xamarin/Xamarin.Forms

[Bug] UWP app crash when starting in airplane mode with a map control

Open

#5,929 opened on Apr 16, 2019

View on GitHub
 (3 comments) (0 reactions) (0 assignees)C# (5,644 stars) (1,926 forks)batch import
a/maps :globe_with_meridians:e/2 :clock2:good first issuehelp wantedi/highinactivep/UWPt/bug :bug:up-for-grabs

Description

Description

A UWP app started in airplane mode crashes if a map control is present.

Steps to Reproduce

  1. Find a UWP project having a map control with IsShowingUser="True"
  2. Build it and run it while online. See that it works.
  3. Turn airplane mode on and run it again. See that it crashes.

Expected Behavior

No crash

Actual Behavior

Crash with unhandled exception in the UWP map renderer: EXCEPTION:

System.Exception : Exception from HRESULT: 0x80072EE7   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Xamarin.Forms.Maps.UWP.MapRenderer.<UpdateIsShowingUser>d__11.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Xamarin.Forms.Maps.UWP.MapRenderer.<OnElementChanged>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.AsyncMethodBuilderCore.<>c.<ThrowAsync>b__6_0(Object state)
   at System.Threading.WinRTSynchronizationContextBase.Invoker.InvokeCore()

Basic Information

  • Version with issue: Exists in 3.6.0.293080
  • Last known good version: Not sure
  • IDE: Visual Studio
  • Platform Target Frameworks:
    • UWP: 16299

Reproduction Link

https://github.com/xamarin/xamarin-forms-samples/tree/master/WorkingWithMaps

The HRESULT error code is explained here, having to do with server name resolution: https://ru.stackoverflow.com/a/915097

Contributor guide

Tech stack
csharp
Domain
mobile
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
C#UWP developmentbasic exception handling
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
70
Research direction
The crash occurs in Xamarin.Forms.Maps.UWP.MapRenderer.UpdateIsShowingUser method at line referenced in stack trace. The root cause is an unhandled exception from HRESULT: 0x80072EE7 (server name resolution failure) when network is unavailable. To fix, catch the exception in that method and handle gracefully (e.g., log and continue). Look at the GitHub repo for similar patterns in other renderers. The reproduction sample is linked. No existing PR, so implement a try catch around the code that calls the map service for user location.
[Bug] UWP app crash when starting in airplane mode with a map control · xamarin/Xamarin.Forms#5929 | Good First Issue