How to Disable Sound Effects in Android TV app without Muting all System Sounds

I would like to disable sound effects when browsing over RecycleView items and also clicking sounds in an Android TV app. But, I do not want to disable all other sounds (e.g., There is Exoplayer in the app that its output sounds should not be muted).

I noticed there are some other questions similar to this on Stackoverflow and the suggested solutions are:

1. Disable Sound effect in the Layout Files by setting android:soundEffectsEnabled="false" (I put this in every Layout). However, this does not have any effect and there is still clicking and item browsing sound effects.

2. Disable sound effects using AudioManager. I tried the following: audioManager.adjustStreamVolume(AudioManager.STREAM_NOTIFICATION, AudioManager.ADJUST_MUTE, 0); and audioManager.adjustStreamVolume(AudioManager.STREAM_SYSTEM, AudioManager.ADJUST_MUTE, 0); These mute all app sounds including Media sounds.

I would be grateful if someone can help with this issue. Thanks

Finally I found a solution for this problem.

Issue 1: Disabling sound effect on pressing DPAD_CENTER key. I could resolve this issue by programmatically disabling sound effect in CardPresenter (for Leanback ListRowPresenter) and CardAdapter (for RecyclerView).

Issue 2: Disabling sound effect on pressing DPAD navigation keys (DPAD_RIGHT, DPAD_LEFT, ...). Digging into the ViewRootImpl.java class, it turns out that navigation sound is always played without checking the soundEffect flag. Here is parts of the code in ViewRootImpl.java

if (v.requestFocus(direction, mTempRect)) {
     boolean isFastScrolling = event.getRepeatCount() > 0;
     playSoundEffect(
                SoundEffectConstants.getConstantForFocusDirection(direction,
                                            isFastScrolling));
     return true;

So a workaround that I came up with is to override the requestFocus method in my views and always return false to prevent playing sound effect.

Code for Leanback ListRowPresenter:

CardPresenter.java

public class CardPresenter extends Presenter {
     ....

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent) {
         ....

        Context mContext = parent.getContext();

        CustomImageCardView mCardView = new CustomImageCardView(mContext);

        mCardView.setSoundEffectsEnabled(false);

        return new ViewHolder(mCardView);
    }

CustomImageCardView.java

public class CustomImageCardView extends ImageCardView {

    public CustomImageCardView(Context context, int themeResId) {
        super(context, themeResId);
    }

    public CustomImageCardView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    public CustomImageCardView(Context context) {
        super(context);
    }

    public CustomImageCardView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    public boolean requestFocus(int direction, Rect previouslyFocusedRect) {
        super.requestFocus(direction, previouslyFocusedRect);
        return false;
    }
}

Code for RecyclerView:

CardAdapter.java

public class CardAdapter extends RecyclerView.Adapter<CardAdapter.ViewHolder> {
...

@NonNull
    @Override
    public ViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
        View view = mLayoutInflater.inflate(R.layout.recycler_view, viewGroup, false);
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            view.setFocusable(true);
            view.setSoundEffectsEnabled(false);
        }

        mViewHolder = new ViewHolder(view);

        return mViewHolder;
    }

CustomLinearLayout.java (Root View for Recycler View)

public class CustomLinearLayout extends LinearLayout {
    public CustomLinearLayout(Context context) {
        super(context);
    }

    public CustomLinearLayout(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
    }

    public CustomLinearLayout(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    public CustomLinearLayout(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
    }

    @Override
    public void playSoundEffect(int soundConstant) {
        super.playSoundEffect(soundConstant);
    }

    @Override
    public boolean requestFocus(int direction, Rect previouslyFocusedRect) {
        super.requestFocus(direction, previouslyFocusedRect);
        return false;
    }
}