Update index.tsx

src/views/prepare-lessons/components/lesson-main/courseware-presets/index.tsx

@@ -421,11 +421,15 @@ export default defineComponent({
           style={{ width: `calc(${forms.leftWidth} - ${forms.rightWidth})` }}>
           <NTabs
             ref={subjectRef}
-            defaultValue="subject"
+            defaultValue=""
             paneClass={styles.paneTitle}
             justifyContent="start"
             paneWrapperClass={styles.paneWrapperContainer}
-            value={prepareStore.getSubjectId?.toString()}
+            value={
+              prepareStore.getSubjectId
+                ? prepareStore.getSubjectId?.toString()
+                : ''
+            }
             onUpdate:value={val => {
               prepareStore.setSubjectId(val);
               // 保存