[MAUI] Update the bindings to work in .net 6+ (Maui)

[AdamDiament]

This might need to be a separate repo, as upgrading the target framework to add maui support will break Xamarin forms. I haven't decided what is best yet. Thoughts welcome, in particular PRs or ways to get XF-Maui side-by-side working.

Possible useful resources

https://learn.microsoft.com/en-us/events/dotnetconf-focus-on-maui/binding-native-libraries-for-dotnet-maui

[AdamDiament]

The first step will be to make sure all the referenced nuget dependencies support .net6 android/ios

I've had an initial audit, most do thankfully. There are two that don't:

1. Xamarin.Google.Android.Material 1.3.1. Upgrading to 1.6.1 should provide a version that compiles for .net 6 - it might require adding a remove node like this but nothing major

   <remove-node path="/api/package[@name='com.zipow.videobox.viewmodel.phone']/class[@name='PhoneSettingCallForwardViewModel']"/>

2. Com.Airbnb.Xamarin.Forms.Lottie 4.1.0 - there is an issue on the lottie repo requesting .net 6 support here if you want to bump it that would be helpful

[AdamDiament]

I think we need to create an "Android Java Library Binding" for the jar to support MAUI droid. Does anyone know the build action needed for the aar? LibraryProjectZip is no longer available, which is the xamarin build action to be able to access both code and resources from the .aar.

[mdima]

Hi Adam,
I passed through this already for another project. You should set the Build Action to "AndroidLibrary" for the .aar files.

Have a good day,
Michele

[AdamDiament]

Hey @mdima, nice to hear from you! Thanks for the tip. I've renamed the repo now to a more generic dotnet name, and started the process of adding MAUI support in a separate sln.

For android, I have the aar loading now I've set it to the correct build configuration. I am working through some weird missing resource build failures. Have not started iOS yet. If you had any time to jump in and help with either, we'd love the support!

[AdamDiament]

The lib projects for android are both building now.

Trying to build the sample app for android, and getting this:

I remember dealing with similar issues during the Xamarin days. Not sure of the solution for MAUI. Adding the missing color resources in manually just throws up a whole bunch of new missing resource build errors.

I'm seeing if perhaps we are missing a required nuget package.

[AdamDiament]

Captain's log: star-date 24th July, Tellus

I added the nuget packages to match the xamarin version, and still get the same missing resource errors. I also added a version of the lottieMaui repo for android only. No dice.

As of right now, stuck!

[AdamDiament]

C.C @icalderond if you have any insight

[AdamDiament]

Ok with much back and forth I think that I have narrowed the problem down to these two nuget packages, neither of which support .net6+ yet. (Funnily enough they are by the same author, the awesome https://github.com/martijn00)

<PackageReference Include="Com.Airbnb.Xamarin.Forms.Lottie">
			<Version>4.1.0</Version>
</PackageReference>
<PackageReference Include="Xamarin.ExoPlayerSlim">
			<Version>2.16.1.12</Version>
</PackageReference>

ExoPlayer slim has plans to support Maui, I raised this issue here and they say it should be available soon. As an alternative, I tried using the full-fat exoplayer nuget, which does support .net6. It made me add a new remove node in the MetaData.xml but otherwise compiled. When referencing it via a .net maui project, I saw the missing resource errors. I don't yet know if that is because I added the full fat exoplayer, or if they are coming from missing Lottie stuff...

As for Lottie, there is a PR here to upgrade for net6 Baseflow/LottieXamarin#379 - apparently it works for droid but not for iOS yet. The PR has gone stale though and there is no sign of an upgrade. Perhaps someone with more iOS skills than me might consider jumping in.

A couple of possible hail-mary alternatives:

• Skia Sharp has a nuget for lottie in pre-release. I wonder if this would add the necessary code to make the MAUI sample app compile. Seems unlikely but might be worth trying.

SkiaSharp.Skottie --version 2.88.3

When I add SkiaLottie the resource errors go away (or get hidden) but I get these errors

I might be able to shim these, will try tomorrow...

Tried the shim. These two resource errors went away, but then all the original resource errors reappeared. My current working theory is that they are caused by a dependency in exoplayer full-fat. So I'm going to wait for the slim binding to be available and try again. If after putting that back in, we still get resource errors, they must be because of Lottie.

• There is a LottieMaui repo here Nuget package Csaba8472/LottieMaui#1 - (I added this issue. There is no nuget yet. I tried integrating the project code directly but had no success. The author describes how he did it here https://dev.to/csaba8472/binding-lottie-or-any-other-swift-framework-with-ui-in-maui-543m

[AdamDiament]

The missing resources are all defined in ZoomCommonLib. I'm wondering if there is an issue with how maui handles one binding library that references another. (HeadProject => MobileRTC => ZoomCommonLib)

Adding all the resources from zoomcommon lib manually into my maui android resources, just throws up more missing resource errors though. Mainly from exoplayer... I'm using the full fat library. Maybe I need to look at its dependencies and manually include them

.... nope, not that!

[samirgcofficial]

Any updates for the .net maui support?

[AdamDiament]

No, I am still working through the issues as described in the comments

[AdamDiament]

An update, although without good news, is that on the MAUIFY branch I used the full fat exoplayer, and a version of lottie that compiled for .net 7, which I hoped would clear up the remaining issues. Yet I still get the exact same errors, so either one of those packages is causing problems, or another package is the problem, or there is a deeper problem with MAUI bindings that I don't understand. If anyone has any wisdom to share, I am all ears! I wish the error messages were more informative - I am certain that the actual error is nothing to do with missing resources, rather that the compile step fails for the actual reason before the resources can be included, and the real error is swallowed somewhere.