fix: keep dock drag springs live and add elastic leading-edge pull

README.md

@@ -1,10 +1,10 @@
 # TPSchedule
 
-当前Android版本0.7.8+30：增强点按挤压回弹、整条Dock随拖动方向弹动、图标到位动画及乳白折射光泽，见[本次记录](docs/tpschedule-0.7.8-dock-spring.md)。构建29提供Dock点按/拖动弹性与Android平板横竖屏、分屏适配，见[本次验证记录](docs/tpschedule-0.7.8-dock-tablet.md)。构建28已提前建立通知类别、区分通知总开关和类别状态，见[通知排查记录](docs/tpschedule-0.7.8-notification-permissions.md)。用户手机已通过开启通知权限并重测确认恢复后台通知。Dock乳白透光层和边缘折射继续保留，见[材质优化记录](docs/tpschedule-0.7.8-dock-refinement.md)。本科/研究生HTML反馈见[0.7.8功能记录](docs/tpschedule-0.7.8-validation.md)及[反馈服务说明](server/feedback/html-diagnostic-update.md)，更新管理后台见[部署说明](server/updates/README.md)。
+当前Android版本0.7.8+31：滑块移动中持续Q弹、前缘牵拉和弹性跟随，玻璃材质减薄，见[本次记录](docs/tpschedule-0.7.8-dock-drag.md)。构建30提供增强点按挤压回弹、整条Dock随拖动方向弹动、图标到位动画及乳白折射光泽，见[本次记录](docs/tpschedule-0.7.8-dock-spring.md)。构建29提供Dock点按/拖动弹性与Android平板横竖屏、分屏适配，见[本次验证记录](docs/tpschedule-0.7.8-dock-tablet.md)。构建28已提前建立通知类别、区分通知总开关和类别状态，见[通知排查记录](docs/tpschedule-0.7.8-notification-permissions.md)。用户手机已通过开启通知权限并重测确认恢复后台通知。Dock乳白透光层和边缘折射继续保留，见[材质优化记录](docs/tpschedule-0.7.8-dock-refinement.md)。本科/研究生HTML反馈见[0.7.8功能记录](docs/tpschedule-0.7.8-validation.md)及[反馈服务说明](server/feedback/html-diagnostic-update.md)，更新管理后台见[部署说明](server/updates/README.md)。
 
 0.7.0补充：考试页查询类型与卡片保持16像素间距；反馈问题和建议可自选附带最近10分钟的登录/读取/提醒诊断日志。默认不发送，不含密码、Cookie或课表内容，单独作为邮件文本附件。服务端需按[日志附件更新说明](server/feedback/diagnostic-log-update.md)手动更新；真实学校登录及SMTP未由本次离线测试代替验证。玻璃取样偏移仍在调查，未纳入本次修复结论。
 
-学生课表 APP，Flutter 实现，支持电子科技大学研究生和本科生系统。Android 0.7.8+30，Android 7.0 及以上。
+学生课表 APP，Flutter 实现，支持电子科技大学研究生和本科生系统。Android 0.7.8+31，Android 7.0 及以上。
 
 使用用户提供的原始 SVG 图标，蓝色渐变、黄色日历框及白色笔画保持一致；启动画面使用相同配色。0.5.1修复重复启动页闪烁：初始化期间保留原生启动屏，数据就绪后直接显示课表首帧，不再叠加Flutter品牌页或淡出动画。Android12+ 原生启动屏使用同色纯蓝背景及图标，旧版采用蓝色渐变。
 

docs/android-mvp-validation.md

@@ -1,6 +1,6 @@
 # Android 首版验证记录
 
-当前版本为0.7.8+30，点按/方向弹动及乳白材质见[本次记录](tpschedule-0.7.8-dock-spring.md)。构建29的Dock弹性与Android平板验证见[本次记录](tpschedule-0.7.8-dock-tablet.md)。构建28的通知权限恢复、通道初始化及真实后台触发见[通知记录](tpschedule-0.7.8-notification-permissions.md)。Dock乳白透光材质见[优化记录](tpschedule-0.7.8-dock-refinement.md)。本科/研究生HTML反馈及签名、备案信息见[0.7.8功能记录](tpschedule-0.7.8-validation.md)。应用更新检查与后台说明见[0.7.6记录](tpschedule-0.7.6-updates.md)。本科考试兼容的验证见[0.7.5记录](tpschedule-0.7.5-validation.md)。两例真实课表缺失字段问题待新页面定位。本科接入记录见[0.7.0记录](tpschedule-0.7.0-validation.md)。下文为首版历史记录。
+当前版本为0.7.8+31，移动中Q弹、牵拉及减薄见[本次记录](tpschedule-0.7.8-dock-drag.md)。构建30的点按/方向弹动及乳白材质见[本次记录](tpschedule-0.7.8-dock-spring.md)。构建29的Dock弹性与Android平板验证见[本次记录](tpschedule-0.7.8-dock-tablet.md)。构建28的通知权限恢复、通道初始化及真实后台触发见[通知记录](tpschedule-0.7.8-notification-permissions.md)。Dock乳白透光材质见[优化记录](tpschedule-0.7.8-dock-refinement.md)。本科/研究生HTML反馈及签名、备案信息见[0.7.8功能记录](tpschedule-0.7.8-validation.md)。应用更新检查与后台说明见[0.7.6记录](tpschedule-0.7.6-updates.md)。本科考试兼容的验证见[0.7.5记录](tpschedule-0.7.5-validation.md)。两例真实课表缺失字段问题待新页面定位。本科接入记录见[0.7.0记录](tpschedule-0.7.0-validation.md)。下文为首版历史记录。
 
 日期：2026-10-13。测试环境：Flutter 3.47.7 / Dart 3.13.5 / JDK 17；Android 16 API 36，Pixel 7 模拟器，1080×2400。首版版本 0.1.0+1，包 ID com.example.hepan_everyday，最低 Android 7.0（API 24）。
 

docs/tpschedule-0.7.8-dock-drag.md

@@ -0,0 +1,24 @@
+# 0.7.8+31 拖动牵拉与轻薄玻璃
+
+用户要求拖动过程中也有持续的Q弹形变，并减薄玻璃；随后提供飞书20261028-114548.mp4，参考其中滑块、底座前缘被牵动和反向回弹的效果。本轮按已授权的直接执行方式完成。
+
+## 改动
+
+- 滑块以680/28的弹簧轴追随手指目标，有少量弹性滞后；释放时仍按手指最终位置选择标签，避免视觉滞后选错。重新抓取与取消继承可见速度。
+- 拖动输入唤醒620ms有限形变波，移动过程中横向伸缩、纵向挤压，后续输入可续发；暂停后自然结束，静止时不无限播放。按压、松手和减少动画状态调制形变强度。
+- 整条Dock随方向移动约8逻辑像素，并沿前缘额外伸展约6逻辑像素；反向时沿弹簧回收。图标和文字随底座位置移动，保持清晰，原到位动画继续。
+- 乳白层由38%/24%/30%减至29%/17%/23%；静止灰色滑块减轻，外缘柔光描边2.8降至1.8、内缘0.7降至0.45；阴影和折射高光减弱，保留轻模糊与折射。高度仍58，不改变点击区域及平板布局。
+
+## 连续拖动的关键修正
+
+逐帧预览发现，反复对同一控制器调用animateWith会在持续输入时重启计时，可能反复画出t=0，导致跟随几乎不移动。改为单一持续Ticker同时积分两个弹簧轴，触摸只更新目标。积分子步长不超过1/120秒，帧间隔封顶0.25秒；两个轴稳定后停表，减少动画及销毁时停止。无后台常驻动画。
+
+新增匀速连续拖动的中心实际位移断言，修正前失败、修正后通过；不是仅检查有无放大。另有牵拉滞后、前缘不对称伸展、移动中横纵形变和变薄透光层的RED→GREEN验证。
+
+## 验证与交付
+
+320项Flutter测试通过，静态分析无问题。保留点按弹性、快速反向点按连续性、图标悬停及松手衔接、取消归位、减少动画和平板/分屏回归。
+
+已逐帧检查右拖、左拖、反向、释放的渲染预览。独立审查未发现新的重要缺陷；持续Ticker的积分、生命周期与降动态路径另行复核通过。预览为Flutter渲染示意，本轮未作实体平板性能测试。
+
+APK为0.7.8、构建31，原包名、签名、密钥及备案号保留。旧APK、旧源码和0.5.4登记冻结文件校验保持。服务器无需更新代码；更新后台发布版本0.7.8、构建号31和对应HTTPS下载地址。

