mediapipe.components.ExternalTextureConverter.setSurfaceTextureAndAttachToGLContext returns null. makes the app crash onResume

I am working on jiuqiant's mediapipe face detection app. I cloned the repo, the app works fine, detects my face but when I pause the app and resumes back, it crashes. with error on this line permalink

converter.setSurfaceTextureAndAttachToGLContext(
previewFrameTexture,
displaySize.getWidth(), 
displaySize.getHeight());

with this log

D/CameraXPreviewHelper: viewSize or frameSize is null.
E/SurfaceView: Exception configuring surface
    java.lang.NullPointerException: Attempt to invoke virtual method 'int android.util.Size.getWidth()' on a null object reference
        at com.example.myfacedetectionapp.MainActivity$1.surfaceChanged(MainActivity.java:146)
        at android.view.SurfaceView.updateSurface(SurfaceView.java:802)
        at android.view.SurfaceView$2.onPreDraw(SurfaceView.java:163)
        at android.view.ViewTreeObserver.dispatchOnPreDraw(ViewTreeObserver.java:977)
        at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:3044)
        at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1845)
        at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:8235)
        at android.view.Choreographer$CallbackRecord.run(Choreographer.java:994)
        at android.view.Choreographer.doCallbacks(Choreographer.java:806)
        at android.view.Choreographer.doFrame(Choreographer.java:738)
        at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:980)
        at android.os.Handler.handleCallback(Handler.java:873)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:226)
        at android.app.ActivityThread.main(ActivityThread.java:7178)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:503)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:942)

It is clear that setSurfaceTextureAndAttachToGLContext is returning null value. Looking at source code (below is the setSurfaceTextureAndAttachToGLContext function in com.google.mediapipe.components.ExternalTextureConverter)

if (viewSize != null && this.frameSize != null) {
    Size optimalSize = this.getOptimalViewSize(viewSize);
    return optimalSize != null ? optimalSize : this.frameSize;
} else {
    Log.d("CameraXPreviewHelper", "viewSize or frameSize is null.");
    return null;
}

it seems that this.frameSize is null. But I dont know how to fix this.

I also tried to hardcode the values

converter.setSurfaceTextureAndAttachToGLContext(previewFrameTexture,200,200);

but it also gives error

I/GLConsumer: [SurfaceTexture-0-13076-0] attachToContext
E/GLConsumer: [SurfaceTexture-0-13076-0] attachToContext: GLConsumer is already attached to a context
E/BpSurfaceComposerClient: Failed to transact (-1)
E/BpSurfaceComposerClient: Failed to transact (-1)
D/GlThread: Stopping GL thread ExternalTextureConverter
D/CaptureSession: Opening capture session.
E/AndroidRuntime: FATAL EXCEPTION: ExternalTextureConverter
    Process: com.example.myfacedetectionapp, PID: 13076
    java.lang.RuntimeException: Error during attachToGLContext (see logcat for details)
        at android.graphics.SurfaceTexture.attachToGLContext(SurfaceTexture.java:289)
        at com.google.mediapipe.components.ExternalTextureConverter$RenderThread.setSurfaceTextureAndAttachToGLContext(ExternalTextureConverter.java:247)
        at com.google.mediapipe.components.ExternalTextureConverter.lambda$setSurfaceTextureAndAttachToGLContext$2$ExternalTextureConverter(ExternalTextureConverter.java:166)
        at com.google.mediapipe.components.-$$Lambda$ExternalTextureConverter$VQm8xcL00VolxXr4rMIgGUKVKnw.run(Unknown Source:8)
        at android.os.Handler.handleCallback(Handler.java:873)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:226)
        at com.google.mediapipe.glutil.GlThread.run(GlThread.java:141)

Is it some version problem. I cant understand.

steps to recreate -

1. Clone repo and run.

2. Thats it. Now try pausing and resuming the app. please let me know if you dont face the error.

Ok using classes given here works. Just place that com directory in your app/src/main.

Just remember to remove the duplicate classes from .aar file in libs directory.