if result_gallery is not None:

gradio_demo.py

@@ -446,8 +446,9 @@ def load_and_reset(param_setting):
 
 def log_information(result_gallery):
     print('log_information')
-    for i, result in enumerate(result_gallery):
-        print(result[0][0])
+    if result_gallery is not None:
+        for i, result in enumerate(result_gallery):
+            print(result[0][0])
 
 def on_select_result(result_gallery, evt: gr.SelectData):
     print('on_select_result')