syncfusion_flutter_gauges 值变化不更新指针

Question

使用仪表图显示实时数据变化，但指针不会随着值的变化而更新，它只显示第一个值。

analytics.dart

import 'package:my_app/widgets/charts/gauge.dart';

// class _AnalyticsPageState extends State<AnalyticsPage> {
@override
  void initState() {
    super.initState();
    _timer = Timer.periodic(const Duration(seconds: 1), (timer) {
      _liveCurrent = randomNumber(dValue: true);
      _liveVoltage = randomNumber();
    });
  }

// usage
return Gauge(
  title: 'Voltage',
  pointer: _liveVoltage,
  minValue: 0,
  maxValue: 150,
  scales: [
    GaugeRange(
      startValue: 0,
      endValue: 50,
      color: Colors.green,
    ),
    GaugeRange(
      startValue: 50,
      endValue: 100,
      color: Colors.orange,
    ),
    GaugeRange(
      startValue: 100,
      endValue: 150,
      color: Colors.red,
    )
  ],
),

图表在

my_app/widgets/charts/gauge.dart

中定义

class Gauge extends StatefulWidget {

  final String? title;
  final List<GaugeRange> scales;
  final double pointer;
  final double minValue;
  final double maxValue;

  const Gauge({
    Key? key,
    this.title,
    required this.scales,
    this.pointer = 0,
    this.minValue = 0,
    this.maxValue = 100
  }) : super(key: key);

  @override
  State<Gauge> createState() => _GaugeState();
}

class _GaugeState extends State<Gauge> {

  Widget _getRadialGauge() {
    return SfRadialGauge(
        title: GaugeTitle(
            text: widget.title!,
            textStyle: const TextStyle(
                fontSize: 20.0,
                fontWeight: FontWeight.bold
            )
        ),
        axes: <RadialAxis>[
          RadialAxis(
              minimum: widget.minValue,
              maximum: widget.maxValue,
              ranges: widget.scales,
              pointers: <GaugePointer>[
                NeedlePointer(
                    value: widget.pointer
                )
              ],
              annotations: <GaugeAnnotation>[
                GaugeAnnotation(
                    widget: Text(
                        widget.pointer.toStringAsFixed(2),
                        style: const TextStyle(
                            fontSize: 25,
                            fontWeight: FontWeight.bold
                        )
                    ),
                    angle: 90,
                    positionFactor: 0.5
                )
              ]
          )
        ]
    );
  }

  @override
  Widget build(BuildContext context) {
    return _getRadialGauge();
  }
}

我想让

widget.pointer

值动态化，并在父窗口小部件中更改值时更改指针

Analytics

.