flutter 頁面緩存

flutter頁面緩存方法：

混入AutomaticKeepAliveClientMixin部件設置頁面緩存：

//在動態部件內
class Page1 extends StatefulWidget {
  @override
  _Page1State createState() => _Page1State();
}
//混入AutomaticKeepAliveClientMixin 設置緩存
class _Page1State extends State<MyHomePage> with AutomaticKeepAliveClientMixin {
  //重寫keepAlive爲ture  開啓緩存功能。
  @override
  bool get wantKeepAlive => true;
  
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('緩存頁面')),
      boby: IndexedStack(
		 //用來顯示第index個child，
		 index: childIndex,
		 children: <Widget>['這裏面存放你需要緩存的頁面內容'],
	  )
    )
  }