.NET MAUI iOS – Can’t launch the app, crashes on splash screen error

If you are facing issues launching your iOS application in VS Code, then try to analyse the Debug Console of your application.
If you see things like this:

Loaded assembly: /private/var/containers/Bundle/Application/50529075-A03E-45EC-99F6-0A539036E226/app.app/Newtonsoft.Json.dll
Loaded assembly: /private/var/containers/Bundle/Application/50529075-A03E-45EC-99F6-0A539036E226/app.app/System.Reflection.Emit.Lightweight.dll
Loaded assembly: /private/var/containers/Bundle/Application/50529075-A03E-45EC-99F6-0A539036E226/app.app/System.Reflection.Emit.ILGeneration.dll
Loaded assembly: /private/var/containers/Bundle/Application/50529075-A03E-45EC-99F6-0A539036E226/app.app/System.Reflection.Primitives.dll
Loaded assembly: /private/var/containers/Bundle/Application/50529075-A03E-45EC-99F6-0A539036E226/app.app/System.Data.Common.dll
Loaded assembly: /private/var/containers/Bundle/Application/50529075-A03E-45EC-99F6-0A539036E226/app.app/Syncfusion.Maui.Inputs.dll
Loaded assembly: /private/var/containers/Bundle/Application/50529075-A03E-45EC-99F6-0A539036E226/app.app/ZF.Packages.Maui.Fonts.dll
Loaded assembly: /private/var/containers/Bundle/Application/50529075-A03E-45EC-99F6-0A539036E226/app.app/ZF.Packages.Maui.Views.Alerts.dll
Loaded assembly: /private/var/containers/Bundle/Application/50529075-A03E-45EC-99F6-0A539036E226/app.app/Refit.HttpClientFactory.dll
Loaded assembly: /private/var/containers/Bundle/Application/50529075-A03E-45EC-99F6-0A539036E226/app.app/Microsoft.Extensions.Http.dll
Loaded assembly: /private/var/containers/Bundle/Application/50529075-A03E-45EC-99F6-0A539036E226/app.app/MetroLog.Maui.dll

And then your application suddenly crashes showing the splashscreen, then the debugger might be slow.

XCode 15 have problems with debugging. If you have “Connect via network” enabled on your XCode settings under Devices and Simulators, than this might be the problem. Even if you are connecting your phone wired, it starts the application debugging via wifi.
Try updating XCode to 15.4, and update your OS to macOS Sonoma 15.4 aswell

You can countercheck this problem by disabling the wifi on your physical device. In this case the app installs, but crashes instantly when trying to launch it.

Additionally in Visual Studio code the solution you can disable some settings in the C# extension’s settings the Debug > Logging to speed up the loading progress when launching your app.

.NET MAUI + Visual Studio Code: Debugging Cancelled: XCode Not Found

One common issue users face is the “Debugging Cancelled: XCode Not Found” error on macOS. In this blog post, we’ll explore a step-by-step guide to troubleshoot and resolve this vexing problem.

Solution 1: Verify VS Code Command Line Tools Installation
Before diving into complex solutions, let’s start with the basics. Ensure that the VS Code command line tools are correctly installed on your machine. Run the following command in the terminal:

xcode-select --install

This command installs the necessary tools for XCode. After installation, verify that the path is correctly set by running:

xcode-select -p

Ensure that the path points to your XCode installation. If not, set it using the following command:

sudo xcode-select -s /Applications/Xcode.app/Contents/Developer

Solution 2: Force Quit and Relaunch VS Code
Sometimes, issues can be resolved by simply force quitting VS Code and relaunching it. This action ensures a fresh start, eliminating any temporary glitches that might be causing the problem.

Solution 3: Restart VS Code
A restart can work wonders in resolving software-related issues. Save your work, close VS Code, and then relaunch it. This simple step can refresh the IDE and might solve the “Debugging Cancelled: XCode Not Found” issue.

