Flutter富文本编辑插件rich_text_composer的使用

Flutter富文本编辑插件rich_text_composer的使用

有时候使用RichText进行富文本编辑可能会比较复杂。RichTextComposer插件可以帮助我们简化这种过程。通过使用RichTextComposer，我们可以将复杂的RichText代码简化为更易读的形式。

示例代码

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

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('RichText Composer 示例'),
        ),
        body: RichTextEditor(),
      ),
    );
  }
}

class RichTextEditor extends StatefulWidget {
  @override
  _RichTextEditorState createState() => _RichTextEditorState();
}

class _RichTextEditorState extends State<RichTextEditor> {
  String weatherType = 'Sunny';
  String temperatureMax = '30°C';

  @override
  Widget build(BuildContext context) {
    return Center(
      child: RichTextComposer(
        text: "The forecast for today is @weatherType with a high of @high",
        richTextBuilders: [
          RichTextPatternBuilder(
            pattern: RegExp(r'@weatherType'), // 使用正则表达式匹配特定模式
            builder: (
              text, {
              required int endIndex,
              required int matchIndex,
              required int startIndex,
            }) {
              return TextSpan(text: weatherType, style: TextStyle(fontWeight: FontWeight.bold));
            },
          ),
          RichTextPatternBuilder(
            pattern: RegExp(r'@high'), // 使用正则表达式匹配特定模式
            builder: (
              text, {
              required int endIndex,
              required int matchIndex,
              required int startIndex,
            }) {
              return TextSpan(text: temperatureMax, style: TextStyle(color: Colors.red));
            },
          ),
        ],
        plainTextBuilder: (text) => TextSpan(
          text: text,
          style: TextStyle(color: Colors.black)
        ),
      ),
    );
  }
}

解释

1. 导入必要的库:

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

2. 定义主应用类:

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

3. 定义应用界面:

   class MyApp extends StatelessWidget {
     @override
     Widget build(BuildContext context) {
       return MaterialApp(
         home: Scaffold(
           appBar: AppBar(
             title: Text('RichText Composer 示例'),
           ),
           body: RichTextEditor(),
         ),
       );
     }
   }
   

4. 定义富文本编辑器状态类:

   class RichTextEditor extends StatefulWidget {
     @override
     _RichTextEditorState createState() => _RichTextEditorState();
   }
   

5. 定义富文本编辑器状态:

   class _RichTextEditorState extends State<RichTextEditor> {
     String weatherType = 'Sunny'; // 天气类型
     String temperatureMax = '30°C'; // 最高温度
   
     @override
     Widget build(BuildContext context) {
       return Center(
         child: RichTextComposer(
           text: "The forecast for today is @weatherType with a high of @high", // 要渲染的文本
           richTextBuilders: [ // 定义如何处理特定模式的文本
             RichTextPatternBuilder(
               pattern: RegExp(r'@weatherType'), // 使用正则表达式匹配特定模式
               builder: (
                 text, {
                 required int endIndex,
                 required int matchIndex,
                 required int startIndex,
               }) {
                 return TextSpan(text: weatherType, style: TextStyle(fontWeight: FontWeight.bold));
               },
             ),
             RichTextPatternBuilder(
               pattern: RegExp(r'@high'), // 使用正则表达式匹配特定模式
               builder: (
                 text, {
                 required int endIndex,
                 required int matchIndex,
                 required int startIndex,
               }) {
                 return TextSpan(text: temperatureMax, style: TextStyle(color: Colors.red));
               },
             ),
           ],
           plainTextBuilder: (text) => TextSpan(
             text: text,
             style: TextStyle(color: Colors.black)
           ),
         ),
       );
     }
   }