学习flutter的第一天

main1.dart

import 'package:flutter/material.dart';
import 'package:english_words/english_words.dart';

void main() => runApp(new MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final wordPair = new WordPair.random();
    return new MaterialApp(
      title: 'Welcome to Flutter',
      home: new RandomWords(),
      theme: new ThemeData(primaryColor: Colors.white),
    );
  }
}

// #docregion RandomWordsState, RWS-class-only
class RandomWordsState extends State<RandomWords> {
  final _saved = new Set<WordPair>();
  final _suggestions = <WordPair>[];
  final _biggerFont = const TextStyle(fontSize: 18.0);

  Widget _buildSuggestions() {
    return new ListView.builder(
      padding: const EdgeInsets.all(16.0),
      itemBuilder: (context, i) {
        if (i.isOdd) return new Divider();
        final index = i ~/ 2;
        if (index >= _suggestions.length) {
          _suggestions.addAll(generateWordPairs().take(10));
        }
        return _buildRow(_suggestions[index]);
      },
    );
  }

  /*跳转新页面*/
  void _pushSaved() {
    Navigator.of(context).push(new MaterialPageRoute(builder: (context) {
      final tiles = _saved.map((pair) {
        return new ListTile(
            title: new Text(
          pair.asPascalCase,
          style: _biggerFont,
        ));
      });
      final divided =
          ListTile.divideTiles(context: context, tiles: tiles).toList();

      return new Scaffold(
        appBar: new AppBar(
          title: new Text('saved suggestions'),
        ),
        body: new ListView(children: divided),
      );
    }));
  }

  /**
   *   跳转container
   */
  void _pushContainer() {
    Navigator.of(context).push(new MaterialPageRoute(builder: (context) {
      return new Scaffold(
        appBar: new AppBar(
          title: new Text('container；练习'),
        ),
        body: Center(
            child: Container(
          child: Text(
            '慕课网是IT学习技能平台',
            textAlign: TextAlign.right,
            style: TextStyle(
                fontSize: 25.0,
                color: Color.fromARGB(255, 255, 150, 150),
                decoration: TextDecoration.underline,
                decorationStyle: TextDecorationStyle.solid),
          ),
          alignment: Alignment.topLeft,
          width: 500.0,
          height: 400.0,
//          color: Colors.lightBlue,
          padding: const EdgeInsets.fromLTRB(10.0, 30.0, 0, 0),
          margin: const EdgeInsets.all(40.0),
          decoration: new BoxDecoration(
              gradient: const LinearGradient(colors: [
            Colors.lightBlue,
            Colors.lightGreen,
            Colors.purple
          ])),
        )),
      );
    }));
  }

  /**
   *  图片练习 2019年9月5日11:05:43
   */
  void _pushImage() {
    Navigator.of(context).push(new MaterialPageRoute(builder: (context) {
      return new Scaffold(
        appBar: new AppBar(
          title: new Text('container；练习'),
        ),
        body: Center(
            child: Container(
//          width: 300.0,
          height: 300.0,
          color: Colors.lightGreen,
          child: new Image.network(
            'http://juhuiwangluo.com/files/images/banner05.jpg',
            scale: 2.0,
            fit: BoxFit.cover,
            colorBlendMode: BlendMode.darken,
            repeat: ImageRepeat.repeat,
          ),
        )),
      );
    }));
  }

  // #enddocregion RWS-class-only
  @override
  Widget build(BuildContext context) {
//    final wordPair = WordPair.random();
//    return Text(wordPair.asPascalCase);
    return new Scaffold(
        appBar: new AppBar(
          title: new Text('start name generator'),
          actions: <Widget>[
            new IconButton(icon: new Icon(Icons.list), onPressed: _pushImage),
            new IconButton(icon: new Icon(Icons.list), onPressed: _pushSaved),
            new IconButton(
                icon: new Icon(Icons.list), onPressed: _pushContainer)
          ],
        ),
        body: _buildSuggestions());
  }

// #docregion RWS-class-only

  Widget _buildRow(WordPair pair) {
    final alreadySaved = _saved.contains(pair);
    return new ListTile(
      title: new Text(
        pair.asPascalCase,
        style: _biggerFont,
      ),
      trailing: new Icon(
        alreadySaved ? Icons.favorite : Icons.favorite_border,
        color: alreadySaved ? Colors.red : null,
      ),
      onTap: () {
        setState(() {
          if (alreadySaved) {
            _saved.remove(pair);
          } else {
            _saved.add(pair);
          }
        });
      },
    );
  }
}

// #docregion RandomWords
class RandomWords extends StatefulWidget {
  @override
  RandomWordsState createState() => RandomWordsState();
}