textStyle property Null safety
final
The style to use for the message of the tooltip.
If null, the message's TextStyle will be determined based on ThemeData. If ThemeData.brightness is set to Brightness.dark, TextTheme.bodyText2 of ThemeData.textTheme will be used with Colors.white. Otherwise, if ThemeData.brightness is set to Brightness.light, TextTheme.bodyText2 of ThemeData.textTheme will be used with Colors.black.
Implementation
final TextStyle? textStyle;