Bug 28191 - Java.Lang.NullPointerException in TabbedPage
Summary: Java.Lang.NullPointerException in TabbedPage
Status: VERIFIED FIXED
Alias: None
Product: Forms
Classification: Xamarin
Component: Forms ()
Version: 1.4.0
Hardware: PC Windows
: Normal normal
Target Milestone: ---
Assignee: Bugzilla
URL:
Depends on:
Blocks:
 
Reported: 2015-03-19 08:02 UTC by R.Schindler
Modified: 2015-04-23 11:33 UTC (History)
5 users (show)

Tags:
Is this bug a regression?: ---
Last known good build:


Attachments
Example Project for exception (4.57 MB, application/x-zip-compressed)
2015-03-19 08:02 UTC, R.Schindler
Details
Zip Xamarin Logs (393.83 KB, application/octet-stream)
2015-03-19 12:25 UTC, Udham Singh
Details


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Related Links:
Status:
VERIFIED FIXED

Description R.Schindler 2015-03-19 08:02:08 UTC
Created attachment 10408 [details]
Example Project for exception

Hi,
I'm getting an Error in Xamarin.Forms 1.4.0 when I PopModalAsync to a TabbedPage and try to Update the values on the DetailPage of the TabbedPage. This is only happening on Android. On iOS it works.

This is how you can reproduce the error in the example app.

Start the app ->
Click on an item in the master ->
Click on the ToolbarItem "Press me" ->
Click on the ToolbarItem "Close me" ->
Get exception :)

System Information.

Microsoft Visual Studio Professional 2012
Version 11.0.61030.00 Update 4
Microsoft .NET Framework
Version 4.5.50938

Installierte Version: Professional

LightSwitch für Visual Studio 2012   04938-004-0033001-02812
Microsoft LightSwitch für Visual Studio 2012

Office Developer Tools   04938-004-0033001-02812
Microsoft Office Developer Tools

Rechtschreibprüfung für die Visual Studio 2012-Codeanalyse   04938-004-0033001-02812
Rechtschreibprüfung für die Microsoft® Visual Studio® 2012-Codeanalyse

Teile des International CorrectSpell™-Rechtschreibprüfungssystems © 1993 by Lernout & Hauspie Speech Products N.V. Alle Rechte vorbehalten.

The American Heritage® Dictionary of the English Language, Third Edition Copyright © 1992 Houghton Mifflin Company. Elektronische Version lizenziert von Lernout & Hauspie Speech Products N.V. Alle Rechte vorbehalten.

Team Explorer für Visual Studio 2012   04938-004-0033001-02812
Microsoft Team Explorer für Visual Studio 2012

Visual Basic 2012   04938-004-0033001-02812
Microsoft Visual Basic 2012

Visual C# 2012   04938-004-0033001-02812
Microsoft Visual C# 2012

Visual C++ 2012   04938-004-0033001-02812
Microsoft Visual C++ 2012

Visual F# 2012   04938-004-0033001-02812
Microsoft Visual F# 2012

Visual Studio 2012 SharePoint Developer Tools   04938-004-0033001-02812
Microsoft Visual Studio 2012 SharePoint Developer Tools

ASP.NET and Web Tools   2012.3.41009
Microsoft Web Developer Tools contains the following components:
Support for creating and opening ASP.NET web projects
Browser Link: A communication channel between Visual Studio and browsers
Editor extensions for HTML, CSS, and JavaScript
Page Inspector: Inspection tool for ASP.NET web projects
Scaffolding: A framework for building and running code generators
Server Explorer extensions for Windows Azure Web Sites
Web publishing: Extensions for publishing ASP.NET web projects to hosting providers, on-premises servers, or Windows Azure

CodeMaid   #114
CodeMaid is an open source Visual Studio extension to cleanup, dig through and simplify our C#, C++, F#, VB, PHP, JSON, XAML, XML, ASP, HTML, CSS, LESS, SCSS, JavaScript and TypeScript coding.

Written by Steve Cadwallader, for more information visit http://www.codemaid.net/

JetBrains ReSharper Platform 6   Build 6.0.20141219.120158 on 2014-12-19 12:56:02Z
JetBrains ReSharper Platform package for Microsoft Visual Studio. For more information about ReSharper Platform, visit http://www.jetbrains.com/resharper. Copyright © 2015 JetBrains, Inc.

Microsoft Practices Project Linker   1.0
Microsoft patterns & practices project linker

NuGet-Paket-Manager   2.8.50926.602
NuGet-Paket-Manager in Visual Studio. Weitere Informationen zu NuGet finden Sie unter "http://docs.nuget.org/".

PreEmptive Analytics Visualizer   1.0
Microsoft Visual Studio-Erweiterung zur Visualisierung aggregierter Zusammenfassungen vom PreEmptive Analytics-Produkt.

