要创建对话框，可以使用Overlay 或Dialog类。如果要像在给定框架中那样添加动画，则可以像以下示例中那样使用AnimationController。该
CurvedAnimation类是用于创建动画的弹跳效果。
更新：通常，最好使用
showDialog函数显示对话框，因为关闭和手势由Flutter处理。我已经更新了该示例，该示例现在与之一起运行，showDialog您可以通过点击背景来关闭对话框。
弹跳对话框动画
您可以将以下代码复制并粘贴到新项目中并进行调整。它本身是可运行的。
import 'package:flutter/material.dart';void main() => runApp(new MyApp());class MyApp extends StatelessWidget { @override Widget build(BuildContext context) { return MaterialApp(title: 'Flutter Demo', theme: ThemeData(), home: Page()); }}class Page extends StatelessWidget { @override Widget build(BuildContext context) { return Scaffold( body: Center( child: RaisedButton.icon( onPressed: () { showDialog( context: context, builder: (_) => FunkyOverlay(), ); }, icon: Icon(Icons.message), label: Text("PopUp!")), ), ); }}class FunkyOverlay extends StatefulWidget { @override State<StatefulWidget> createState() => FunkyOverlayState();}class FunkyOverlayState extends State<FunkyOverlay> with SingleTickerProviderStateMixin { AnimationController controller; Animation<double> scaleAnimation; @override void initState() { super.initState(); controller = AnimationController(vsync: this, duration: Duration(milliseconds: 450)); scaleAnimation = CurvedAnimation(parent: controller, curve: Curves.elasticInOut); controller.addListener(() { setState(() {}); }); controller.forward(); } @override Widget build(BuildContext context) { return Center( child: Material( color: Colors.transparent, child: ScaleTransition( scale: scaleAnimation, child: Container( decoration: ShapeDecoration( color: Colors.white, shape: RoundedRectangleBorder( borderRadius: BorderRadius.circular(15.0))), child: Padding( padding: const EdgeInsets.all(50.0), child: Text("Well hello there!"), ), ), ), ), ); }}