Solution 4: Reinstall .NET MAUI Extension
If the problem persists, the next step is to reinstall the .NET MAUI extension. Extensions can occasionally become corrupted or outdated, leading to compatibility issues. Open the Extensions view in VS Code, locate the .NET MAUI extension, and uninstall it. Afterward, reinstall the latest version from the Visual Studio Code marketplace.

Solution 5: Reinstall Visual Studio Code
If all else fails, consider reinstalling Visual Studio Code. Uninstall the current version, download the latest version from the official website, and perform a clean installation. This ensures that any corrupted files or configurations are completely removed, and you start with a fresh setup.

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Troubleshooting Xamarin and .NET MAUI: iOS Deployment Issues after XCode Upgrade

Are you facing deployment issues with your Xamarin or .NET MAUI iOS app after upgrading XCode? You’re not alone. Many developers encounter the frustrating “/usr/bin/xcrun exited with code 1” error message, coupled with the “actool exited with code 1” and an error about failing to locate a simulator runtime. In this blog post, we’ll delve into this problem and provide you with a solution to get your iOS app deployment back on track.

Understanding the Problem

After upgrading XCode to a newer version, you may notice that you can’t deploy your Xamarin or .NET MAUI iOS app to physical iOS devices, and the simulator targets are mysteriously missing from the drop-down menu where you select deployment targets. This issue can be perplexing and hinder your development workflow.

The error message you encounter typically looks something like this:

Resolution

To tackle this deployment challenge, you should delve into your XCode configuration and confirm that the iOS platform is both accessible and correctly installed on your development machine. Follow these steps:

  1. Launch XCode on your Mac.
  2. Click on “XCode” in the top menu bar and choose “Preferences.” This will open the XCode preferences window.
  3. Within the preferences window, select the “Platforms” section. Here, you’ll find the key settings related to platform configuration.
  4. After you’ve confirmed that all the required iOS components are installed, close and restart Visual Studio (or your preferred development environment).
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.NET MAUI: iOS ListView disappearing cells

In this article, we will delve into a persistent .NET MAUI issue affecting ListViews on the iOS platform in .NET 7 builds. While the .NET 8 preview has addressed this issue, developers seeking a solution can employ the BindableLayout as a temporary workaround. We’ll also explore the concept of BindableLayout and touch on the CachingStrategy within ListViews.

The Problem: Disappearing Cells in ListViews on iOS

The issue at hand revolves around the behavior of ListViews on the iOS platform in .NET 7 builds. As users scroll through the list elements, the ListView cells mysteriously disappear, causing a jarring experience. While the .NET 8 preview has resolved this vexing problem, the official release is still pending, leaving developers seeking immediate solutions.

The Workaround: BindableLayout within ScrollView

A viable workaround to mitigate the disappearing cell issue involves utilizing the BindableLayout within a ScrollView. The BindableLayout.ItemSource property can be harnessed to mimic the ListView’s behavior. However, it’s crucial to acknowledge that this solution might not deliver the same performance as a native ListView.

Example Code

Here’s how you can implement the BindableLayout workaround:

<ScrollView>
    <StackLayout>
        <BindableLayout.ItemsSource>
            <x:Array Type="{x:Type local:ItemModel}">
                <local:ItemModel Name="Item 1" />
                <local:ItemModel Name="Item 2" />
                <local:ItemModel Name="Item 3" />
                <!-- Add more items here -->
            </x:Array>
        </BindableLayout.ItemsSource>
        <BindableLayout.ItemTemplate>
            <DataTemplate>
                <Label Text="{Binding Name}" />
            </DataTemplate>
        </BindableLayout.ItemTemplate>
    </StackLayout>
</ScrollView>

BindableLayout: A Glimpse

BindableLayout is a versatile feature within the .NET MAUI framework that allows developers to easily bind collections to layout controls. It’s an excellent alternative when dealing with scenarios where a native ListView isn’t performing optimally or in cases like the aforementioned issue. BindableLayout empowers developers to achieve the desired UI layout while maintaining data synchronization.

