Only create and add GaugePanel when necessary The GaugePanel isn't created always and only show if WINFO and a river is selected now. It is only created on demand. Therefore all access to the GaugePanel is abstraced via methods that check if the GaugePanel is null before accessing it's methods.

SYMBOLSET
SYMBOL
  NAME 'point'
  TYPE ELLIPSE
  POINTS
    1 1
  END
  FILLED TRUE
END
SYMBOL
  NAME "square"
  TYPE VECTOR
  POINTS
    0 0
    0 1
    1 1
    1 0
    0 0
  END
  FILLED TRUE
END
END