How to determine whether the player accepts the operation code

I want to use the operation code: SMSG_ QUEST_ CONFIRM_ ACCESS, adding a pop-up function in the game, the challenge now is the pop-up confirmation window. How can I determine if the player has clicked to accept or cancel?

  std::string text = "Your confirmation message";
  uint32 id = 123
  WorldPacket data(SMSG_QUEST_CONFIRM_ACCEPT, (4 + text.size() + 8));
  data << uint32(id);
  data << text;
  data << (GetPlayer()->GetGUID());