Slider Value Indicator remains visible when using SliderThemeData.ShowValueIndicator.onDrag

Steps to reproduce

Run the below official code sample with a SliderTheme
Notice when you stop the drag (Touch not in contact with screen) the value indicator is still visible

Expected results

The Value Indicator should be hidden if the touch is not in contact with screen or when not dragging.

Screen.Recording.2026-01-09.at.3.21.04.PM.mov

Actual results

The Value Indicator is always shown which is same behavior as

showValueIndicator: ShowValueIndicator.alwaysVisible

but as per docs of ShowValueIndicator.onDrag

The value indicator is shown while dragging.

Code sample

import 'package:flutter/material.dart';

/// Flutter code sample for [Slider].

void main() => runApp(const SliderApp());

class SliderApp extends StatelessWidget {
  const SliderApp({super.key});

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(home: SliderExample());
  }
}

class SliderExample extends StatefulWidget {
  const SliderExample({super.key});

  @override
  State<SliderExample> createState() => _SliderExampleState();
}

class _SliderExampleState extends State<SliderExample> {
  double _currentSliderPrimaryValue = 0.2;
  double _currentSliderSecondaryValue = 0.5;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Slider')),
      body: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: <Widget>[
          SliderTheme(
            data: SliderTheme.of(context).copyWith(
              valueIndicatorShape: IV4RoundValueIndicator(),
              showValueIndicator: ShowValueIndicator.onDrag,
              trackHeight: 1,
            ),
            child: Slider(
              value: _currentSliderSecondaryValue,
              label: _currentSliderSecondaryValue.round().toString(),
              onChanged: (double value) {
                setState(() {
                  _currentSliderSecondaryValue = value;
                });
              },
            ),
          ),
        ],
      ),
    );
  }
}

class IV4RoundValueIndicator extends SliderComponentShape {
  @override
  Size getPreferredSize(bool isEnabled, bool isDiscrete) {
    return Size(40, 40); // Size of the value indicator
  }

  @override
  void paint(
    PaintingContext context,
    Offset center, {
    required Animation<double> activationAnimation,
    required Animation<double> enableAnimation,
    required bool isDiscrete,
    required TextPainter labelPainter,
    required RenderBox parentBox,
    required SliderThemeData sliderTheme,
    required TextDirection textDirection,
    required double value,
    required double textScaleFactor,
    required Size sizeWithOverflow,
  }) {
    final canvas = context.canvas;

    // Define the circle indicator parameters
    const double circleDiameter = 44.0;
    final Offset circleCenter = Offset(
      center.dx,
      center.dy - circleDiameter - 10,
    );

    final paint = Paint()
      ..color = sliderTheme.valueIndicatorColor ?? Colors.purple
      ..style = PaintingStyle.fill;

    // Draw the circle
    canvas.drawCircle(circleCenter, circleDiameter / 2, paint);

    // Draw the text centered in the circle
    final textOffset = Offset(
      circleCenter.dx - (labelPainter.width / 2),
      circleCenter.dy - (labelPainter.height / 2),
    );
    labelPainter.paint(canvas, textOffset);
  }
}

Screenshots or Video

Screenshots / Video demonstration

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Logs

Flutter Doctor output

I found this on latest flutter stable but I believe this reproduces on latest master too.

Doctor output

[✓] Flutter (Channel stable, 3.38.5, on macOS 26.2 25C56 darwin-arm64, locale en-US) [979ms]
    • Flutter version 3.38.5 on channel stable at /Users/maheshjamdade/Development/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision f6ff1529fd (4 weeks ago), 2025-12-11 11:50:07 -0500
    • Engine revision 1527ae0ec5
    • Dart version 3.10.4
    • DevTools version 2.51.1
    • Feature flags: enable-web, enable-linux-desktop, enable-macos-desktop, enable-windows-desktop, enable-android,
      enable-ios, cli-animations, enable-native-assets, omit-legacy-version-file, enable-lldb-debugging