mobile/lib/app/app_version.dart

@@ -1,3 +1,3 @@
 const appVersion = '0.7.8';
-const appBuildNumber = 30;
+const appBuildNumber = 31;
 const appFilingNumber = '蜀ICP备2025169276号-5A';

mobile/lib/widgets/glass_dock.dart

@@ -3,6 +3,7 @@ import 'dart:ui' as ui;
 
 import 'package:flutter/material.dart';
 import 'package:flutter/physics.dart';
+import 'package:flutter/scheduler.dart';
 
 import 'glass_refraction.dart';
 
@@ -38,19 +39,91 @@ class _GlassDockState extends State<GlassDock> with TickerProviderStateMixin {
   late final AnimationController _sway = AnimationController.unbounded(
     vsync: this,
   );
+  late final AnimationController _ripple = AnimationController(
+    vsync: this,
+    duration: const Duration(milliseconds: 620),
+  );
+  void _wakeRipple() {
+    if (!_reduceMotion && !_ripple.isAnimating) _ripple.forward(from: 0);
+  }
+
+  double _swayTarget = 0, _swayVelocity = 0, _dragTarget = 0, _dragVelocity = 0;
+  Duration? _elasticLastTick;
+  late final Ticker _elasticTicker = createTicker(_tickElastic);
+  void _startElastic() {
+    if (!_elasticTicker.isActive) {
+      _elasticLastTick = null;
+      _elasticTicker.start();
+    }
+  }
+
+  // Keep one clock alive while input changes its targets. Restarting a spring
+  // on every pointer event repeatedly paints t=0 under continuous dragging.
+  void _tickElastic(Duration elapsed) {
+    final seconds = _elasticLastTick == null
+        ? 1 / 60
+        : ((elapsed - _elasticLastTick!).inMicroseconds / 1000000).clamp(
+            0.0,
+            0.25,
+          );
+    _elasticLastTick = elapsed;
+    final sway = _advanceSpring(
+      _sway.value,
+      _swayVelocity,
+      _swayTarget,
+      220,
+      18,
+      seconds,
+    );
+    final drag = _advanceSpring(
+      _dragFollow.value,
+      _dragVelocity,
+      _dragTarget,
+      680,
+      28,
+      seconds,
+    );
+    _swayVelocity = sway.$2;
+    _dragVelocity = drag.$2;
+    _sway.value = sway.$1;
+    _dragFollow.value = drag.$1;
+    if ((_sway.value - _swayTarget).abs() < 0.0005 &&
+        _swayVelocity.abs() < 0.005 &&
+        (_dragFollow.value - _dragTarget).abs() < 0.0005 &&
+        _dragVelocity.abs() < 0.005) {
+      _sway.value = _swayTarget;
+      _dragFollow.value = _dragTarget;
+      _swayVelocity = _dragVelocity = 0;
+      _elasticTicker.stop();
+      _elasticLastTick = null;
+    }
+  }
+
+  (double, double) _advanceSpring(
+    double value,
+    double velocity,
+    double target,
+    double stiffness,
+    double damping,
+    double seconds,
+  ) {
+    final steps = math.max(1, (seconds * 120).ceil());
+    final step = seconds / steps;
+    for (var i = 0; i < steps; i++) {
+      velocity += (stiffness * (target - value) - damping * velocity) * step;
+      value += velocity * step;
+    }
+    return (value, velocity);
+  }
+
   void _swayTo(double target) {
+    _swayTarget = _reduceMotion ? 0 : target;
     if (_reduceMotion) {
       _sway.value = 0;
+      _swayVelocity = 0;
       return;
     }
-    _sway.animateWith(
+    _startElastic();
-      SpringSimulation(
-        const SpringDescription(mass: 1, stiffness: 220, damping: 18),
-        _sway.value,
-        target,
-        _sway.velocity.clamp(-12, 12),
-      ),
-    );
   }
 
   bool _reduceMotion = false;
@@ -59,6 +132,7 @@ class _GlassDockState extends State<GlassDock> with TickerProviderStateMixin {
   void initState() {
     super.initState();
     _targetIndex = widget.selectedIndex;
+    _dragTarget = widget.selectedIndex.toDouble();
   }
 
   double get _pressure => _press.value.clamp(0.0, 1.18);
@@ -85,13 +159,34 @@ class _GlassDockState extends State<GlassDock> with TickerProviderStateMixin {
       _motion.value = widget.selectedIndex.toDouble();
       _press.value = 0;
       _tap.value = 0;
+      _ripple.value = 0;
+      _elasticTicker.stop();
+      _elasticLastTick = null;
+      _swayTarget = _swayVelocity = _dragVelocity = 0;
+      _dragTarget = _drag ?? widget.selectedIndex.toDouble();
+      _dragFollow.value = _drag ?? widget.selectedIndex.toDouble();
       _sway.value = 0;
     }
   }
 
+  late final AnimationController _dragFollow = AnimationController.unbounded(
+    vsync: this,
+    value: widget.selectedIndex.toDouble(),
+  );
+  void _followDragTo(double target) {
+    _dragTarget = target;
+    if (_reduceMotion) {
+      _dragFollow.value = target;
+      _dragVelocity = 0;
+      return;
+    }
+    _startElastic();
+  }
+
   double? _drag;
   double _dragSpeed = 0;
-  double get _position => _drag ?? _motion.value.clamp(-0.12, 2.12);
+  double get _position =>
+      (_drag != null ? _dragFollow.value : _motion.value).clamp(-0.12, 2.12);
   void _moveTo(int index, {double velocity = 0, bool springyTap = false}) {
     _targetIndex = index;
     if (_reduceMotion) {
@@ -140,10 +235,13 @@ class _GlassDockState extends State<GlassDock> with TickerProviderStateMixin {
 
   @override
   void dispose() {
+    _elasticTicker.dispose();
     _motion.dispose();
     _press.dispose();
     _tap.dispose();
     _sway.dispose();
+    _ripple.dispose();
+    _dragFollow.dispose();
     super.dispose();
   }
 
