The question about zeroOffset in swerve

Our team is trying to use swerve. l use the Official WPILIB’s swerve example as my example . In the WPI’s example , there seems to be no zerooffset. But when l tune my swerve in the lab, l found that it is still necessary to set an zeroOffset. Or has WPI’s official lib contains this function, so how to use it ? Or, how can l reach this function , with WPI’s swerve methods?

Any answer is appreciated.