Prevent modal sheet from poping while dragging (#62)

This PR fixes #54.

A modal sheet can now be dismissed by clicking the barrier ONLY when its
status is `SheetStatus.stable` and the pull-to-dismiss action is not
running.

package/CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## 0.3.4 Mar 9, 2024
+
+- Fix crash when clicking on the modal barrier while dragging the sheet (#54)
+
 ## 0.3.3 Feb 29, 2024
 
 - Add `InterpolationSimulation` (#55)

package/lib/src/foundation/sheet_activity.dart

@@ -5,6 +5,7 @@ import 'package:flutter/scheduler.dart';
 import 'package:flutter/widgets.dart';
 import 'package:smooth_sheets/src/foundation/notification.dart';
 import 'package:smooth_sheets/src/foundation/sheet_extent.dart';
+import 'package:smooth_sheets/src/foundation/sheet_status.dart';
 
 abstract class SheetActivity extends ChangeNotifier {
   bool _mounted = false;
@@ -24,6 +25,8 @@ abstract class SheetActivity extends ChangeNotifier {
 
   double get velocity => 0.0;
 
+  SheetStatus get status;
+
   @mustCallSuper
   void initWith(SheetExtent delegate) {
     assert(
@@ -147,7 +150,7 @@ abstract class SheetActivity extends ChangeNotifier {
 }
 
 class AnimatedSheetActivity extends SheetActivity
-    with DrivenSheetActivityMixin {
+    with ControlledSheetActivityMixin {
   AnimatedSheetActivity({
     required this.from,
     required this.to,
@@ -178,7 +181,7 @@ class AnimatedSheetActivity extends SheetActivity
 }
 
 class BallisticSheetActivity extends SheetActivity
-    with DrivenSheetActivityMixin {
+    with ControlledSheetActivityMixin {
   BallisticSheetActivity({
     required this.simulation,
   });
@@ -201,9 +204,12 @@ class BallisticSheetActivity extends SheetActivity
   }
 }
 
-class IdleSheetActivity extends SheetActivity {}
+class IdleSheetActivity extends SheetActivity {
+  @override
+  SheetStatus get status => SheetStatus.stable;
+}
 
-mixin DrivenSheetActivityMixin on SheetActivity {
+mixin ControlledSheetActivityMixin on SheetActivity {
   late final AnimationController controller;
   late double _lastAnimatedValue;
 
@@ -217,6 +223,9 @@ mixin DrivenSheetActivityMixin on SheetActivity {
   @override
   double get velocity => controller.velocity;
 
+  @override
+  SheetStatus get status => SheetStatus.controlled;
+
   @override
   void initWith(SheetExtent delegate) {
     super.initWith(delegate);
@@ -246,6 +255,9 @@ mixin DrivenSheetActivityMixin on SheetActivity {
 }
 
 mixin UserControlledSheetActivityMixin on SheetActivity {
+  @override
+  SheetStatus get status => SheetStatus.userControlled;
+
   @override
   void didFinalizeDimensions(
     Size? oldContentDimensions,

package/lib/src/foundation/sheet_extent.dart

@@ -1,11 +1,7 @@
 import 'package:flutter/widgets.dart';
-import 'package:smooth_sheets/src/draggable/draggable_sheet.dart';
-import 'package:smooth_sheets/src/foundation/sheet_activity.dart';
-import 'package:smooth_sheets/src/foundation/sheet_controller.dart';
-import 'package:smooth_sheets/src/foundation/sheet_physics.dart';
+import 'package:smooth_sheets/smooth_sheets.dart';
+import 'package:smooth_sheets/src/foundation/sheet_status.dart';
 import 'package:smooth_sheets/src/internal/double_utils.dart';
-import 'package:smooth_sheets/src/scrollable/scrollable_sheet.dart';
-import 'package:smooth_sheets/src/scrollable/scrollable_sheet_extent.dart';
 
 /// A representation of a visible height of the sheet.
 ///
@@ -162,6 +158,9 @@ abstract class SheetExtent with ChangeNotifier, MaybeSheetMetrics {
     return SheetMetricsSnapshot.from(metrics);
   }
 
+  @override
+  SheetStatus get status => _activity!.status;
+
   @override
   double? get pixels => _activity!.pixels;
 
@@ -398,6 +397,9 @@ class ViewportDimensions {
 
 /// A description of the state of a sheet.
 mixin MaybeSheetMetrics {
+  /// The current status of the sheet.
+  SheetStatus get status;
+
   /// The current extent of the sheet.
   double? get pixels;
 
