Add compile time exclusion

[kaltinril]

This fixes an issue where because Monogame now comes with this extension method, it fails if someone has Monogame and Extended functionality mixed on in their ContentTypeReader class.

https://github.com/MonoGame/MonoGame/blob/8df1e3edb3076b010822d2c9cf019f2f7f5f70a0/MonoGame.Framework/Content/ContentReaderExtensions.cs#L24

Example code that will break, can't have both of these using statements. To fix I've simply made it so Monogame.Extended doesn't add these methods during compile time.

using Microsoft.Xna.Framework.Content;
using MonoGame.Extended.Content;

namespace ContentManager_Extensions
{
    public class ReaderExample : ContentTypeReader<ReaderExampleClass>
    {
        protected override ReaderExampleClass Read(ContentReader reader, ReaderExampleClass existingInstance)
        {
            var graphicsDevice = reader.GetGraphicsDevice();

            return new ReaderExampleClass("exampletexture.png");
        }
    }

    public class ReaderExampleClass
    {
        public string TextureName { get; set; }

        public ReaderExampleClass(string textureName)
        {
            this.TextureName = textureName;
        }
    }
}

[nkast]

The extension exist on KNI as well.
https://github.com/kniEngine/kni/blob/02e6accab0615535b6adb15075b013a28ada9a58/src/Xna.Framework.Graphics/Graphics/Utilities/ContentReaderExtensions.cs#L33-L41
So if you include it, it will have the same conflict as you get in MonoGame.

The extension will not work on FNA because ContentReader doesn't have a graphicsDevice field.
https://github.com/FNA-XNA/FNA/blob/master/src/Content/ContentReader.cs
The reflection will no longer work on MonoGame/KNI either. The field was removed in MonoGame/MonoGame#6913

The proper way to get a graphicsDevice inside a ContentTypeReader, is through the ServiceProvider.

  var graphicsDeviceService = contentReader.ContentManager.GetService(typeof(IGraphicsDeviceService)) as IGraphicsDeviceService;
  var graphicsDevice = graphicsDeviceService.GraphicsDevice;

[kaltinril]

Interesting, I'm not trying to add it, I'm trying to exclude it.

It sounds like you're saying it's either in or won't work in eveything (fna, kni, monogame).

If thats true, I say it should be removed from extended.

This method extension is in monogame.

I don't know if "monogame/kni" is different than "kni". So I'm not sure what you mean in your last statement, as monogame does have this method.

[nkast]

You are excluding it from monogame because of a conflct. The same method exist on KNI, so you have to exclude it from KNI as well.

Which leaves FNA, where the reflection will fail.

I think it's ok to remove it, as it didn't work for some time now. Unless it's used from Extended internally.

[AristurtleDev]

I could be adjusted to remove reflection so it's compatible with FNA. This is also a step that will need to be looked at in the future to ensure MGE is AoT compatible once MonoGame removes the BRUTE dependency.

So we would need to adjust it to the service pattern like MonoGame and KNI has implemented like suggested by @nkast , but only for FNA

The FieldInfo _contentReaderGraphicsDeviceFieldInfo isn't used anywhere except in that method as a static cache after the first time it's called, so that would need to be removed, then the method updated to

#if FNA
public static GraphicsDevice GetGraphicsDevice(this ContentReader contentReader)
{
    var serviceProvider = contentReader.ContentManager.ServiceProvider;
    var graphicsDeviceService = serviceProvider.GetService(typeof(IGraphicsDeviceService)) as IGraphicsDeviceService;
           
    if (graphicsDeviceService == null)
    {
        throw new InvalidOperationException("No Graphics Device Service");
    }

    return graphicsDeviceService.GraphicsDevice;
}
#endif

Since FNA's goal is to remain 1:1 compatible with the XNA Api, i don't see them adding this extension method in.

[kaltinril]

Sounds good @nkast and @AristurtleDev. This small change spawned because I was trying to validate and update the documentation for ContentManager Extensions in Monogame.Extended .

https://www.monogameextended.net/docs/features/contentmanager/contentManager-extensions/

Please let me know if there are any other changes you wish, I'm going to notate the section in the Extended docs to indicate that it only applies for FNI.

[nkast]

Looks good. Thanks.

[AristurtleDev]

Thanks @kaltinril