[iOS] MSB4044: The "GetMlaunchArguments" task was not given a value for the required parameter "AppBundlePath".

[tivtag]

Description

After adding a file to the Platforms/iOS folder, I receive following build error:
MSB4044: The "GetMlaunchArguments" task was not given a value for the required parameter "AppBundlePath".

Removing the file did not fix the issue.
What do I have to do to fix this issue?

Microsoft (R) Build Engine version 17.1.0-preview-22075-05+b5c435978 for .NET
Copyright (C) Microsoft Corporation. All rights reserved.

  Determining projects to restore...
  All projects are up-to-date for restore.
  MyMauiApp2 -> /Users/paule/Projects/NetMauiTest/MyMauiApp2/bin/Debug/net6.0-ios/ios-arm64/MyMauiApp2.dll
/usr/local/share/dotnet/packs/Microsoft.iOS.Sdk/15.2.200-preview.12.4/targets/Xamarin.Shared.Sdk.targets(1243,3): error MSB4044: The "GetMlaunchArguments" task was not given a value for the required parameter "AppBundlePath". [/Users/paule/Projects/NetMauiTest/MyMauiApp2/MyMauiApp2.csproj]

Build FAILED.

/usr/local/share/dotnet/packs/Microsoft.iOS.Sdk/15.2.200-preview.12.4/targets/Xamarin.Shared.Sdk.targets(1243,3): error MSB4044: The "GetMlaunchArguments" task was not given a value for the required parameter "AppBundlePath". [/Users/paule/Projects/NetMauiTest/MyMauiApp2/MyMauiApp2.csproj]
    0 Warning(s)
    1 Error(s)

Thank you!
Paul Ennemoser

Steps to Reproduce

1. Create new MAUI Project using the command line
2. Configure iOS build by adding following code to the .csproj:

    <PropertyGroup Condition="$(TargetFramework.Contains('-ios'))">
        <RuntimeIdentifier>ios-arm64</RuntimeIdentifier>
		<CodesignKey>YOUR_KEY</CodesignKey>
                <CodesignProvision>YOUR_PROVISIONING_PROFILE_UUID</CodesignProvision>	
                <!--<CodesignEntitlements>Platforms/iOS/Entitlements.plist</CodesignEntitlements>-->  
		<ProvisioningType>manual</ProvisioningType>
    </PropertyGroup>

3. Build and launch on physical iPhone Device:

dotnet build -t:Run -f net6.0-ios -p:_DeviceName=YOUR_DEVICE_NAME

4. App launches successfully on device.
5. Now add a class file to the Platforms/iOS/ folder, such as the following class. I received this error also after adding an Entitlements.plist file.

using ObjCRuntime;
using UIKit;
using CoreNFC;
using Foundation;
using CoreFoundation;
using System.Text;

namespace MyMauiApp2;

public class AsyncNfcReader : NSObject, INFCNdefReaderSessionDelegate
{
    private NFCNdefReaderSession _session;
    private TaskCompletionSource<string> _tcs;

    public Task<string> ScanAsync()
    {
        if (NFCNdefReaderSession.ReadingAvailable)
        {
            throw new InvalidOperationException("Reading NDEF is not available");
        }

        _tcs = new TaskCompletionSource<string>();
        _session = new NFCNdefReaderSession(this, DispatchQueue.CurrentQueue, true);
        _session.BeginSession();

        return _tcs.Task;
    }

    public void DidInvalidate(NFCNdefReaderSession session, NSError error)
    {
        _tcs.TrySetException(new Exception(error?.LocalizedFailureReason));
    }

    public void DidDetect(NFCNdefReaderSession session, NFCNdefMessage[] messages)
    {
        var bytes = messages[0].Records[0].Payload.Skip(3).ToArray();
        var message = Encoding.UTF8.GetString(bytes);
        _tcs.SetResult(message);
    }
}

6. Now the build error occurs.
7. Removing the new file doesn't recover the build error.

Version with bug

Preview 12 (current)

Last version that worked well

Unknown/Other

Affected platforms

iOS

Affected platform versions

iOS 15, VS for MAC Preview 5, .NET SDK 6.0.200, macOS 12.2 on ARM/M1

Did you find any workaround?

No response

Relevant log output

Microsoft (R) Build Engine version 17.1.0-preview-22075-05+b5c435978 for .NET
Copyright (C) Microsoft Corporation. All rights reserved.

  Determining projects to restore...
  All projects are up-to-date for restore.
  MyMauiApp2 -> /Users/paule/Projects/NetMauiTest/MyMauiApp2/bin/Debug/net6.0-ios/ios-arm64/MyMauiApp2.dll
/usr/local/share/dotnet/packs/Microsoft.iOS.Sdk/15.2.200-preview.12.4/targets/Xamarin.Shared.Sdk.targets(1243,3): error MSB4044: The "GetMlaunchArguments" task was not given a value for the required parameter "AppBundlePath". [/Users/paule/Projects/NetMauiTest/MyMauiApp2/MyMauiApp2.csproj]

Build FAILED.

/usr/local/share/dotnet/packs/Microsoft.iOS.Sdk/15.2.200-preview.12.4/targets/Xamarin.Shared.Sdk.targets(1243,3): error MSB4044: The "GetMlaunchArguments" task was not given a value for the required parameter "AppBundlePath". [/Users/paule/Projects/NetMauiTest/MyMauiApp2/MyMauiApp2.csproj]
    0 Warning(s)
    1 Error(s)

[tivtag]

A comment on this Xamarin issue also reports this same build error with no solution: dotnet/xamarin#26 (comment)

[tivtag]

Updating to .NET MAUI Preview 13 and .NET 6.0.2 and creating a new project I still receive this error once I add the AsyncNfcReader.cs to the Platforms/iOS/ folder.

/usr/local/share/dotnet/packs/Microsoft.iOS.Sdk/15.2.301-preview.13.2/targets/Xamarin.Shared.Sdk.targets(1556,3): error MSB4044: The "GetMlaunchArguments" task was not given a value for the required parameter "AppBundlePath".

[codemonkey85]

I'm seeing this error as well.

[andrestalavera]

I have the error:

/usr/local/share/dotnet/packs/Microsoft.iOS.Sdk/15.2.301-preview.13.7/targets/Xamarin.Shared.Sdk.targets(1616,3): error MSB4044: The "GetMlaunchArguments" task was not given a value for the required parameter "AppBundlePath". [/Users/Andres/Projects/XXX-Maui/XXX.Mobile/XXX.Mobile.csproj]

At this day, I use the latest version of framework (SDK 6.0.200) on the last version of VS (2022 Preview, v17 build 7303) and macOS Monterey.

But in my case, I have found a solution:
I have compare a new project with my project (mainly a migration) and I have found one difference... In my *.csproj. I have replace the value of OutputType, from Library to Exe.

[krdmllr]

I have replace the value of OutputType, from Library to Exe.

This fixed it for me, thanks!

[Redth]

Thanks for sharing your answer, yes the OutputType must be Exe.