@@ -502,6 +504,7 @@ mixin SheetMetrics on MaybeSheetMetrics {
 class SheetMetricsSnapshot with MaybeSheetMetrics, SheetMetrics {
   /// Creates an immutable description of the sheet's state.
   const SheetMetricsSnapshot({
+    required this.status,
     required this.pixels,
     required this.minPixels,
     required this.maxPixels,
@@ -512,6 +515,7 @@ class SheetMetricsSnapshot with MaybeSheetMetrics, SheetMetrics {
   /// Creates a snapshot of the given [SheetMetrics].
   factory SheetMetricsSnapshot.from(SheetMetrics other) {
     return SheetMetricsSnapshot(
+      status: other.status,
       pixels: other.pixels,
       minPixels: other.minPixels,
       maxPixels: other.maxPixels,
@@ -520,6 +524,9 @@ class SheetMetricsSnapshot with MaybeSheetMetrics, SheetMetrics {
     );
   }
 
+  @override
+  final SheetStatus status;
+
   @override
   final double pixels;
 
@@ -539,14 +546,17 @@ class SheetMetricsSnapshot with MaybeSheetMetrics, SheetMetrics {
   bool get hasPixels => true;
 
   /// Creates a copy of this object with the given fields replaced.
+
   SheetMetricsSnapshot copyWith({
+    SheetStatus? status,
     double? pixels,
     double? minPixels,
     double? maxPixels,
     Size? contentDimensions,
     ViewportDimensions? viewportDimensions,
   }) {
     return SheetMetricsSnapshot(
+      status: status ?? this.status,
       pixels: pixels ?? this.pixels,
       minPixels: minPixels ?? this.minPixels,
       maxPixels: maxPixels ?? this.maxPixels,
@@ -593,6 +603,9 @@ class _SheetMetricsRef with MaybeSheetMetrics, SheetMetrics {
 
   final MaybeSheetMetrics _source;
 
+  @override
+  SheetStatus get status => _source.status;
+
   @override
   double get pixels => _source.pixels!;
 

package/lib/src/foundation/sheet_status.dart

@@ -0,0 +1,11 @@
+/// The status of a sheet.
+enum SheetStatus {
+  /// The sheet is resting at a natural position.
+  stable,
+
+  /// The sheet position is controlled by a programmatic way such as animation.
+  controlled,
+
+  /// The sheet position is controlled by a user gesture such as dragging.
+  userControlled,
+}

package/lib/src/modal/modal_sheet.dart

@@ -4,6 +4,7 @@ import 'dart:ui';
 
 import 'package:flutter/material.dart';
 import 'package:smooth_sheets/src/foundation/sheet_controller.dart';
+import 'package:smooth_sheets/src/foundation/sheet_status.dart';
 import 'package:smooth_sheets/src/internal/double_utils.dart';
 import 'package:smooth_sheets/src/internal/monodrag.dart';
 
@@ -185,6 +186,40 @@ mixin ModalSheetRouteMixin<T> on ModalRoute<T> {
       child: child,
     );
   }
+
+  @override
+  Widget buildModalBarrier() {
+    void onDismiss() {
+      if (animation!.status == AnimationStatus.completed &&
+          sheetController.metrics?.status == SheetStatus.stable) {
+        navigator?.maybePop();
+      }
+    }
+
+    final barrierColor = this.barrierColor;
+    if (barrierColor != null && barrierColor.alpha != 0 && !offstage) {
+      assert(barrierColor != barrierColor.withOpacity(0.0));
+      return AnimatedModalBarrier(
+        onDismiss: onDismiss,
+        dismissible: barrierDismissible,
+        semanticsLabel: barrierLabel,
+        barrierSemanticsDismissible: semanticsDismissible,
+        color: animation!.drive(
+          ColorTween(
+            begin: barrierColor.withOpacity(0.0),
+            end: barrierColor,
+          ).chain(CurveTween(curve: barrierCurve)),
+        ),
+      );
+    } else {
+      return ModalBarrier(
+        onDismiss: onDismiss,
+        dismissible: barrierDismissible,
+        semanticsLabel: barrierLabel,
+        barrierSemanticsDismissible: semanticsDismissible,
+      );
+    }
+  }
 }
 
 class SheetDismissible extends StatefulWidget {
@@ -231,7 +266,7 @@ class _SheetDismissibleState extends State<SheetDismissible> {
     super.didChangeDependencies();
     _gestureRecognizer.gestureSettings =
         MediaQuery.maybeGestureSettingsOf(context);
-    _sheetController = DefaultSheetController.of(context);
+    _sheetController = SheetControllerScope.of(context);
 
     assert(
       ModalRoute.of(context) is ModalSheetRouteMixin<dynamic>,

package/lib/src/navigation/navigation_route.dart

@@ -2,6 +2,7 @@ import 'package:flutter/material.dart';
 import 'package:smooth_sheets/src/foundation/framework.dart';
 import 'package:smooth_sheets/src/foundation/sheet_activity.dart';
 import 'package:smooth_sheets/src/foundation/sheet_extent.dart';
+import 'package:smooth_sheets/src/foundation/sheet_status.dart';
 import 'package:smooth_sheets/src/navigation/navigation_sheet.dart';
 
 mixin NavigationSheetRouteMixin<T> on NavigationSheetRoute<T> {
@@ -109,6 +110,9 @@ class _SheetExtentBox extends ChangeNotifier
     super.dispose();
   }
 
