fix

@@ -489,14 +489,14 @@
         :onRef="onRef"
         :multipleSelect="showMultipleSelect"
         :loading="state.editorLoading"
+        @click-canvas="onClickCanvasPreview"
         @click-node="onClickNodePreview"
         :controlConfig="state.controlConfig"
         :toolbarButtonHandler="toolbarButtonHandler"
       ></vue-flow-editor-form>
     </div>
     <div class="preview-detail-container">
-      {{ state.detailModel }}
-      <iframe src="https://oa-dev.onwall.cn/f/custom_form/front/index.html#/?code=fboupg&model=preview" width="100%" height="100%" style="border: 0;"></iframe>
+      <iframe :src="state.preview_form_url" width="100%" height="100%" style="border: 0;"></iframe>
     </div>
     <template #footer>
       <span class="dialog-footer">
@@ -674,7 +674,8 @@ export default {
       node_attr: {},
       node_tree: {},
       show_preview: false,
-      window_height: '500px'
+      window_height: '500px',
+      preview_form_url: '',
     });
 
     const setNodeTree = (id: string, data: object) => {
@@ -2268,6 +2269,20 @@ export default {
       model.data = model.data ? model.data : {};
 
       state.detailModel = model;
+      console.warn(model);
+      if (model.id !== 'start-node') {
+        state.preview_form_url = 'https://oa-dev.onwall.cn/f/custom_form/front/index.html#/?code=fboupg&model=preview'
+      } else {
+        state.preview_form_url = null;
+      }
+    }
+
+    /**
+     * 单击画布预览回调
+     * @param {Event} e - The event object representing the click event.
+     */
+    const onClickCanvasPreview = () => {
+      state.preview_form_url = null;
     }
 
     return {
@@ -2326,8 +2341,10 @@ export default {
       saveData,
       startFlow,
       toolbarButtonHandler,
+
       openPreview,
       onClickNodePreview,
+      onClickCanvasPreview,
 
       onRef: (e: any) => (editor = e),
       staticPath,