SQL Server Data Tools   11.1.20828.01
Microsoft SQL Server Data Tools

StyleCop   4.7.49.0
Provides source code style and consistency tools. See http://www.stylecop.codeplex.com/ for more details.

Web Essentials   3.8
Adds many useful features to Visual Studio for web developers.

Xamarin   3.9.483.0 (978be3d)
Visual Studio extension to enable development for Xamarin.iOS and Xamarin.Android.

Xamarin.Android   4.20.0.37 (9e05e39f02bafe8fc0b7ab025d99f3b446835ad4)
Visual Studio plugin to enable development for Xamarin.Android.

Xamarin.iOS   8.8.0.0 (702be5207a1446b066f4653f68739da13c045227)
Visual Studio extension to enable development for Xamarin.iOS.

Xamarin.iOS Unified Migration   1.0
Automated migration for Xamarin iOS Classic projects to Unified
Comment 1 Udham Singh 2015-03-19 12:25:26 UTC
Created attachment 10414 [details]
Zip Xamarin Logs

I have checked this issue with the help of sample app and steps given in bug description and able to reproduce the reported behaviour. Please refer the screencast: http://www.screencast.com/t/e4JmLTlOL6aX

Adb Logcat : https://gist.github.com/Udham1/b17c6cb0f3e7360af4e3
Output Log : https://gist.github.com/Udham1/cb1647401f292baee2ef

Environment Info : 

Xamarin.Forms.1.4.1.6347-pre2

Microsoft Visual Studio Professional 2013
Version 12.0.31101.00 Update 4
Microsoft .NET Framework
Version 4.5.50938

Xamarin   3.9.523.0
Comment 2 Jason Smith [MSFT] 2015-04-08 16:34:56 UTC
Should be fixed in 1.4.2-pre1
Comment 3 R.Schindler 2015-04-09 02:04:04 UTC
Updated the test project to Xamarin.Forms 1.4.2-pre2 and the error still exists.

But I get a new exception:

An unhandled exception occured.
04-09 08:02:56.575 E/mono    ( 8809): Unable to find seq points for method '(wrapper managed-to-native) System.Diagnostics.Debugger:Mono_UnhandledException_internal (System.Exception)'.
04-09 08:02:56.575 F/        ( 8809): * Assertion at /Users/builder/data/lanes/1353/86274adf/source/mono/mono/mini/debugger-agent.c:5466, condition `sp' not met
04-09 08:02:56.577 E/mono-rt ( 8809): Stacktrace:
04-09 08:02:56.577 E/mono-rt ( 8809): 
04-09 08:02:56.578 E/mono-rt ( 8809): 
04-09 08:02:56.578 E/mono-rt ( 8809): =================================================================
04-09 08:02:56.578 E/mono-rt ( 8809): Got a SIGSEGV while executing native code. This usually indicates
04-09 08:02:56.578 E/mono-rt ( 8809): a fatal error in the mono runtime or one of the native libraries 
04-09 08:02:56.578 E/mono-rt ( 8809): used by your application.
04-09 08:02:56.578 E/mono-rt ( 8809): =================================================================
04-09 08:02:56.578 E/mono-rt ( 8809): 
04-09 08:02:56.580 F/libc    ( 8809): Fatal signal 11 (SIGSEGV) at 0xdeadbaad (code=1), thread 8855 (XFTest.Droid)
Step request failed: Eine Ausnahme vom Typ "Mono.Debugger.Soft.VMDisconnectedException" wurde ausgelöst.
Comment 4 R.Schindler 2015-04-22 05:09:14 UTC
This has been fixed in Xamarin.Forms 1.4.3-pre1. Thank you :)
Comment 5 Parmendra Kumar 2015-04-23 11:33:08 UTC
I have checked this issue with Xamarin.Forms 1.4.3-pre1 and its working fine at my end.

Hence closing this issue.

environment info:

Microsoft Visual Studio Professional 2013
Version 12.0.31101.00 Update 4
Microsoft .NET Framework
Version 4.5.51641

Installed Version: Professional

Xamarin   3.11.448.0 (e8d1103)
Visual Studio extension to enable development for Xamarin.iOS and Xamarin.Android.

Xamarin.Android   5.1.0.115 (d23da369e436488f38c8ab8fe8a9ae7d9ea5256b)
Visual Studio plugin to enable development for Xamarin.Android.

Xamarin.Forms Intellisense   1.0
Provides intellisense for Xamarin.Forms in the XML editor.

Xamarin.iOS   8.10.0.0 (7741cc495ab0baf04ff0405d0604bc27f0ecae2e)
Visual Studio extension to enable development for Xamarin.iOS.

Xamarin.iOS Unified Migration   1.0
Automated migration for Xamarin iOS Classic projects to Unified

Xamarin.TestCloud.Integration   1.0
Early preview of Xamarin Test Cloud integration