public void OpenTweetFlyOutAction() { if (IsOpenSetting) { return; } var tweets = Messanger.SelectedTweets; if ((tweets?.Count() ?? 0) == 0) { var afterIsOpen = !IsOpenTweetFlyOut.Value && !IsOpenSetting; IsOpenTweetFlyOut.Value = afterIsOpen; if (!afterIsOpen) { SendErrorVisibility.Value = Visibility.Collapsed; } return; } App.Current.Dispatcher.Invoke(() => Tweet.AddReply(tweets)); IsOpenTweetFlyOut.Value = true; }