We have found that when you follow the code here on Screensteps: http://wpilib.screenstepslive.com/s/3120/m/7932/l/81114-setting-robot-preferences-from-smartdashboard you get a null pointer exception. When you initialize the Preference object, you receive a not visible error, we’re assuming this is because the constructor for preferences is private. How do we get this to work?
You need a line like:
Preferences* prefs = Preferences::GetInstance();
Preferences prefs = Preferences.getInstance();
depending on the language.