private void BuildAppBar()
{
_appBarButtons = new List<ApplicationBarIconButton>();
_appBarButtons.Add(new ApplicationBarIconButton());
_appBarButtons[0].IconUri = new Uri("\\Assets\\Icons\\new.png", UriKind.Relative);
_appBarButtons[0].Text = "new";
_appBarButtons[0].IsEnabled = true;
_appBarButtons[0].Click += New_Click;
_appBarButtons.Add(new ApplicationBarIconButton());
_appBarButtons[1].IconUri = new Uri("\\Assets\\Icons\\reply.png", UriKind.Relative);
_appBarButtons[1].Text = "reply";
_appBarButtons[1].IsEnabled = false;
_appBarButtons[1].Click += Reply_Click;
_appBarButtons.Add(new ApplicationBarIconButton());
_appBarButtons[2].IconUri = new Uri("\\Assets\\Icons\\refresh.png", UriKind.Relative);
_appBarButtons[2].Text = "refresh";
_appBarButtons[2].IsEnabled = true;
_appBarButtons[2].Click += Refresh_Click;
ApplicationBar.Buttons.Clear();
foreach (var button in _appBarButtons)
ApplicationBar.Buttons.Add(button as IApplicationBarIconButton);
}