home: HomePage(), )); } class HomePage extends StatelessWidget { @override Widget build(BuildContext context) { return Scaffold( appBar: AppBar( title: Text('Home Page'), ), body: Center( child: ElevatedButton( child: Text('Go to New Page'), onPressed: () { ...
IconButton( // 1 icon: Icon(_isFavorited ? Icons.favorite : Icons.favorite_border), iconSize: 30, // 2 color: Colors.red[400], onPressed: () { // 3 setState(() { _isFavorited = !_isFavorited; }); }, ) Here’s how the new state works: First, it checks if the user ...
CupertinoButton( onPressed: () {// This closure is called when your button is tapped.}, const Text('Do something'), ), open_in_newcontent_copy Fluttergives you access to a variety of buttons with predefined styles. TheCupertinoButtonclass comes from the Cupertino library. Widgets in the Cupe...
// to the screen. RaisedButton( child: Text("Navigate to a named that accepts arguments"), onPressed: () { // When the user taps the button, navigate to a named route // and provide the arguments as an optional parameter. Navigator.pushNamed( context, PassArgumentsScreen.routeName, argum...
we execute flutter’s inbuilt function runApp from flutter’s widget library which inflates the given widget/class and attaches it to the screen, and we pass the class’s object as MyApp(), without a new keyword like a function which you may familiar from other languages, those parentheses...
onPressed: () { Navigator.push( context, MaterialPageRoute(builder: (context) => Settings()), ); }, ) ], ), body: ... ); } }Code language:Dart(dart) With this code in place, when we reload our app we should see the localized value of our tooltip in theWidget Inspector. ...
onPressed: () async { final now = DateTime.now(); final result = await showDatePicker( context: context, initialDate: now, firstDate: now.subtract( const Duration( days: 90, ), ), lastDate: now); if (result != null) { setState(() { ...
onPressed: () { _controller.text = "newText"; //每次修改内容的时候需要再手动修改selection _controller.selection = TextSelection.fromPosition( TextPosition(offset: _controller.text.length)); }, child: Text("click me"), ), TextField(
If the Widget supports event detection, pass a function to it and handle it in the function. For example, the RaisedButton has anonPressedparameter: @override Widget build(BuildContext context) { return new RaisedButton( onPressed: () { ...
watch(counterStateProvider); return ElevatedButton( // 2. use the value child: Text('Value: $counter'), // 3. change the state inside a button callback onPressed: () => ref.read(counterStateProvider.notifier).state++, ); } }