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| 1 | +import 'package:exercise/home.dart'; |
1 | 2 | import 'package:flutter/material.dart';
|
2 | 3 |
|
3 | 4 | void main() {
|
4 |
| - runApp(MyApp()); |
| 5 | + runApp(App()); |
5 | 6 | }
|
6 | 7 |
|
7 |
| -class MyApp extends StatelessWidget { |
8 |
| - // This widget is the root of your application. |
| 8 | +class App extends StatelessWidget { |
9 | 9 | @override
|
10 | 10 | Widget build(BuildContext context) {
|
11 | 11 | return MaterialApp(
|
12 |
| - title: 'Flutter Demo', |
13 |
| - theme: ThemeData( |
14 |
| - // This is the theme of your application. |
15 |
| - // |
16 |
| - // Try running your application with "flutter run". You'll see the |
17 |
| - // application has a blue toolbar. Then, without quitting the app, try |
18 |
| - // changing the primarySwatch below to Colors.green and then invoke |
19 |
| - // "hot reload" (press "r" in the console where you ran "flutter run", |
20 |
| - // or simply save your changes to "hot reload" in a Flutter IDE). |
21 |
| - // Notice that the counter didn't reset back to zero; the application |
22 |
| - // is not restarted. |
23 |
| - primarySwatch: Colors.blue, |
24 |
| - // This makes the visual density adapt to the platform that you run |
25 |
| - // the app on. For desktop platforms, the controls will be smaller and |
26 |
| - // closer together (more dense) than on mobile platforms. |
27 |
| - visualDensity: VisualDensity.adaptivePlatformDensity, |
28 |
| - ), |
29 |
| - home: MyHomePage(title: 'Flutter Demo Home Page'), |
30 |
| - ); |
31 |
| - } |
32 |
| -} |
33 |
| - |
34 |
| -class MyHomePage extends StatefulWidget { |
35 |
| - MyHomePage({Key key, this.title}) : super(key: key); |
36 |
| - |
37 |
| - // This widget is the home page of your application. It is stateful, meaning |
38 |
| - // that it has a State object (defined below) that contains fields that affect |
39 |
| - // how it looks. |
40 |
| - |
41 |
| - // This class is the configuration for the state. It holds the values (in this |
42 |
| - // case the title) provided by the parent (in this case the App widget) and |
43 |
| - // used by the build method of the State. Fields in a Widget subclass are |
44 |
| - // always marked "final". |
45 |
| - |
46 |
| - final String title; |
47 |
| - |
48 |
| - @override |
49 |
| - _MyHomePageState createState() => _MyHomePageState(); |
50 |
| -} |
51 |
| - |
52 |
| -class _MyHomePageState extends State<MyHomePage> { |
53 |
| - int _counter = 0; |
54 |
| - |
55 |
| - void _incrementCounter() { |
56 |
| - setState(() { |
57 |
| - // This call to setState tells the Flutter framework that something has |
58 |
| - // changed in this State, which causes it to rerun the build method below |
59 |
| - // so that the display can reflect the updated values. If we changed |
60 |
| - // _counter without calling setState(), then the build method would not be |
61 |
| - // called again, and so nothing would appear to happen. |
62 |
| - _counter++; |
63 |
| - }); |
64 |
| - } |
65 |
| - |
66 |
| - @override |
67 |
| - Widget build(BuildContext context) { |
68 |
| - // This method is rerun every time setState is called, for instance as done |
69 |
| - // by the _incrementCounter method above. |
70 |
| - // |
71 |
| - // The Flutter framework has been optimized to make rerunning build methods |
72 |
| - // fast, so that you can just rebuild anything that needs updating rather |
73 |
| - // than having to individually change instances of widgets. |
74 |
| - return Scaffold( |
75 |
| - appBar: AppBar( |
76 |
| - // Here we take the value from the MyHomePage object that was created by |
77 |
| - // the App.build method, and use it to set our appbar title. |
78 |
| - title: Text(widget.title), |
79 |
| - ), |
80 |
| - body: Center( |
81 |
| - // Center is a layout widget. It takes a single child and positions it |
82 |
| - // in the middle of the parent. |
83 |
| - child: Column( |
84 |
| - // Column is also a layout widget. It takes a list of children and |
85 |
| - // arranges them vertically. By default, it sizes itself to fit its |
86 |
| - // children horizontally, and tries to be as tall as its parent. |
87 |
| - // |
88 |
| - // Invoke "debug painting" (press "p" in the console, choose the |
89 |
| - // "Toggle Debug Paint" action from the Flutter Inspector in Android |
90 |
| - // Studio, or the "Toggle Debug Paint" command in Visual Studio Code) |
91 |
| - // to see the wireframe for each widget. |
92 |
| - // |
93 |
| - // Column has various properties to control how it sizes itself and |
94 |
| - // how it positions its children. Here we use mainAxisAlignment to |
95 |
| - // center the children vertically; the main axis here is the vertical |
96 |
| - // axis because Columns are vertical (the cross axis would be |
97 |
| - // horizontal). |
98 |
| - mainAxisAlignment: MainAxisAlignment.center, |
99 |
| - children: <Widget>[ |
100 |
| - Text( |
101 |
| - 'You have pushed the button this many times:', |
102 |
| - ), |
103 |
| - Text( |
104 |
| - '$_counter', |
105 |
| - style: Theme.of(context).textTheme.headline4, |
106 |
| - ), |
107 |
| - ], |
108 |
| - ), |
109 |
| - ), |
110 |
| - floatingActionButton: FloatingActionButton( |
111 |
| - onPressed: _incrementCounter, |
112 |
| - tooltip: 'Increment', |
113 |
| - child: Icon(Icons.add), |
114 |
| - ), // This trailing comma makes auto-formatting nicer for build methods. |
| 12 | + title: 'D Tree', |
| 13 | + home: Home(), |
115 | 14 | );
|
116 | 15 | }
|
117 | 16 | }
|
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