[Flutter] AppBar title 가운데 정렬

@override
Widget build(BuildContext context) {
  return AppBar(
    title: title != null
        ? Text(
            title!,
            style: CGTextStyle.subtitle1.copyWith(color: CGColor.text_1st),
          )
        : null,
    centerTitle: true, // 타이틀을 가운데로 정렬합니다.
    leading: leading,
    actions: actions,
    backgroundColor: Colors.transparent,
    bottomOpacity: 0.0,
    elevation: 0.0,
    scrolledUnderElevation: 0,
  );
}