIndexPosition > max.data.createIndexPosition ? current : max
 		}, superiorGenerateNodes[0])
 		const snode = superiorID ? this.stateManager.flowManager.getNodeById(superiorID) : this.stateManager.flowManager.getLastNode();
+		console.log(snode)
 		const id = options.id || createId()
 		const positionX = options.positionX || 0
 		const positionY = options.positionY || 0
@@ -65,10 +66,14 @@ export class NodeManager {
 				{
 					x: endGenerateNode.position.x + positionX,
 					y: endGenerateNode.position.y + positionY + this.ranksep + 200
-				} :
+				} : snode ?
 				{
 					x: snode.position.x + snode.dimensions.width + this.nodesep + positionX,
 					y: snode.position.y + positionY
+				} :
+				{
+					x: positionX,
+					y: positionY
 				}
 			)
 		const data = options?.data || {}