I am having issues with running the robot in Test Mode and displaying widgets in SmartDashboard. If I enable the robot all widgets on the SmartDashboard disappears. If I disable the robot all the widgets reappear. This is only an issue with Test Mode as no such error occurred running the robot in Teleop.
Using Test mode enables LiveWindow mode on the SmartDashboard. It removes the SmartDashboard widgets and shows the LiveWindow widgets. RobotBuilder will automatically add the required LiveWindow calls, but if you aren’t using RobotBuilder, you’ll need to add the LiveWindows calls yourself.
See http://wpilib.screenstepslive.com/s/3120/m/8564/l/87776-using-test-mode
It looks like with today’s java update, you no longer need to add the LiveWindow add methods to your code, although you can if you want to control how things are grouped. See http://wpilib.screenstepslive.com/s/3120/m/8559/l/92653-2013-software-notes and http://wpilib.screenstepslive.com/s/3120/m/7932/l/92264-enabling-test-mode-livewindow