Scaffold, AppBar, Column, ... 但只要重建已更改的小部件就足够了。让我们看下一个代码示例: import 'package:flutter/material.dart'; classHome2 extends StatefulWidget { constHome2({Key? key}) : super(key: key); @override State<Home2> createState() => _State(); } class_State extends Stat...
appBar: AppBar(title: Text("Flutter Set Example")), body: Center( child: Button( onPressed: () { // 设置Button文本 widget.text = "Flutter is awesome!"; // 设置Button颜色 widget.color = Colors.blue; }, child: Text( "Press me!", style: TextStyle(fontSize: 24), ), ), ), )...
这里是我的代码示例String check="go to next page";String check2="state1";Widget page3(){ return return FlatButton( child:Text(check2) shape: RoundedRectangleBorder( borderRadius: BorderRadius.circular(18.0), side: BorderSide(color: Colors.blue[100])), color: Colors.white, onPressed: (){ ...
import'package:flutter/material.dart';classHome2extendsStatefulWidget{constHome2({Key?key}):super(key:key);@overrideState<Home2>createState()=>_State();}class_StateextendsState<Home2>{@overrideWidgetbuild(BuildContextcontext){print("builtmethodHome2");returnScaffold(appBar:AppBar(title...
Dart/Flutter 页面在 SetState 后不重新加载 我有一个关注/取消关注按钮,它根据公共(public)字符串的值更改 UI。问题是在 String 的值发生变化并且调用 setState 之后 UI 保持不变。如果我重新加载页面,那么它可能会改变。这是我的代码... var friends;...
(); break; case 1: setState(() {}); return _buildLanguage(); break; case 2: setState(() {}); return _buildContact(); break; case 3: setState(() {}); return _buildThemeColor(); break; } } @override Widget build(BuildContext context) { return new Scaffold( appBar: AppBar(...
import 'package:flutter/material.dart'; class FilterPage extends StatefulWidget { final Color color; const FilterPage({Key? key, required this.color}) : super(key: key); @override _FilterPageState createState() => _FilterPageState(); ...
我正在尝试构建一个 Flutter 应用程序,但我一直在尝试动态更新列表中项目的数量。我正在从本地读取 json 文件,然后将其保存到 MyAppState 中的列表中。然后该列表将在 gridview 中显示给用户。列表中的每个项目都有一个加号和减号按钮,我可以使用 onPressed() 从用户的项目“集合”中添加/删除项目。我目前面临的...
), ), bottomNavigationBar: BottomAppBar( // color: Colors.white, elevation: 0.0, hasNotch: false, child: BottomNavigationBar( currentIndex: currentTab, onTap: (index) { setState(() { tapCount++; currentTab = index; }); }, type: BottomNav...
buttonColor = _isButtonPressed ? Colors.red : Colors.blue; }); } @override Widget build(BuildContext context) { return MaterialApp( home: Scaffold( appBar: AppBar( title: Text('Flutter Example'), ), body: Center( child: RaisedButton( onPressed: _handleButtonPress, color: _buttonColor, ...