trackColor property
final
The color of this switch's track.
Resolved in the following states:
If null, then the value of activeTrackColor is used in the selected state and inactiveTrackColor in the default state. If that is also null, then the value of SwitchThemeData.trackColor is used. If that is also null, then the default value is used.
Implementation
final MaterialStateProperty<Color?>? trackColor;