@@ -159,25 +257,25 @@ class _GlassDockState extends State<GlassDock> with TickerProviderStateMixin {
             colors: lens
                 ? [
                     Color.lerp(
-                      const Color(0xFFA1A4AA).withValues(alpha: 0.34),
+                      const Color(0xFFA1A4AA).withValues(alpha: 0.28),
                       const Color(0xFFD8DBE0).withValues(alpha: 0.0252),
                       pressure,
                     )!,
                     Color.lerp(
-                      const Color(0xFF8E939B).withValues(alpha: 0.26),
+                      const Color(0xFF8E939B).withValues(alpha: 0.21),
                       const Color(0xFFC3C7CE).withValues(alpha: 0.0144),
                       pressure,
                     )!,
                     Color.lerp(
-                      const Color(0xFFB4B7BC).withValues(alpha: 0.32),
+                      const Color(0xFFB4B7BC).withValues(alpha: 0.26),
                       const Color(0xFFE5E7EB).withValues(alpha: 0.0216),
                       pressure,
                     )!,
                   ]
                 : [
-                    Colors.white.withValues(alpha: 0.38),
+                    Colors.white.withValues(alpha: 0.29),
-                    const Color(0xFFFDFEFF).withValues(alpha: 0.24),
+                    const Color(0xFFFDFEFF).withValues(alpha: 0.17),
-                    Colors.white.withValues(alpha: 0.30),
+                    Colors.white.withValues(alpha: 0.23),
                   ],
           ),
         ),
@@ -187,7 +285,7 @@ class _GlassDockState extends State<GlassDock> with TickerProviderStateMixin {
     return ClipRRect(
       borderRadius: BorderRadius.circular(40),
       child: GlassRefraction(
-        strength: lens ? 0.78 + pressure * 0.70 : 1.14,
+        strength: lens ? 0.78 + pressure * 0.70 : 0.98,
         blurSigma: lens ? 1.6 - pressure * 0.6 : 1.5,
         child: content,
       ),
@@ -202,7 +300,14 @@ class _GlassDockState extends State<GlassDock> with TickerProviderStateMixin {
         MediaQuery.sizeOf(context).width >= 600 ? 300.0 : 264.0,
       );
       return AnimatedBuilder(
-        animation: Listenable.merge([_motion, _press, _tap, _sway]),
+        animation: Listenable.merge([
+          _motion,
+          _press,
+          _tap,
+          _sway,
+          _ripple,
+          _dragFollow,
+        ]),
         builder: (context, _) {
           final press = _pressure;
           final pulse = _reduceMotion ? 0.0 : math.sin(math.pi * _tap.value);
@@ -213,21 +318,34 @@ class _GlassDockState extends State<GlassDock> with TickerProviderStateMixin {
               : math.sin(2 * math.pi * _tap.value);
           final tapStretch = tapWave >= 0 ? tapWave * 0.24 : tapWave * 0.065;
           final tapRise = tapWave >= 0 ? -tapWave * 0.045 : -tapWave * 0.15;
+          // Pointer movement wakes a finite ripple; pauses do not start idle loops.
+          final dragWave = _reduceMotion
+              ? 0.0
+              : math.sin(2 * math.pi * _ripple.value) * press.clamp(0.0, 1.0);
+          final dragStretch = dragWave * (dragWave >= 0 ? 0.10 : 0.06);
           final speed = _reduceMotion
               ? 0.0
               : (_drag != null ? _dragSpeed : _motion.velocity).abs();
           final stretch =
-              (speed / 80).clamp(0.0, 0.08) + tapStretch + press * 0.30;
+              (speed / 80).clamp(0.0, 0.08) +
+              tapStretch +
+              press * 0.30 +
+              dragStretch;
           final lensWidth = _travel * (1 + stretch);
           final lensHeight =
               (_height - _inset * 2) *
-              (1 + press * 0.31 + tapRise - (speed / 180).clamp(0.0, 0.035));
+              (1 +
+                  press * 0.31 +
+                  tapRise -
+                  dragWave * 0.08 -
+                  (speed / 180).clamp(0.0, 0.035));
           // Resize real glass bounds: sampling stays aligned without scaling text.
           final sway = _reduceMotion ? 0.0 : _sway.value.clamp(-1.2, 1.2);
           final bodyGrowth = press * 12 + pulse * 3 + sway.abs() * 4;
           final bodyHeight =
               _height + press * 5 + pulse * 1.5 - sway.abs() * 0.8;
           final dockShift = sway * 8;
+          final leadingPull = sway * 6;
           return SizedBox(
             width: _width,
             height: _height,
@@ -245,9 +363,9 @@ class _GlassDockState extends State<GlassDock> with TickerProviderStateMixin {
