app_Settings/src/com/android/settings/notification/NotificationSoundPreference.java

package com.android.settings.notification;

import android.content.ContentResolver;
import android.content.Context;
import android.media.Ringtone;
import android.media.RingtoneManager;
import android.net.Uri;
import android.os.AsyncTask;
import android.util.AttributeSet;

import com.android.settings.R;
import com.android.settings.RingtonePreference;

public class NotificationSoundPreference extends RingtonePreference {
    private Uri mRingtone;

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

    @Override
    protected Uri onRestoreRingtone() {
        return mRingtone;
    }

    public void setRingtone(Uri ringtone) {
        mRingtone = ringtone;
        updateRingtoneName(mRingtone);
    }

    private void updateRingtoneName(final Uri uri) {
        AsyncTask ringtoneNameTask = new AsyncTask<Object, Void, CharSequence>() {
            @Override
            protected CharSequence doInBackground(Object... params) {
                if (uri == null) {
                    return getContext().getString(com.android.internal.R.string.ringtone_silent);
                } else if (RingtoneManager.isDefault(uri)) {
                    return getContext().getString(R.string.notification_sound_default);
                } else if(ContentResolver.SCHEME_ANDROID_RESOURCE.equals(uri.getScheme())) {
                    return getContext().getString(R.string.notification_unknown_sound_title);
                } else {
                    return Ringtone.getTitle(getContext(), uri, false /* followSettingsUri */,
                            true /* allowRemote */);
                }
            }

            @Override
            protected void onPostExecute(CharSequence name) {
                setSummary(name);
            }
        };
        ringtoneNameTask.execute();
    }
}