Add text widget to getDrawingHorizontalLine in fl_chart - flutter

Question

This is my fl_chart bar chart.
I need to add the 'AVG' text to the line as in the image below.
Any ideas? Really stuck. The line is returned under "getDrawingHorizontalLine" section below.
I could try and figure out where this line is and use a stack but doesn't sound too promising 🤔
return BarChart(
BarChartData(
barGroups: graphData,
alignment: BarChartAlignment.center,
groupsSpace: isPortrait ? null : 70,
minY: 0,
maxY: maxUsage,
gridData: FlGridData(
horizontalInterval: average,
checkToShowHorizontalLine: (value) => value == average, <----- draw when avg
drawHorizontalLine: true,
drawVerticalLine: false,
getDrawingHorizontalLine: (value) => FlLine( <------ draws the line
color: Colors.white,
strokeWidth: 1,
dashArray: [5, 5],
),
),

Answer 1

I ended up adding it to the right titles and showing it when value == the value I want it to show.
static AxisTitles getRightTitles(isOverlay, maxUsage, averageUsage) => AxisTitles(
sideTitles: SideTitles(
interval: 0.9,
showTitles: isOverlay,
reservedSize: 34,
getTitlesWidget: (value, meta) {
final String avg = averageUsage.toStringAsFixed(0);
final String val = value.toStringAsFixed(0);
final bool show = (avg == val);
return isOverlay && show
? const Padding(
padding: EdgeInsets.only(left: 8.0, top: 3),
child: Text(
'AVG',
maxLines: 1,
softWrap: false,
style: TextStyle(
color: Colors.white,
fontSize: 11,
fontWeight: FontWeight.bold,
),
),
)
: const SizedBox();
},
),
);