pie_chart_sample2.dart

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

import 'indicator.dart';

class PieChartSample2 extends StatefulWidget {
  @override
  State<StatefulWidget> createState() => PieChart2State();
}

class PieChart2State extends State {
  int touchedIndex;

  @override
  Widget build(BuildContext context) {
    return AspectRatio(
      aspectRatio: 1.3,
      child: Card(
        color: Colors.white,
        child: Row(
          children: <Widget>[
            const SizedBox(
              height: 18,
            ),
            Expanded(
              child: AspectRatio(
                aspectRatio: 1,
                child: PieChart(
                  PieChartData(
                      pieTouchData: PieTouchData(touchCallback: (pieTouchResponse) {
                        setState(() {
                          if (pieTouchResponse.touchInput is FlLongPressEnd ||
                              pieTouchResponse.touchInput is FlPanEnd) {
                            touchedIndex = -1;
                          } else {
                            touchedIndex = pieTouchResponse.touchedSectionIndex;
                          }
                        });
                      }),
                      borderData: FlBorderData(
                        show: false,
                      ),
                      sectionsSpace: 0,
                      centerSpaceRadius: 40,
                      sections: showingSections()),
                ),
              ),
            ),
            Column(
              mainAxisSize: MainAxisSize.max,
              mainAxisAlignment: MainAxisAlignment.end,
              crossAxisAlignment: CrossAxisAlignment.start,
              children: const <Widget>[
                Indicator(
                  color: Color(0xff0293ee),
                  text: 'First',
                  isSquare: true,
                ),
                SizedBox(
                  height: 4,
                ),
                Indicator(
                  color: Color(0xfff8b250),
                  text: 'Second',
                  isSquare: true,
                ),
                SizedBox(
                  height: 4,
                ),
                Indicator(
                  color: Color(0xff845bef),
                  text: 'Third',
                  isSquare: true,
                ),
                SizedBox(
                  height: 4,
                ),
                Indicator(
                  color: Color(0xff13d38e),
                  text: 'Fourth',
                  isSquare: true,
                ),
                SizedBox(
                  height: 18,
                ),
              ],
            ),
            const SizedBox(
              width: 28,
            ),
          ],
        ),
      ),
    );
  }

  List<PieChartSectionData> showingSections() {
    return List.generate(4, (i) {
      final isTouched = i == touchedIndex;
      final double fontSize = isTouched ? 25 : 16;
      final double radius = isTouched ? 60 : 50;
      switch (i) {
        case 0:
          return PieChartSectionData(
            color: const Color(0xff0293ee),
            value: 40,
            title: '40%',
            radius: radius,
            titleStyle: TextStyle(
                fontSize: fontSize, fontWeight: FontWeight.bold, color: const Color(0xffffffff)),
          );
        case 1:
          return PieChartSectionData(
            color: const Color(0xfff8b250),
            value: 30,
            title: '30%',
            radius: radius,
            titleStyle: TextStyle(
                fontSize: fontSize, fontWeight: FontWeight.bold, color: const Color(0xffffffff)),
          );
        case 2:
          return PieChartSectionData(
            color: const Color(0xff845bef),
            value: 15,
            title: '15%',
            radius: radius,
            titleStyle: TextStyle(
                fontSize: fontSize, fontWeight: FontWeight.bold, color: const Color(0xffffffff)),
          );
        case 3:
          return PieChartSectionData(
            color: const Color(0xff13d38e),
            value: 15,
            title: '15%',
            radius: radius,
            titleStyle: TextStyle(
                fontSize: fontSize, fontWeight: FontWeight.bold, color: const Color(0xffffffff)),
          );
        default:
          return null;
      }
    });
  }
}