Fixed Dismissible animation issue

Author: letsar

CHANGELOG.md

@@ -1,3 +1,7 @@
+## 1.0.0-dev.8
+### Fixed
+* Fixes an issue where the Dismissible animation stopped in middle when the gesture was too fast.
+
 ## 1.0.0-dev.7
 ### Fixed
 * Fixes an issue where the Slidable animation stopped in middle when the gesture was too fast.

example/pubspec.lock

@@ -68,7 +68,7 @@ packages:
       path: ".."
       relative: true
     source: path
-    version: "1.0.0-dev.7"
+    version: "1.0.0-dev.8"
   flutter_test:
     dependency: "direct dev"
     description: flutter

lib/src/action_pane.dart

@@ -106,7 +106,7 @@ class _ActionPaneState extends State<ActionPane> implements RatioConfigurator {
   SlidableController? controller;
   late double openThreshold;
   late double closeThreshold;
-  bool? showMotion;
+  bool showMotion = true;
 
   @override
   double get extentRatio => widget.extentRatio;
@@ -120,7 +120,6 @@ class _ActionPaneState extends State<ActionPane> implements RatioConfigurator {
     if (widget.dismissible != null) {
       controller!.animation.addListener(handleRatioChanged);
     }
-    showMotion = true;
     updateThresholds();
     controller!.actionPaneConfigurator = this;
   }
@@ -173,7 +172,13 @@ class _ActionPaneState extends State<ActionPane> implements RatioConfigurator {
     final position = controller!.animation.value;
 
     if (widget.dismissible != null && position > widget.extentRatio) {
-      controller!.dismissGesture.value = DismissGesture(gesture);
+      if (controller!.isDismissibleReady) {
+        controller!.dismissGesture.value = DismissGesture(gesture);
+      } else {
+        // If the dismissible is not ready, the animation will stop.
+        // So we prefere to open the action pane instead.
+        controller!.openCurrentActionPane();
+      }
       return;
     }
 
@@ -190,7 +195,8 @@ class _ActionPaneState extends State<ActionPane> implements RatioConfigurator {
   }
 
   void handleRatioChanged() {
-    final show = controller!.ratio.abs() <= widget.extentRatio;
+    final show = controller!.ratio.abs() <= widget.extentRatio &&
+        !controller!.isDismissibleReady;
     if (show != showMotion) {
       setState(() {
         showMotion = show;
@@ -204,7 +210,7 @@ class _ActionPaneState extends State<ActionPane> implements RatioConfigurator {
 
     Widget? child;
 
-    if (showMotion!) {
+    if (showMotion) {
       final factor = widget.extentRatio;
       child = FractionallySizedBox(
         alignment: config.alignment,

lib/src/controller.dart

@@ -102,13 +102,14 @@ class SlidableController {
   SlidableController(TickerProvider vsync)
       : _animationController = AnimationController(vsync: vsync),
         endGesture = ValueNotifier(null),
-        dismissGesture = ValueNotifier(null),
+        _dismissGesture = _ValueNotifier(null),
         resizeRequest = ValueNotifier(null),
         actionPaneType = ValueNotifier(ActionPaneType.none) {
     _animationController.addListener(_onRatioChanged);
   }
 
   final AnimationController _animationController;
+  final _ValueNotifier<DismissGesture?> _dismissGesture;
 
   /// Whether the start action pane is enabled.
   bool enableStartActionPane = true;
@@ -156,14 +157,17 @@ class SlidableController {
   final ValueNotifier<EndGesture?> endGesture;
 
   /// Track the dismiss gestures.
-  final ValueNotifier<DismissGesture?> dismissGesture;
+  ValueNotifier<DismissGesture?> get dismissGesture => _dismissGesture;
 
   /// Track the resize requests.
   final ValueNotifier<ResizeRequest?> resizeRequest;
 
   /// Track the type of the action pane.
   final ValueNotifier<ActionPaneType> actionPaneType;
 
+  /// Indicates whether the dismissible registered to gestures.
+  bool get isDismissibleReady => _dismissGesture._hasListeners;
+
   /// Whether this [close()] method has been called and not finished.
   bool get closing => _closing;
   bool _closing = false;
@@ -323,6 +327,12 @@ class SlidableController {
   }
 }
 
+class _ValueNotifier<T> extends ValueNotifier<T> {
+  _ValueNotifier(T value) : super(value);
+
+  bool get _hasListeners => hasListeners;
+}
+
 /// Extensions for [ActionPaneType].
 extension ActionPaneTypeX on ActionPaneType {
   /// Transforms this [ActionPaneType] to a sign.

pubspec.yaml

@@ -1,6 +1,6 @@
 name: flutter_slidable
 description: A Flutter implementation of slidable list item with directional slide actions that can be dismissed.
-version: 1.0.0-dev.7
+version: 1.0.0-dev.8
 homepage: https://github.com/letsar/flutter_slidable
 
 environment: