Fix PDF documents

app.py

@@ -100,6 +100,7 @@ def process_path(path):
                 gr.update(visible=True),
                 gr.update(visible=False, value=None),
                 gr.update(visible=False, value=None),
+                None,
             )
         except Exception as e:
             traceback.print_exc()
@@ -111,6 +112,7 @@ def process_path(path):
         gr.update(visible=False, value=None),
         gr.update(visible=False, value=None),
         gr.update(visible=True, value=error) if error is not None else None,
+        None,
     )