Update app.py

app.py

@@ -451,6 +451,9 @@ if __name__ == '__main__':
      
         async def upload_handler(files):
 
+            if files is None:
+                return [], 0, ""
+
             if files.lower().endswith(".pdf"):
                 asyncio.create_task(send_pdf_async_aiohttp(files, server_ip=openai_api_base, Authorization=Authorization))
             
@@ -461,6 +464,10 @@ if __name__ == '__main__':
             upload_handler,
             inputs=file,
             outputs=[img_list_state, idx_state, viewer],
+        ).then(
+            lambda: gr.Slider.update(value=1),   # 无输入，直接把 zoom 设为 1
+            None,                                # inputs=None
+            zoom                                 # outputs=[zoom]
         )
     
         def show_prev(b64s, idx, scale):