                       boxShadow: [
                         BoxShadow(
                           color: const Color(0xFF4C6078)
-                              .withValues(alpha: 0.075),
+                              .withValues(alpha: 0.05),
-                          blurRadius: 18,
+                          blurRadius: 14,
-                          offset: const Offset(0, 6),
+                          offset: const Offset(0, 4),
                         ),
                       ],
                     ),
@@ -255,9 +373,9 @@ class _GlassDockState extends State<GlassDock> with TickerProviderStateMixin {
                       clipBehavior: Clip.none,
                       children: [
                         Positioned(
-                          left: -bodyGrowth / 2,
+                          left: -bodyGrowth / 2 + math.min(leadingPull, 0),
                           top: (_height - bodyHeight) / 2,
-                          width: _width + bodyGrowth,
+                          width: _width + bodyGrowth + leadingPull.abs(),
                           height: bodyHeight,
                           child: _glass(child: const SizedBox.expand()),
                         ),
@@ -328,7 +446,11 @@ class _GlassDockState extends State<GlassDock> with TickerProviderStateMixin {
             onHorizontalDragStart: index == widget.selectedIndex
                 ? (_) {
                     final start = _position.clamp(0.0, 2.0);
+                    _dragFollow.value = start;
+                    _dragTarget = start;
+                    _dragVelocity = _motion.velocity;
                     _motion.stop();
+                    _wakeRipple();
                     _pressTo(_reduceMotion ? 0 : 1);
                     setState(() {
                       _drag = start;
@@ -339,18 +461,20 @@ class _GlassDockState extends State<GlassDock> with TickerProviderStateMixin {
             onHorizontalDragUpdate: index == widget.selectedIndex
                 ? (details) => setState(() {
                     _dragSpeed = details.delta.dx / _travel * 60;
+                    _wakeRipple();
                     _swayTo((_dragSpeed / 8).clamp(-1.0, 1.0));
-                    _drag = (_position + details.delta.dx / _travel).clamp(
+                    _drag = (_drag! + details.delta.dx / _travel).clamp(
                       0.0,
                       2.0,
                     );
+                    _followDragTo(_drag!);
                   })
                 : null,
             onHorizontalDragEnd: index == widget.selectedIndex
                 ? (details) => _select(
-                    _position.round().clamp(0, 2),
+                    (_drag ?? _position).round().clamp(0, 2),
                     elastic: true,
-                    velocity: details.velocity.pixelsPerSecond.dx / _travel,
+                    velocity: _dragVelocity,
                   )
                 : null,
             onHorizontalDragCancel: index == widget.selectedIndex
@@ -359,7 +483,7 @@ class _GlassDockState extends State<GlassDock> with TickerProviderStateMixin {
                     final position = _position;
                     setState(() => _drag = null);
                     _motion.value = position;
-                    _moveTo(widget.selectedIndex);
+                    _moveTo(widget.selectedIndex, velocity: _dragVelocity);
                     _pressTo(0);
                     _swayTo(0);
                   }
@@ -515,7 +639,7 @@ class _GlassRimPainter extends CustomPainter {
       outer,
       Paint()
         ..style = PaintingStyle.stroke
-        ..strokeWidth = lens ? 1.8 : 2.8
+        ..strokeWidth = lens ? 1.4 : 1.8
         ..maskFilter = MaskFilter.blur(BlurStyle.normal, lens ? 0.9 : 0.65)
         ..shader = ui.Gradient.linear(
           bounds.topLeft,
@@ -532,7 +656,7 @@ class _GlassRimPainter extends CustomPainter {
       outer,
       Paint()
         ..style = PaintingStyle.stroke
-        ..strokeWidth = lens ? 1.25 : 1.1
+        ..strokeWidth = lens ? 1.0 : 0.85
         ..shader = ui.Gradient.sweep(
           bounds.center,
           [
@@ -553,7 +677,7 @@ class _GlassRimPainter extends CustomPainter {
       inner,
       Paint()
         ..style = PaintingStyle.stroke
-        ..strokeWidth = 0.7
+        ..strokeWidth = 0.45
         ..shader = ui.Gradient.linear(
           bounds.topLeft,
           bounds.bottomRight,

