warning method

Implementation

ButtonStyle warning() {
  return copyWith(
    backgroundColor: WidgetStateProperty.all(
      Color(0xFFffc107),
    ), // Bootstrap warning yellow
    foregroundColor: WidgetStateProperty.all(
      Color(0xFF212529),
    ), // Bootstrap dark text
    shape: WidgetStateProperty.all(
      RoundedRectangleBorder(borderRadius: BorderRadius.circular(4.0)),
    ),
  );
}