Update app.py

app.py

@@ -90,9 +90,10 @@ def play_tic_tac_toe(evt: gr.SelectData, board, game_over):
     print(f"Event = {evt}")
     # print(f"Index = {evt.index}")
     
-    if evt is None:
-        return draw_board(board), "Invalid action! Please click on the board.", False
-    
+    # 確認 evt 是否有效
+    if not evt or not evt.index:
+        return draw_board(board), "Invalid move! Please select a valid square.", False
+
     if game_over:
         return draw_board(board), "Game already finished! Please reset to play again.", True