String _exampleCode =
      "class MyHomePage extends StatefulWidget { MyHomePage({Key key, this.title}) : super(key: key); final String title; @override _MyHomePageState createState() => _MyHomePageState();}";

final SyntaxHighlighterStyle style =
        Theme.of(context).brightness == Brightness.dark
            ? SyntaxHighlighterStyle.darkThemeStyle()
            : SyntaxHighlighterStyle.lightThemeStyle();

            RichText(
              text: TextSpan(
                style: const TextStyle(fontFamily: 'monospace', fontSize: 10.0),
                children: <TextSpan>[
                  DartSyntaxHighlighter(style).format(_exampleCode),
                ],
              ),

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

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

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Syntax Highlighter Example',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Syntax Highlighter Example'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);
  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  String _exampleCode =
      "class MyHomePage extends StatefulWidget { MyHomePage({Key key, this.title}) : super(key: key); final String title; @override _MyHomePageState createState() => _MyHomePageState();}";

  @override
  Widget build(BuildContext context) {
    final SyntaxHighlighterStyle style =
        Theme.of(context).brightness == Brightness.dark
            ? SyntaxHighlighterStyle.darkThemeStyle()
            : SyntaxHighlighterStyle.lightThemeStyle();
    return Scaffold(
        appBar: AppBar(
          title: Text(widget.title),
        ),
        body: SingleChildScrollView(
          child: Padding(
            padding: const EdgeInsets.all(16.0),
            child: RichText(
              text: TextSpan(
                style: const TextStyle(fontFamily: 'monospace', fontSize: 10.0),
                children: <TextSpan>[
                  DartSyntaxHighlighter(style).format(_exampleCode),
                ],
              ),
            ),
          ),
        ));
  }
}