Conflict between SlidableAutoCloseBehavior and custom SlidableController

[cerenyasa]

The issue described #482 still persists.
When the list is wrapped with SlidableAutoCloseBehavior and a custom SlidableController is assigned to any item, triggering open() or close() programmatically results in the following error.

Previously, adding a const Key used to resolve the issue, but that no longer works.

Could you please take another look?

`The following assertion was thrown while notifying status listeners for AnimationController:
This widget has been unmounted, so the State no longer has a context (and should be considered defunct).

Consider canceling any active work during "dispose" or using the "mounted" getter to determine if the State is still active.
When the exception was thrown, this was the stack:
#0 State.context. (package:flutter/src/widgets/framework.dart:952:9)
#1 State.context (package:flutter/src/widgets/framework.dart:958:6)
#2 _SlidableAutoCloseBarrierNotificationSenderState._handleStatusChanged (package:flutter_slidable/src/auto_close_behavior.dart:361:9)
#3 _SlidableNotificationSenderState.handleStatusChanged (package:flutter_slidable/src/auto_close_behavior.dart:531:29)
#4 AnimationLocalStatusListenersMixin.notifyStatusListeners (package:flutter/src/animation/listener_helpers.dart:243:19)
#5 AnimationController._checkStatusChanged (package:flutter/src/animation/animation_controller.dart:945:7)
#6 AnimationController._startSimulation (package:flutter/src/animation/animation_controller.dart:878:5)
#7 AnimationController._animateToInternal (package:flutter/src/animation/animation_controller.dart:688:12)
#8 AnimationController.animateBack (package:flutter/src/animation/animation_controller.dart:637:12)
#9 SlidableController.close (package:flutter_slidable/src/controller.dart:264:32)
...
#13 GestureRecognizer.invokeCallback (package:flutter/src/gestures/recognizer.dart:345:24)
#14 TapGestureRecognizer.handleTapUp (package:flutter/src/gestures/tap.dart:737:11)
#15 BaseTapGestureRecognizer._checkUp (package:flutter/src/gestures/tap.dart:362:5)
#16 BaseTapGestureRecognizer.acceptGesture (package:flutter/src/gestures/tap.dart:332:7)
#17 GestureArenaManager.sweep (package:flutter/src/gestures/arena.dart:173:27)
#18 GestureBinding.handleEvent (package:flutter/src/gestures/binding.dart:534:20)
#19 GestureBinding.dispatchEvent (package:flutter/src/gestures/binding.dart:499:22)
#20 RendererBinding.dispatchEvent (package:flutter/src/rendering/binding.dart:473:11)
#21 GestureBinding._handlePointerEventImmediately (package:flutter/src/gestures/binding.dart:437:7)
#22 GestureBinding.handlePointerEvent (package:flutter/src/gestures/binding.dart:394:5)
#23 GestureBinding._flushPointerEventQueue (package:flutter/src/gestures/binding.dart:341:7)
#24 GestureBinding._handlePointerDataPacket (package:flutter/src/gestures/binding.dart:308:9)
#28 _invoke1 (dart:ui/hooks.dart:349:10)
#29 PlatformDispatcher._dispatchPointerDataPacket (dart:ui/platform_dispatcher.dart:467:7)
#30 _dispatchPointerDataPacket (dart:ui/hooks.dart:282:31)
(elided 3 frames from dart:async)
The AnimationController notifying status listeners was: AnimationController#736ba(◀ 0.350)
`

[FuugaMo]

I ran into the same problem just now.

[FuugaMo]

Hi, just wanted to share my workaround for this issue in case it helps someone.

I ran into the same error when using a custom SlidableController together with SlidableAutoCloseBehavior, especially in situations where animations were triggered programmatically (e.g. via .open() / .close()), and then the widget was later disposed.

In my case, I resolved it by managing the active controller manually and adding a mounted check inside the addStatusListener. Here’s the setup:

First, define:

final Map<int, SlidableController> _controllers = {};
SlidableController? _activeSlidableController;

Core logic:

final controller = _controllers.putIfAbsent(index, () {
  final newController = SlidableController(this);

  newController.animation.addStatusListener((status) {
    if (!mounted) return;

    if (status == AnimationStatus.forward) {
      final previous = _activeSlidableController;
      _activeSlidableController = newController;

      if (previous != null && previous != newController) {
        previous.close();
      }
    }

    if (status == AnimationStatus.dismissed &&
        _activeSlidableController == newController) {
      _activeSlidableController = null;
    }
  });

  return newController;
});

In Slidable:

return Slidable(
  controller: controller,
  closeOnScroll: true,
  key: ValueKey(_reminders[index]),
  endActionPane: ActionPane( 
    // ...
  ),
);

This way, I avoid relying on SlidableAutoCloseBehavior’s auto logic and prevent the AnimationController from trying to notify listeners after the widget has been unmounted.

⸻

However, in this manual setup — where I track the active SlidableController via animation.status to ensure only one Slidable is open at a time — I encountered a subtle issue:

When the user manually drags a Slidable all the way open, instead of flicking it quickly, the animation’s status can get stuck at AnimationStatus.reverse, even though the panel is visibly open.

As a result, the forward status is never triggered, and the logic that closes the previously open Slidable doesn’t execute — leaving multiple Slidables open.

This does not happen when the user opens a Slidable with a quick swipe; in that case, the animation proceeds through forward → completed as expected.

Has anyone else encountered this and found a reliable workaround?