Is there an official way or trick to open the Windows Phone ApplicationBar using C# from the code-behind? I'd like to show my users additional options hidden in the menu.
To be clear, I don't need to create the menu in code-behind (but can, if that helps in any way).
There are no way to open application bar programmatically. But you can create application bar in C#. Here is the sample.
ApplicationBar = new ApplicationBar();
ApplicationBar.Mode = ApplicationBarMode.Default;
ApplicationBar.Opacity = 1.0;
ApplicationBar.IsVisible = true;
ApplicationBar.IsMenuEnabled = true;
ApplicationBarIconButton button1 = new ApplicationBarIconButton();
button1.IconUri = new Uri("/Images/YourImage.png", UriKind.Relative);
button1.Text = "button 1";
ApplicationBar.Buttons.Add(button1);
ApplicationBarMenuItem menuItem1 = new ApplicationBarMenuItem();
menuItem1.Text = "menu item 1";
ApplicationBar.MenuItems.Add(menuItem1);