void JoinOrLeave()
{
if ((tv_Sessions.SelectedNode != null) && (tv_Sessions.SelectedNode.Tag != null))
{
var session = (ISession)tv_Sessions.SelectedNode.Tag;
if (session == null)
{
return;
}
if (joined.Contains(session))
{
presenter.Leave(session);
btn_Join.Text = Constants.JOIN;
tv_Sessions.SelectedNode.BackColor = listened.Contains(session) ? Constants.LISTENING_COLOR : tv_Sessions.BackColor;
}
else
{
presenter.Join(session);
btn_Join.Text = Constants.LEAVE;
tv_Sessions.SelectedNode.BackColor = Constants.JOINED_COLOR;
}
}
}