FaceDetectorProcessor.java

// Inside FaceDetectorProcessor.java
public class FaceDetectorProcessor extends VisionProcessorBase<List<Face>> {
    public static class Emotion {
        public final float smileProbability;
        public final float leftEyeOpenProbability;
        public final float rightEyeOpenProbability;
        public Emotion(float smileProbability, float leftEyeOpenProbability, float rightEyeOpenProbability) {
           this.smileProbability = smileProbability;
            this.leftEyeOpenProbability = leftEyeOpenProbability;
           this.rightEyeOpenProbability = rightEyeOpenProbability;
        }
    }
    public interface EmotionListener {
        void onEmotion(Emotion emotion);
    }
    private EmotionListener listener;
    public void setListener(EmotionListener listener) {
       this.listener = listener;
    }
    
    @Override
    protected void onSuccess(@NonNull List<Face> faces, @NonNull GraphicOverlay graphicOverlay) {
        if (!faces.isEmpty() && listener != null) {
            Face face = faces.get(0);
            if (face.getSmilingProbability() != null &&
                    face.getLeftEyeOpenProbability() != null && face.getRightEyeOpenProbability() != null) {
                listener.onEmotion(new Emotion(
                        face.getSmilingProbability(),
                        face.getLeftEyeOpenProbability(),
                        face.getRightEyeOpenProbability()
                ));
            }
        }
    }
}