fix 显示预览生成重置

@@ -517,6 +517,7 @@
   >
     <div class="preview-container">
       <vue-flow-editor-form
+        v-if="rawFlowData"
         ref="editor1"
         :height="state.window_height"
         :data="rawFlowData"
@@ -800,6 +801,7 @@ export default {
 
     const getFlowData = async (flow_id: any) => {
       flowData.value = null;
+      rawFlowData.value = null;
       state.reloadLoading = true; // 打开loading
       const { code, data } = await flowNodesAPI({ flow_id });
       if (code) {