Use BindableLayout when you want more control over the layout of your items, need to create a dynamic UI with varying layouts, and don’t necessarily require built-in performance optimizations.

Understanding CachingStrategy within ListViews

ListViews in .NET MAUI come with a property known as CachingStrategy. This property determines how the ListView should cache its visual elements, significantly influencing performance. There are three options:

  1. RecycleElement: This strategy reuses existing cells, enhancing memory usage and rendering speed. However, it might pose issues when complex cell layouts are used.
  2. RetainElement: This strategy preserves cells for the duration of the ListView’s existence. While memory consumption can be higher, it can be useful for more intricate cell layouts.
  3. None: In this strategy, no caching is employed, causing cells to be created and destroyed frequently. While it minimizes memory usage, it can have an adverse impact on performance.

Conclusion

While the .NET MAUI framework continues to evolve, issues like the disappearing ListView cells on iOS in .NET 7 builds are inevitable. Developers eagerly anticipate the benefits that .NET 8 will bring, including the resolution of this particular problem. In the interim, the BindableLayout within a ScrollView offers a workaround that replicates the ListView’s behavior, albeit with potential performance differences. By understanding concepts like BindableLayout and the CachingStrategy within ListViews, developers can navigate these challenges while continuing to create engaging and efficient cross-platform applications. Stay tuned for the official .NET 8 release and more innovations that will undoubtedly enhance the .NET MAUI experience.

https://github.com/dotnet/maui/issues/11640

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.NET MAUI iOS Bug – Release Mode Bindings Not Working

Software bugs can sometimes manifest in specific environments or platforms, leading to unexpected behavior. In this blog post, we will discuss a bug in .NET MAUI specifically affecting iOS platforms. The bug causes bindings between Views and ViewModels to fail in Release mode, resulting in empty Views without the expected data. We’ll explore the symptoms of this bug and present a workaround that involves utilizing the XamlCompilation attribute with the Skip option.

Symptoms

The bug we are addressing affects the binding functionality in .NET MAUI apps running on iOS platforms in Release mode. When encountering this issue, Views fail to bind with their associated ViewModels, resulting in empty Views that appear as if no BindingContext is present.

What is XamlCompilation?

XamlCompilation is an attribute provided by Xamarin.Forms that allows developers to specify how XAML files should be compiled. It offers three options: None, XamlC, and Skip.

  • None: The default option. XAML files are not compiled individually and are interpreted at runtime.
  • XamlC: XAML files are compiled ahead-of-time into IL code, improving performance by eliminating the need for runtime interpretation.
  • Skip: XAML files are skipped from the compilation process and are interpreted at runtime, similar to the None option.

Providing workaround

To mitigate this bug, we can utilize the XamlCompilation attribute with the Skip option on the affected Views. This attribute is used to control the compilation behavior of XAML files in .NET MAUI applications.

Identify the Affected View First, identify the View(s) in your .NET MAUI app that are experiencing the binding issue specifically on iOS platforms in Release mode. Add XamlCompilation Attribute Add the XamlCompilation attribute to the affected View’s code-behind file. Set the attribute value to Skip to instruct the compiler to exclude the associated XAML file from the compilation process.

[XamlCompilation(XamlCompilationOptions.Skip)]
public partial class MyAffectedView : ContentView
{
    // ...
}

Ensure that the affected View is properly updated with the XamlCompilation attribute. Test the application in Release mode on iOS to confirm that the bindings are now functioning as expected and the Views are populated with the appropriate data.

Keep in mind that while this workaround provides a solution for the bug, it’s important to regularly check for updates from the .NET MAUI team, as they may address and fix this issue in future releases. Additionally, test your app thoroughly after applying the workaround to ensure the expected functionality and behavior across different platforms.

This content has 1 year. Some of the information in this post may be out of date or no longer work. Please, read this page keeping its age in your mind.