TabBarView PageView에서 위젯 리빌드 방지

 

 

 

PageView등에서 children 위젯을 여러개 가질경우, 네비게이션바에서 그페이지가 아닌 

다른 페이지를 들어가도, 전체 위젯이 계속 빌드됨..

불필요한 rebuild를 막기위한 방법..

 

stackoverflow.com/questions/57704265/how-to-prevent-rebuild-statelesswidget-children-of-pageview

How to prevent rebuild StatelessWidget children of PageView

 

 

const keyword

• Make your widgets accept to be const:@override Widget build(BuildContext context) { debugPrint("FirstPage.build"); return Container( child: Center( child: Text("First Page"), ), ); }}
• class FirstPage extends StatelessWidget { const FirstPage({Key key}) : super(key: key);
• and call it with const keyword:return Scaffold( appBar: AppBar( title: Text(widget.title), ), body: PageView( children: <Widget>[ const firstPage(), const secondPage(), ], ), );

2. AutomaticKeepAliveClientMixin

• Convert your StatelessWidget to StatefullWidget.

class FirstPage extends StatefulWidget { FirstPage({Key key}) : super(key: key); @override _FirstPageState createState() => _FirstPageState(); } class _FirstPageState extends State<FirstPage> { @override Widget build(BuildContext context) { debugPrint("FirstPage.build"); return Container( child: Center( child: Text("First Page"), ), ); } }

• Extends AutomaticKeepAliveClientMixin on StatefullWidget created State.

class _FirstPageState extends State<FirstPage> with AutomaticKeepAliveClientMixin {

• Call super on the build method.

@override Widget build(BuildContext context) { super.build(context); debugPrint("FirstPage.build"); return Container( child: Center( child: Text("First Page"), ), ); }

• Override wantKeepAlive getter with true returned value.

@override bool get wantKeepAlive => true;