+  @override
+  SheetStatus get status => _source?.status ?? SheetStatus.stable;
+
   @override
   double? get pixels => _source?.pixels;
 

package/lib/src/navigation/navigation_sheet.dart

@@ -8,6 +8,7 @@ import 'package:smooth_sheets/src/foundation/sheet_activity.dart';
 import 'package:smooth_sheets/src/foundation/sheet_controller.dart';
 import 'package:smooth_sheets/src/foundation/sheet_extent.dart';
 import 'package:smooth_sheets/src/foundation/sheet_physics.dart';
+import 'package:smooth_sheets/src/foundation/sheet_status.dart';
 import 'package:smooth_sheets/src/internal/transition_observer.dart';
 
 typedef NavigationSheetTransitionObserver = TransitionObserver;
@@ -128,6 +129,7 @@ abstract class NavigationSheetExtentDelegate implements Listenable {
   double? get pixels;
   double? get minPixels;
   double? get maxPixels;
+  SheetStatus get status;
   void applyNewViewportDimensions(ViewportDimensions viewportDimensions);
   void beginActivity(SheetActivity activity);
 }
@@ -237,6 +239,9 @@ class _TransitionSheetActivity extends SheetActivity {
 
   late final Animation<double> _curvedAnimation;
 
+  @override
+  SheetStatus get status => SheetStatus.controlled;
+
   @override
   void initWith(SheetExtent target) {
     super.initWith(target);
@@ -268,6 +273,9 @@ class _ProxySheetActivity extends SheetActivity {
 
   final NavigationSheetExtentDelegate target;
 
+  @override
+  SheetStatus get status => target.status;
+
   @override
   double? get pixels {
     if (target.pixels != null) {

package/lib/src/scrollable/scrollable_sheet_extent.dart

@@ -4,6 +4,7 @@ import 'package:flutter/material.dart';
 import 'package:smooth_sheets/src/foundation/sheet_activity.dart';
 import 'package:smooth_sheets/src/foundation/sheet_extent.dart';
 import 'package:smooth_sheets/src/foundation/sheet_physics.dart';
+import 'package:smooth_sheets/src/foundation/sheet_status.dart';
 import 'package:smooth_sheets/src/foundation/sized_content_sheet.dart';
 import 'package:smooth_sheets/src/internal/double_utils.dart';
 import 'package:smooth_sheets/src/internal/into.dart';
@@ -242,6 +243,9 @@ class _ContentIdleScrollDrivenSheetActivity
 
   final Extent initialExtent;
 
+  @override
+  SheetStatus get status => SheetStatus.stable;
+
   @override
   void didChangeContentDimensions(Size? oldDimensions) {
     super.didChangeContentDimensions(oldDimensions);
@@ -288,6 +292,9 @@ class _ContentUserScrollDrivenSheetActivity
 
 class _ContentBallisticScrollDrivenSheetActivity
     extends _ContentScrollDrivenSheetActivity {
+  @override
+  SheetStatus get status => SheetStatus.controlled;
+
   @override
   DelegationResult<double> applyBallisticScrollOffset(
     double delta,

package/pubspec.yaml

@@ -1,6 +1,6 @@
 name: smooth_sheets
 description: Sheet widgets with smooth motion and great flexibility. Also supports nested navigation in both imperative and declarative ways.
-version: 0.3.3
+version: 0.3.4
 repository: https://github.com/fujidaiti/smooth_sheets
 
 environment:

package/test/foundation/sheet_physics_test.dart

@@ -1,12 +1,14 @@
 import 'package:flutter/widgets.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:smooth_sheets/smooth_sheets.dart';
+import 'package:smooth_sheets/src/foundation/sheet_status.dart';
 
 class _SheetPhysicsWithDefaultConfiguration extends SheetPhysics {
   const _SheetPhysicsWithDefaultConfiguration();
 }
 
 const _referenceSheetMetrics = SheetMetricsSnapshot(
+  status: SheetStatus.stable,
   minPixels: 0,
   maxPixels: 600,
   pixels: 600,