How to add "read more" in richtext()? – Flutter

i did it by myself,

1. divide the text by two (bagian1, bagian2)
2. use bagian1 as primary text and then bold
3. create myReadmore widget, return Container or "readmore"
4. return Column contains RichText and myReadmore

my code below:

import 'package:flutter/material.dart';

class BoldAsteris extends StatefulWidget {
  final String text;

  BoldAsteris({required this.text});

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

class _BoldAsterisState extends State<BoldAsteris> {
  // variable
  late bool isExpanded = false;
  late String bagian1;
  late String bagian2;

  @override
  void initState() {
    super.initState();

    // init for divide the text by two
    if (widget.text.length > 550 && isExpanded == false) {
      bagian1 = widget.text.substring(0, 550);
      bagian2 = widget.text.substring(551, widget.text.length);
    } else {
      bagian1 = widget.text;
      bagian2 = "";
    }
  }

  @override
  Widget build(BuildContext context) {

    // bold text between "*"
    String ubahAsteris = bagian1.replaceAll(RegExp(r'**'), "*");
    List<String> words = ubahAsteris.split('*');
    List<TextSpan> spans = List<TextSpan>.generate(words.length, (index) {
      if (index.isOdd) {
        return TextSpan(
          text: words[index],
          style: TextStyle(fontWeight: FontWeight.bold),
        );
      } else {
        return TextSpan(text: words[index]);
      }
    });

    // my Readmore widget
    Widget myReadmore() {
      return bagian2 == ""
          ? Container(
              height: 0,
            )
          : InkWell(
              child: Text('Baca selengkapnya', style: TextStyle(color: Colors.blue, fontSize: 17),),
              onTap: () {
                print('object');
                setState(() {
                  isExpanded = true;
                  bagian1 = widget.text;
                  bagian2 = "";
                });
              },
            );
    }

    // return Column -> RichText & readmore widget
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        RichText(
          softWrap: true,
          overflow: TextOverflow.clip,
          text: TextSpan(
              children: spans,
              style: TextStyle(color: Colors.black, fontSize: 17)),
        ),
        myReadmore() // my Readmore here !
      ],
    );
  }
}