trackColor property

MaterialStateProperty<Color?>? trackColor
final

The color of this Switch's track.

Resolved in the following states:

This example resolves the trackColor based on the current MaterialState of the Switch, providing a different Color when it is MaterialState.disabled.
link 
Switch(
  value: true,
  onChanged: (bool value) { },
  thumbColor: MaterialStateProperty.resolveWith<Color>((Set<MaterialState> states) {
    if (states.contains(MaterialState.disabled)) {
      return Colors.orange.withOpacity(.48);
    }
    return Colors.orange;
  }),
)

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 following colors are used:

State Light theme Dark theme
Default Color(0x52000000) Colors.white30
Selected activeColor with alpha 0x80 activeColor with alpha 0x80
Disabled Colors.black12 Colors.white10

Implementation

final MaterialStateProperty<Color?>? trackColor;