Android skia canvas.DrawImage has no effect with SkiaBitmapExportContext

[philipag]

Description

When using SKCanvasView, one can use canvas.DrawImage and image is displayed. However, when using SkiaBitmapExportContext.Canvas.DrawImage, nothing is rendered into the canvas.

Please see the attached sample for details. It saves the file badOutputWithoutImage.png which should contain the Android robot image but does not. It only shows the white background which was rendered into the canvas.

skiaBug.zip

Steps to Reproduce

1. Build the attached sample, build and run on an emulator.
2. Use Android Studio to navigate to and view the output file "badOutputWithoutImage.png"
3. The file does not contain the android robot image that was painted into the canvas (it should).

Link to public reproduction project repository

attached

Version with bug

6.0.486 (current)

Last version that worked well

Unknown/Other

Affected platforms

Android, I was not able test on other platforms

Affected platform versions

Android 12

Did you find any workaround?

no

Relevant log output

No response

[mattleibow]

SkiaBitmapExportContext is part of maui graphics so the bug is there.

[ghost]

We've moved this issue to the Backlog milestone. This means that it is not going to be worked on for the coming release. We will reassess the backlog following the current release and consider this item at that time. To learn more about our issue management process and to have better expectation regarding different types of issues you can read our Triage Process.

[ksd050]

This has been outstanding for some time now, is there any hope that it will be resolved? Alternatively, has anyone found a workaround?

[homeyf]

Verified this issue with Visual Studio Enterprise 17.8.0 Preview 1.0. Can repro on android with sample project. skiaBug.zip

[softlion]

The cause of this issue is that code in SkiaCanvas.DrawImage used by MySkiaBitmapExportContext, which tries to convert the IImage into a SkiaImage.

But most of the time IImage is a PlatformImage, not a SkiaImage. The above conversion results becomes null, and the whole call is a noop.

A simple fix would be to replace the cast by SkiaImage into a cast by PlatformImage.

[softlion]

A temporary workaround:

#if ANDROID
using SkiaSharp.Views.Android;
#elif IOS
using SkiaSharp.Views.iOS;
#endif

            if (image is not SkiaImage && image is PlatformImage platformImage)
            {
                var platformRepresentation = platformImage.PlatformRepresentation;
                var newImage = new SkiaImage(SKBitmap.FromImage(platformRepresentation.ToSKImage()));
                image.Dispose();
                image = newImage;
            }