Xamarin.Forms.Shel Loses Styling When Navigating to Home Page

[PatrickRyder]

Description

Create a Shell navigation structure like the one in the attached solution, comprising two main screens navigable by TabBar, then one 'child' non-modal, screen, leading to one modal 'child' screen.

Steps to Reproduce

1. From Home navigate to ChildScreenOne (non-modal).
2. From ChildScreenOne navigate to ChildScreenTwo (modal).
3. From ChildScreenTwo navigate back home using Shell.Current.GotoAsync( @"\Home" ).

Expected Behaviour

Navigation should occur and Shell should retain any styling that was applied to it.

Actual Behaviour

Navigation occurs but Shell loses styling.

Note that this doesn't happen if ChildScreenTwo is changed to be a non-modal screen.

Basic Information

• Version with issue: V16.11

• Last known good version: N/A because I have only recently begun using Shell.

• Platform Target Frameworks: Xamarin.iOS

  • iOS: 14.1

• NuGet Packages:
  Xamarin.iOS
  Xamarin.Forms
  Xamarin.CommunityToolkitMarkupExtensions
  Xamarin.Essentials

• Affected Devices:
  iOS simulator and physical device

Environment

Microsoft Visual Studio Community 2019
Version 16.11.0
VisualStudio.16.Release/16.11.0+31605.320
Microsoft .NET Framework
Version 4.8.04084

Installed Version: Community

.NET Core Debugging with WSL 1.0
.NET Core Debugging with WSL

ASP.NET and Web Tools 2019 16.11.75.64347
ASP.NET and Web Tools 2019

ASP.NET Web Frameworks and Tools 2012 16.11.75.64347
For additional information, visit https://www.asp.net/

ASP.NET Web Frameworks and Tools 2019 16.11.75.64347
For additional information, visit https://www.asp.net/

Azure App Service Tools v3.0.0 16.11.75.64347
Azure App Service Tools v3.0.0

Azure Functions and Web Jobs Tools 16.11.75.64347
Azure Functions and Web Jobs Tools

C# Tools 3.11.0-4.21403.6+ae1fff344d46976624e68ae17164e0607ab68b10
C# components used in the IDE. Depending on your project type and settings, a different version of the compiler may be used.

Common Azure Tools 1.10
Provides common services for use by Azure Mobile Services and Microsoft Azure Tools.

Extensibility Message Bus 1.2.6 (master@34d6af2)
Provides common messaging-based MEF services for loosely coupled Visual Studio extension components communication and integration.

IntelliCode Extension 1.0
IntelliCode Visual Studio Extension Detailed Info

Microsoft Azure Tools for Visual Studio 2.9
Support for Azure Cloud Services projects

Microsoft Continuous Delivery Tools for Visual Studio 0.4
Simplifying the configuration of Azure DevOps pipelines from within the Visual Studio IDE.

Microsoft JVM Debugger 1.0
Provides support for connecting the Visual Studio debugger to JDWP compatible Java Virtual Machines

Microsoft Library Manager 2.1.113+g422d40002e.RR
Install client-side libraries easily to any web project

Microsoft MI-Based Debugger 1.0
Provides support for connecting Visual Studio to MI compatible debuggers

Microsoft Visual Studio Tools for Containers 1.2
Develop, run, validate your ASP.NET Core applications in the target environment. F5 your application directly into a container with debugging, or CTRL + F5 to edit & refresh your app without having to rebuild the container.

Mono Debugging for Visual Studio 16.10.15 (552afdf)
Support for debugging Mono processes with Visual Studio.

NuGet Package Manager 5.11.0
NuGet Package Manager in Visual Studio. For more information about NuGet, visit https://docs.nuget.org/

Project System Tools 1.0
Tools for working with C#, VisualBasic, and F# projects.

ProjectServicesPackage Extension 1.0
ProjectServicesPackage Visual Studio Extension Detailed Info

Razor (ASP.NET Core) 16.1.0.2122504+13c05c96ea6bdbe550bd88b0bf6cdddf8cde1725
Provides languages services for ASP.NET Core Razor.

SQL Server Data Tools 16.0.62107.28140
Microsoft SQL Server Data Tools

TypeScript Tools 16.0.30526.2002
TypeScript Tools for Microsoft Visual Studio

Visual Basic Tools 3.11.0-4.21403.6+ae1fff344d46976624e68ae17164e0607ab68b10
Visual Basic components used in the IDE. Depending on your project type and settings, a different version of the compiler may be used.

Visual F# Tools 16.11.0-beta.21322.6+488cc578cafcd261d90d748d8aaa7b8b091232dc
Microsoft Visual F# Tools

Visual Studio Code Debug Adapter Host Package 1.0
Interop layer for hosting Visual Studio Code debug adapters in Visual Studio

Visual Studio Container Tools Extensions 1.0
View, manage, and diagnose containers within Visual Studio.

Visual Studio Tools for Containers 1.0
Visual Studio Tools for Containers

VisualStudio.DeviceLog 1.0
Information about my package

VisualStudio.Foo 1.0
Information about my package

VisualStudio.Mac 1.0
Mac Extension for Visual Studio

Xamarin 16.11.000.174 (d16-11@e8f56f1)
Visual Studio extension to enable development for Xamarin.iOS and Xamarin.Android.

Xamarin Designer 16.11.0.17 (remotes/origin/11e0001f0b17269345e80b58fb3adf1ba4efe2cd@11e0001f0)
Visual Studio extension to enable Xamarin Designer tools in Visual Studio.

Xamarin Templates 16.10.5 (355b57a)
Templates for building iOS, Android, and Windows apps with Xamarin and Xamarin.Forms.

Xamarin.Android SDK 11.4.0.5 (d16-11/7776c9f)
Xamarin.Android Reference Assemblies and MSBuild support.
Mono: c633fe9
Java.Interop: xamarin/java.interop@48766c0
ProGuard: Guardsquare/proguard@912d149
SQLite: xamarin/sqlite@85460d3
Xamarin.Android Tools: xamarin/xamarin-android-tools@683f375

Xamarin.iOS and Xamarin.Mac SDK 14.20.0.25 (3b53e529b)
Xamarin.iOS and Xamarin.Mac Reference Assemblies and MSBuild support.

Show/Hide Visual Studio info

Screenshots

Reproduction Link

Shell Styling Problem.zip

Workaround

Navigating to the parent screen from the modal screen using GotoAsync( ".." ) and then going to Home screen from there retains the styling.