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Cannot access a disposed object

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
android, csharp
Domain
mobile-dev

Research direction

Start by inspecting NotificationBuilder.TimerFinished and the Notify timer callback shown in the stack trace. Reproduce the failure on the reported Android environment if possible, then verify that the notification cancellation path no longer accesses a disposed Android.App.NotificationManager.

Written by the indexing model from the issue text.

Description

This is on a Xamarin Forms app.
Android: 9
Android Build: PKQ1.190118.001
Manufacturer: vivo
Model: vivo 1727

Xamarin Exception Stack:
System.ObjectDisposedException: Cannot access a disposed object.
Object name: 'Android.App.NotificationManager'.
  at Java.Interop.JniPeerMembers.AssertSelf (Java.Interop.IJavaPeerable self) [0x00029] in <4d2af34ca2694c37a4ea3d8074f2f66b>:0
  at Java.Interop.JniPeerMembers+JniInstanceMethods.InvokeVirtualVoidMethod (System.String encodedMember, Java.Interop.IJavaPeerable self, Java.Interop.JniArgumentValue* parameters) [0x00000] in <4d2af34ca2694c37a4ea3d8074f2f66b>:0
  at Android.App.NotificationManager.Cancel (System.Int32 id) [0x00022] in <519a5f3aaae444f4b50cf623ff03eb78>:0
  at Plugin.Toasts.NotificationBuilder.TimerFinished (System.String id, System.Boolean cancel, System.Boolean allowTapInNotificationCenter) [0x00028] in <ff2bac5dfa8f470a8c69cfd33f67eef9>:0
  at Plugin.Toasts.NotificationBuilder+<>c__DisplayClass23_1.<Notify>b__0 (System.Object x) [0x00031] in <ff2bac5dfa8f470a8c69cfd33f67eef9>:0
  at System.Threading.Timer+Scheduler.TimerCB (System.Object o) [0x00007] in <254b242c97154351aae8e0970082105e>:0
  at System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem () [0x00008] in <254b242c97154351aae8e0970082105e>:0
  at System.Threading.ThreadPoolWorkQueue.Dispatch () [0x00074] in <254b242c97154351aae8e0970082105e>:0
  at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback () [0x00000] in <254b242c97154351aae8e0970082105e>:0
Dominant language
C#
Stars
275
Forks
81
No merged PRs in 30d

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