Fix bug

app.py

@@ -7,14 +7,14 @@ def enable_second_task(secret):
     if secret == os.environ["SECRET_KEY"]:
         return [
             gr.Textbox.update(visible=False),
-            gr.HTML(visible=False),
+            gr.HTML.update(visible=False),
             gr.Button.update(visible=False),
             gr.Textbox.update(visible=True),
             gr.Textbox.update(visible=True),
             gr.Button.update(visible=True)                                                
         ]
     return [
-        gr.Textbox.update(visible=True),
+        gr.Textbox.update(value="", visible=True),
         gr.HTML.update(visible=True),
         gr.Button.update(visible=True),
         gr.Textbox.update(visible=False),
@@ -29,7 +29,8 @@ demo = gr.Blocks()
 with demo:
     # Authentication
     secret_textbox = gr.Textbox(
-        placeholder="Enter secret key", label="Secret", show_label=True
+        placeholder="Enter secret key", label="Secret", show_label=True,
+        max_lines=1
     )    
     error_message = gr.HTML(
         "<span style=\"color: red;\">Wrong secret key. Please retry</span>",
@@ -46,6 +47,13 @@ with demo:
     )    
     greet_button = gr.Button("Greet", visible=False)    
     
+    # Event handling
+    secret_textbox.submit(
+        enable_second_task,
+        secret_textbox,
+        [secret_textbox, error_message, secret_button,
+         name_textbox, greet_textbox, greet_button]        
+    )
     secret_button.click(
         enable_second_task,
         secret_textbox,