labelStyle property Null safety
The style to be applied to the chip's label.
The default label style is TextTheme.bodyLarge from the overall theme's ThemeData.textTheme. This only has an effect on widgets that respect the DefaultTextStyle, such as Text.
If TextStyle.color is a MaterialStateProperty<Color>, MaterialStateProperty.resolve is used for the following MaterialStates:
@override final TextStyle? labelStyle;