/// <summary>
/// Shows the current controls screen as well as scroll arrows.
/// </summary>
private void UpdateTopicList()
{
int index = topicEntryList.GetEntry().index;
currentTopicText.text = topics[index].topic;
upArrow.SetActive(topicEntryList.CanScrollUp());
downArrow.SetActive(topicEntryList.CanScrollDown());
for (int i = 0; i < topics.Count; i++)
{
topics[i].screen.SetActive(i == index);
}
}