你知道吗，Flutter内置了10多种show

showDialog(
    context: context,builder: (context) {
      return AlertDialog(
        ...
      );
    }
);

Navigator.of(context,rootNavigator: true).pop(result)

Navigator.pop(context,result)

showCupertinoDialog(
    context: context,builder: (context) {
      return CupertinoAlertDialog(
       ...
      );
    });

showGeneralDialog(
    context: context,barrierDismissible:true,barrierLabel: '',transitionDuration: Duration(milliseconds: 200),pageBuilder: (BuildContext context,Animation<double> animation,Animation<double> secondaryAnimation) {
      return Center(
        child: Container(
          height: 300,width: 250,color: Colors.lightGreenAccent,),);
    });

showGeneralDialog(
    context: context,barrierColor: Colors.black.withOpacity(.5),...
  )

showGeneralDialog(
    transitionBuilder: (BuildContext context,Animation<double> secondaryAnimation,Widget child) {
      return ScaleTransition(scale: animation,child: child);
    },...
  )

showAboutDialog(
  context: context,applicationIcon: Image.asset(
    'images/bird.png',height: 100,width: 100,applicationName: '应用程序',applicationVersion: '1.0.0',applicationLegalese: 'copyright 老孟，一枚有态度的程序员',children: <Widget>[
    Container(
      height: 30,color: Colors.red,Container(
      height: 30,color: Colors.blue,color: Colors.green,)
  ],);

• applicationIcon：应用程序的图标。
• applicationName：应用程序名称。
• applicationVersion：应用程序版本。
• applicationLegalese：著作权（copyright）的提示。
• children：位置如上图的红蓝绿色的位置。

1. 在pubspec.yaml中配置支持国际化：

dependencies:
  flutter:
    sdk: flutter
  flutter_localizations:
    sdk: flutter

2. 在MaterialApp中配置当前区域：

MaterialApp(
      title: 'Flutter Demo',localizationsDelegates: [
        GlobalMaterialLocalizations.delegate,GlobalWidgetsLocalizations.delegate,],supportedLocales: [
        const Locale('zh','CH'),const Locale('en','US'),locale: Locale('zh'),...
  )

showLicensePage(
  context: context,);

showBottomSheet(
    context: context,builder: (context) {
      return Container(height: 200,color: Colors.lightBlue);
    });

showBottomSheet(
    context: context,backgroundColor: Colors.lightGreenAccent,elevation:20,shape: CircleBorder(),builder: (context) {
      return Container(height: 200);
    });

showModalBottomSheet(
        context: context,builder: (BuildContext context) {
          return BottomSheet(...);
        });

showModalBottomSheet(
    context: context,backgroundColor: Colors.lightBlue,elevation: 10,shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(30)),...
  )

showModalBottomSheet(
    context: context,isScrollControlled: true,builder: (BuildContext context) {
      return ListView.builder(
        itemBuilder: (context,index) {
          return ListTile(
            title: Text('老孟$index'),);
        },itemExtent: 50,itemCount: 50,);
    });

showCupertinoModalPopup(
    context: context,builder: (BuildContext context) {
      return CupertinoActionSheet(
        title: Text('提示'),message: Text('是否要删除当前项？'),actions: <Widget>[
          CupertinoActionSheetAction(
            child: Text('删除'),onPressed: () {},isDefaultAction: true,CupertinoActionSheetAction(
            child: Text('暂时不删'),isDestructiveAction: true,);
    }
);

showCupertinoModalPopup(
    context: context,filter: ImageFilter.blur(sigmaX: 5.0,sigmaY: 5.0),...
  )

showMenu(
    context: context,position: RelativeRect.fill,items: <PopupMenuEntry>[
      PopupMenuItem(child: Text('语文')),PopupMenuDivider(),CheckedPopupMenuItem(
        child: Text('数学'),checked: true,PopupMenuItem(child: Text('英语')),]);

final RenderBox button = context.findRenderObject();
final RenderBox overlay = Overlay.of(context).context.findRenderObject();
final RelativeRect position = RelativeRect.fromRect(
  Rect.fromPoints(
    button.localToGlobal(Offset(0,0),ancestor: overlay),button.localToGlobal(button.size.bottomRight(Offset.zero),Offset.zero & overlay.size,);

showSearch(context: context,delegate: CustomSearchDelegate());

class CustomSearchDelegate extends SearchDelegate<String>{
  @override
  List<Widget> buildActions(BuildContext context) {
    return null;
  }

  @override
  Widget buildLeading(BuildContext context) {
    return null;
  }

  @override
  Widget buildResults(BuildContext context) {
    return null;
  }

  @override
  Widget buildSuggestions(BuildContext context) {
    return null;
  }

}

@override
Widget buildLeading(BuildContext context) {
  return IconButton(
    icon: Icon(Icons.arrow_back,onPressed: (){
      close(context,'');
    },);
}

@override
Widget buildSuggestions(BuildContext context) {
  return ListView.separated(
    itemBuilder: (context,index) {
      return ListTile(
        title: Text('老孟 $index'),onTap: () {
          query = '老孟 $index';
        },);
    },separatorBuilder: (context,index) {
      return Divider();
    },itemCount: Random().nextInt(5),);
}

@override
List<Widget> buildActions(BuildContext context) {
  return [
    IconButton(
      icon: Icon(
        Icons.clear,onPressed: () {
        query = '';
      },)
  ];
}

@override
Widget buildResults(BuildContext context) {
  return ListView.separated(
    itemBuilder: (context,index) {
      return Container(
        height: 60,alignment: Alignment.center,child: Text(
          '$index',style: TextStyle(fontSize: 20),itemCount: 10,);
}