场景1: 在Push或Pop时不rebuild(默认) class_XCTestViewStateextendsXCState{@overrideWidgetshouldBuild(BuildContextcontext){returnCenter(child:Text("_XCTestView, if you use `shouldBuild`, it can avoid rebuilding when pushing or popping"));}voidaFunc(){reload()}} 场景2: 也可以重写参照物方法,决定...
@protectedvoidsetState(VoidCallback fn){//断言fn不为空assert(fn!=null);assert((){//当前State的状态,不能等于_StateLifecycle.defunct,//该状态时,dispose函数已经调用if(_debugLifecycleState==_StateLifecycle.defunct){throwFlutterError.fromParts(<DiagnosticsNode>[ErrorSummary('setState() called after di...
/// Override this method to build widgets that depend on the state of the /// listenable (e.g., the current value of the animation). @protected Widget build(BuildContext context); /// Subclasses typically do not override this method. @override _AnimatedState createState() => _AnimatedSta...
Thankfully no again and again rebuilding of the whole widget.No matter the widget which is wrapped under the Stateful Builder is in Stateless or stateful Widget. Now question arising is we know Stateless Widget it can’t rebuild until it gets a new instance. ( SetState is not working)...
[builder] callback's return value contains a subtree that does not/// depend on the animation, it's more efficient to build that subtree once/// instead of rebuilding it on every animation tick./// If the pre-built subtree is passed as the [child] parameter, the/// [AnimatedBuilder...
When building widgets, or using flutter widgets. This helps flutter only rebuild widgets that should be updated. The widgets do not change when setState is called. It will prevent widgets from rebuilding. You can save CPU cycles and use them with const constructors. ...
Otherwise, the framework might not visit this widget during this build phase. The widget on which setState() or markNeedsBuild() was called was: MenuAnchor The widget which was currently being built when the offending call was made was: MenuAnchor The relevant error-causing widget was: Menu...
@override Widget build(BuildContext context) { print('MyWidgetState - build'); return Row( children: [ Expanded( child: Column( mainAxisAlignment: MainAxisAlignment.center, crossAxisAlignment: CrossAxisAlignment.center, children: [ StatefulBuilder(builder: (context, setState) { print('StatefulWidget...
Can I change the language of my Flutter app at runtime? Yes, you can change the language of your Flutter app at runtime by updating the current locale using the “Locale” class, and then rebuilding the app’s UI using the “setState” method.Happy learning Flutter!Related...
When I change SystemUiMode when rebuilding the app, the page's widgets are being moved and status bar area becomes completely black. This behavior occurs on my physical Android device which is Redmi Note 10 with operating system MIUI 12...