appBar property
*** general properties start *** CupertinoPageScaffold.navigationBar or Scaffold.appBar If this properties is null, then navBar is use.
If this parameter is null, then navBar will be used
Implementation
/// [CupertinoPageScaffold.navigationBar]
/// or
/// [Scaffold.appBar]
/// If this properties is null, then [navBar] is use.
///
/// If this parameter is null, then [navBar] will be used
final BaseAppBar? appBar;