mobile/pubspec.yaml

@@ -1,7 +1,7 @@
 name: hepan_everyday
 description: TPSchedule 学生课表
 publish_to: none
-version: 0.7.8+30
+version: 0.7.8+31
 environment:
   sdk: ^3.13.5
 dependencies:

mobile/shaders/liquid_glass.frag

@@ -43,8 +43,8 @@ void main() {
   colour = mix(colour, reflected, min(edge_light * 0.18, 0.22));
   // A grazing-angle white reflection gives the curved rim visible thickness;
   // the broad centre continues to transmit the live, lightly softened scene.
-  colour.rgb = mix(colour.rgb, vec3(colour.a), min(edge_light * 0.20, 0.22));
+  colour.rgb = mix(colour.rgb, vec3(colour.a), min(edge_light * 0.15, 0.18));
-  float reflection = edge_light * 0.10;
+  float reflection = edge_light * 0.075;
   colour.rgb = min(colour.rgb + reflection * colour.a, vec3(colour.a));
   frag_color = colour;
 }

mobile/test/widgets/dock_motion_test.dart

@@ -11,6 +11,37 @@ import 'navigation_test.dart' show uiController;
 
 void main() {
   setUpAll(tzdata.initializeTimeZones);
+  testWidgets('drag tugs the leading edge and lens follows with elastic lag', (
+    tester,
+  ) async {
+    await tester.pumpWidget(_dock());
+    await tester.pumpAndSettle();
+    await tester.tap(find.byIcon(Icons.assignment_rounded));
+    await tester.pumpAndSettle();
+    final lens = find.byType(GlassRefraction).last;
+    final body = find.byType(GlassRefraction).first;
+    final gesture = await tester.startGesture(
+      tester.getCenter(find.byKey(const Key('dock-cursor'))),
+    );
+    await tester.pump(const Duration(milliseconds: 110));
+    await tester.pump(const Duration(milliseconds: 700));
+    await gesture.moveBy(const Offset(24, 0));
+    await tester.pump();
+    final initialX = tester.getCenter(lens).dx;
+    final initialBody = tester.getRect(body);
+    await gesture.moveBy(const Offset(60, 0));
+    await tester.pump();
+    expect(tester.getCenter(lens).dx - initialX, lessThan(45));
+    await tester.pump(const Duration(milliseconds: 180));
+    expect(tester.getCenter(lens).dx, greaterThan(initialX + 35));
+    final draggedBody = tester.getRect(body);
+    final leading = draggedBody.right - initialBody.right;
+    final trailing = draggedBody.left - initialBody.left;
+    expect(leading - trailing, greaterThan(7));
+    await gesture.cancel();
+    await tester.pumpAndSettle();
+    expect(tester.takeException(), isNull);
+  });
   testWidgets('inactive icon press leaves the cursor at its resting size', (
     tester,
   ) async {
@@ -80,6 +111,42 @@ void main() {
     await tester.pumpAndSettle();
     expect(tester.getSize(body), resting.size);
   });
+  testWidgets(
+    'lens keeps softly stretching and squeezing during an even drag',
+    (tester) async {
+      await tester.pumpWidget(_dock());
+      await tester.pumpAndSettle();
+      final lens = find.byType(GlassRefraction).last;
+      final gesture = await tester.startGesture(
+        tester.getCenter(find.byKey(const Key('dock-cursor'))),
+      );
+      await tester.pump(const Duration(milliseconds: 110));
+      await tester.pump(const Duration(milliseconds: 700));
+      await gesture.moveBy(const Offset(24, 0));
+      await tester.pump();
+      final widths = <double>[], heights = <double>[], centres = <double>[];
+      for (var i = 0; i < 22; i++) {
+        await gesture.moveBy(const Offset(5, 0));
+        await tester.pump(const Duration(milliseconds: 20));
+        if (i > 3) {
+          final size = tester.getSize(lens);
+          widths.add(size.width);
+          heights.add(size.height);
+          centres.add(tester.getCenter(lens).dx);
+        }
+      }
+      expect(widths.reduce(math.max) - widths.reduce(math.min), greaterThan(6));
+      expect(
+        heights.reduce(math.max) - heights.reduce(math.min),
+        greaterThan(2),
+      );
+      expect(centres.last - centres.first, greaterThan(50));
+      await gesture.up();
+      await tester.pumpAndSettle();
+      expect(tester.getSize(lens).width, closeTo(86, 0.1));
+      expect(tester.getSize(lens).height, closeTo(52, 0.1));
+    },
+  );
   testWidgets(
     'rapid reverse taps keep position continuous and finish on last tab',
     (tester) async {
@@ -258,7 +325,9 @@ void main() {
     await tester.pump();
     await gesture.moveBy(const Offset(86, 0));
     await tester.pump();
-    await tester.pump(const Duration(milliseconds: 180));
+    for (var frame = 0; frame < 12; frame++) {
+      await tester.pump(const Duration(milliseconds: 16));
+    }
     expect(tester.getCenter(icon).dy, lessThan(y - 1));
     await tester.pump(const Duration(milliseconds: 600));
     expect(tester.getCenter(icon).dy, closeTo(y, 0.1));
@@ -278,7 +347,9 @@ void main() {
     await tester.pump();
     await gesture.moveBy(const Offset(86, 0));
     await tester.pump();
-    await tester.pump(const Duration(milliseconds: 180));
+    for (var frame = 0; frame < 12; frame++) {
+      await tester.pump(const Duration(milliseconds: 16));
+    }
     final before = tester.getRect(icon);
     await gesture.up();
     await tester.pump();

mobile/test/widgets/glass_material_test.dart

@@ -23,8 +23,8 @@ void main() {
       // while its original cool colour remains visible through the material.
       final red = _channel(pixels, 160, 43, 0);
       final green = _channel(pixels, 160, 43, 1);
-      expect(red, greaterThan(75));
+      expect(red, greaterThan(50));
-      expect(red, lessThan(115));
+      expect(red, lessThan(80));
       expect(green - red, closeTo(13, 6));
     },
   );