private void TextTopic_QuerySubmitted(AutoSuggestBox sender, AutoSuggestBoxQuerySubmittedEventArgs args)
{
txtContent.Text += args.QueryText;
TopicFlyout.Hide();
}
private void listTopic_ItemClick(object sender, ItemClickEventArgs e)
{
txtContent.Text += (e.ClickedItem as RcmdTopicModel).display;
TopicFlyout.Hide();
}