我正在使用（下）创建一个简单的条形图，fl_chart并且需要使用图标作为 x 标题（而不是文本）。例如，用图标替换下面的0, 1, 2, 。3
下面是生成当前条形图的代码。是否可以添加图标/PNG 作为标题？getBottomTitles返回SideTitles哪个只能是字符串？
import 'package:fl_chart/fl_chart.dart';
import 'package:flutter/material.dart';
import 'bar_data.dart';
import 'package:fl_chart/fl_chart.dart';
import 'package:flutter/material.dart';
import 'bar_data.dart';
class BarChartWidget extends StatelessWidget {
final double barWidth = 50;
@override
Widget build(BuildContext context) => BarChart(
BarChartData(
alignment: BarChartAlignment.center,
maxY: 20,
minY: 0,
groupsSpace: 30,
borderData: FlBorderData(show: false),
barTouchData: BarTouchData(
enabled: true,
touchTooltipData: BarTouchTooltipData(
tooltipBgColor: Colors.white,
tooltipRoundedRadius: 8,
)
),
titlesData: FlTitlesData(
topTitles: BarTitles.getTopBottomTitles(),
bottomTitles: BarTitles.getTopBottomTitles(),
leftTitles: BarTitles.getSideTitles(),
rightTitles: BarTitles.getSideTitles(),
),
gridData: FlGridData(
drawHorizontalLine: false,
),
barGroups: BarData.barData
.map(
(data) => BarChartGroupData(
x: data.id,
showingTooltipIndicators: [0],
barRods: [
BarChartRodData(
y: data.y,
width: barWidth,
colors: [data.color],
borderRadius: data.y > 0
? const BorderRadius.only(
topLeft: Radius.circular(6),
topRight: Radius.circular(6),
)
: const BorderRadius.only(
bottomLeft: Radius.circular(6),
bottomRight: Radius.circular(6),
),
),
],
),
)
.toList(),
),
);
}