Robo-advisory-dart/lib/screens/home/local_widgets/expenses_chart.dart

import 'package:fl_chart/fl_chart.dart';
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:robo_advisory/providers/transaction_provider.dart';
import 'package:robo_advisory/providers/user_provider.dart';

class ExpensesChart extends StatefulWidget {
  @override
  State<StatefulWidget> createState() => ExpensesChartState();
}

class ExpensesChartState extends State {
  int touchedIndex;

  @override
  Widget build(BuildContext context) {
    List<String> categories =
        Provider.of<UserProvider>(context, listen: true).categories;
    return Row(
      children: <Widget>[
        Expanded(
          child: PieChart(
            PieChartData(
                pieTouchData: PieTouchData(touchCallback: (pieTouchResponse) {
                  setState(() {
                    if (pieTouchResponse.touchInput is FlLongPressEnd ||
                        pieTouchResponse.touchInput is FlPanEnd) {
                      touchedIndex = -1;
                    } else {
                      touchedIndex = pieTouchResponse.touchedSectionIndex;
                      if (touchedIndex != null) {
                        Provider.of<UserProvider>(context, listen: false)
                            .setSelectedTabIndex(3);
                        Provider.of<TransactionProvider>(context, listen: false)
                            .setSelectedCategory(categories[touchedIndex + 1]);
                      }
                    }
                  });
                }),
                borderData: FlBorderData(
                  show: false,
                ),
                sectionsSpace: 1,
                centerSpaceRadius: 70,
                sections: showingSections()),
          ),
        ),
      ],
    );
  }

  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: 50,
            title: '50%',
            radius: radius,
            titleStyle: TextStyle(
                fontSize: fontSize,
                fontWeight: FontWeight.bold,
                color: const Color(0xffffffff)),
          );
        case 1:
          return PieChartSectionData(
            color: const Color(0xfff8b250),
            value: 12,
            title: '12%',
            radius: radius,
            titleStyle: TextStyle(
                fontSize: fontSize,
                fontWeight: FontWeight.bold,
                color: const Color(0xffffffff)),
          );
        case 2:
          return PieChartSectionData(
            color: const Color(0xff13d38e),
            value: 13,
            title: '13%',
            radius: radius,
            titleStyle: TextStyle(
                fontSize: fontSize,
                fontWeight: FontWeight.bold,
                color: const Color(0xffffffff)),
          );
        case 3:
          return PieChartSectionData(
            color: const Color(0xff845bef),
            value: 25,
            title: '25%',
            radius: radius,
            titleStyle: TextStyle(
                fontSize: fontSize,
                fontWeight: FontWeight.bold,
                color: const Color(0xffffffff)),
          );
        default:
          return null;
      }
    });
  }
}