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[Bug] ListView the first item isn't displayed initially #14048

Open ppetrov opened 3 years ago

ppetrov commented 3 years ago

Description

ListView the first item isn't displayed initially on iOS. You need to scroll it to see the first item.

Steps to Reproduce

  1. Launch the attached project on iOS

Expected Behavior

The first item to be displayed.

Actual Behavior

The second item is displayed at the first position. Note that even when you scroll to view the top of the list, the first item appears but there's no separator between the first and the second item.

Basic Information

Environment

Show/Hide Visual Studio info ``` Microsoft Visual Studio Professional 2019 Version 16.9.2 VisualStudio.16.Release/16.9.2+31112.23 Microsoft .NET Framework Version 4.8.04161 Installed Version: Professional Visual C++ 2019 00435-60000-00000-AA571 Microsoft Visual C++ 2019 ASP.NET and Web Tools 2019 16.9.688.6828 ASP.NET and Web Tools 2019 ASP.NET Core Razor Language Services 16.1.0.2112521+5741df381174d72f08e3632bb99f52e8635b6a1a Provides languages services for ASP.NET Core Razor. ASP.NET Web Frameworks and Tools 2019 16.9.688.6828 For additional information, visit https://www.asp.net/ Azure App Service Tools v3.0.0 16.9.688.6828 Azure App Service Tools v3.0.0 C# Tools 3.9.0-6.21160.10+59eedc33d35754759994155ea2f4e1012a9951e3 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 JetBrains ReSharper 2021.1 EAP 8 Build 211.0.20210316.112827-eap08 JetBrains ReSharper package for Microsoft Visual Studio. For more information about ReSharper, visit http://www.jetbrains.com/resharper. Copyright © 2021 JetBrains, Inc. 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 C++ Wizards 1.0 Microsoft Visual C++ Wizards Microsoft Visual Studio Tools for Containers 1.1 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. Microsoft Visual Studio VC Package 1.0 Microsoft Visual Studio VC Package Mono Debugging for Visual Studio 16.9.7 (df23ba6) Support for debugging Mono processes with Visual Studio. NuGet Package Manager 5.9.0 NuGet Package Manager in Visual Studio. For more information about NuGet, visit https://docs.nuget.org/ Office Developer Tools for Visual Studio 16.0.30502.00 Microsoft Office Developer Tools for Visual Studio ProjectServicesPackage Extension 1.0 ProjectServicesPackage Visual Studio Extension Detailed Info SQL Server Data Tools 16.0.62103.10080 Microsoft SQL Server Data Tools TypeScript Tools 16.0.30201.2001 TypeScript Tools for Microsoft Visual Studio Visual Basic Tools 3.9.0-6.21160.10+59eedc33d35754759994155ea2f4e1012a9951e3 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 16.9.0-beta.21102.9+7ce7132f1459095e635194d09d6f73265352029a 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 Workflow Manager Tools 1.0 1.0 This package contains the necessary Visual Studio integration components for Workflow Manager. Xamarin 16.9.000.273 (d16-9@1bba9e0) Visual Studio extension to enable development for Xamarin.iOS and Xamarin.Android. Xamarin Designer 16.9.0.316 (remotes/origin/d16-9@fdbf64026) Visual Studio extension to enable Xamarin Designer tools in Visual Studio. Xamarin Templates 16.9.68 (8e9b569) Templates for building iOS, Android, and Windows apps with Xamarin and Xamarin.Forms. Xamarin.Android SDK 11.2.2.1 (d16-9/877f572) Xamarin.Android Reference Assemblies and MSBuild support. Mono: 5e9cb6d Java.Interop: xamarin/java.interop/d16-9@54f8c24 ProGuard: Guardsquare/proguard/v7.0.1@912d149 SQLite: xamarin/sqlite/3.34.1@daff8f4 Xamarin.Android Tools: xamarin/xamarin-android-tools/d16-9@d210f11 Xamarin.iOS and Xamarin.Mac SDK 14.14.2.5 (3836759d4) Xamarin.iOS and Xamarin.Mac Reference Assemblies and MSBuild support. ```

Build Logs

Screenshots

Reproduction Link

LVItemsIssue.zip

Workaround

Initially the item with caption '0' isn't displayed IMG_0021

When scrolled the item is displayed. Note that between item '0' and item '1' there's no separator IMG_0022

jsuarezruiz commented 3 years ago

The SelectedItem is set to the first item (0). Without setting the first element, the behavior is the expected, setting the SelectedItem we get the behavior described by the issue.