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Created attachment 20953 [details]
git clone https://github.com/milan11/xamarin_forms_list_test
Nexus 6 with Android 7.0
Xamarin Forms 18.104.22.168
Open in debug mode from Visual Studio.
Do this repeatedly (fast):
- click "Go to list" button
- press back
(you should be able to reproduce it after doing this max. 20 times)
The app crashes (with the "App has stopped" dialog).
Logcat log: log_assertion
This is maybe interesting:
Abort message: '* Assertion at /Users/builder/data/lanes/4009/3a62f1ea/source/mono/mono/metadata/sgen-tarjan-bridge.c:1139, condition `xref_count == xref_index' not met'
In Visual Studio - Output:
F/ ( 1709): * Assertion at /Users/builder/data/lanes/4009/3a62f1ea/source/mono/mono/metadata/sgen-tarjan-bridge.c:1139, condition `xref_count == xref_index' not met
F/libc ( 1709): Fatal signal 6 (SIGABRT), code -6 in tid 1709 (App4.Android)
With Xamarin Forms 22.214.171.124-nightly or with another device (android-x86.org Android 7 build running on VMWare) I observed another behavior:
- app simply disappeared (no "App has stopped" dialog)
- no "Abort message" in the log: log_other
Some sort of crashes can be reproduced in Release builds, too.
I was able to get an emulator to crash though it took more than 20 attempts and I had alt-tabbed away from it for a moment as well. There's no explicit mention of Forms in those logs that I can see, so it may or may not be a Forms-specific issue, but I will leave it filed under this and confirmed for the time being until it's further investigated.
The assert is fired from the runtime. Typically, an assert indicates a bug in the component from which it was fired and not the client of the component. So let's ask the mono team if they believe this indicates a bug in their code or ours.
I am having the same issue while navigating the Detail Page from the Master Page.
I have a sample app here.
I'm having the same issue.
I'm using Xamarin 126.96.36.1994 for Visual Studio with Xamarin.Forms 188.8.131.52. I'm also using a ListView inside the DetailPage from a MasterPage, like the case above.
Chris King, what does "let's" mean?
Did you ask the mono team about it, or should some of us ask?
Btw started to have this as well at BQ Aquaris U running 6.0.1 when moved my listview itemsource to viewmodel and updating the list periodically via binding.
My ListView is in MasterDetail which has Navigation page as detail and on this page root I have a listview.
Only appears in debug mode.
Before I updated the list through events and was also setting listview.Itemsource to null before passing the real itemSource (as I had a bug where half-transparent cells are overlaying each other) and didn't have that.
I have the same issue with a non-Forms app.
I have a ListView that directs to another activity with various EditText.
If I go back and forth multiple times, it crashes.
I have more info on this. It might be linked to ReactiveUI.
I have opened an issue on their GitHub page : https://github.com/reactiveui/ReactiveUI/issues/1379
A sample project is included.
Any news about this bug? I have the same problem
I experienced the same issue until I added an Android environment file as described here and used the 'old' GC Bridge: