MainActivity.java

public List<HwAudioPlayItem> getLocalPlayList(Context context) {
        List<HwAudioPlayItem> playItemList = new ArrayList<>();
        Cursor cursor = null;
        try {
            ContentResolver contentResolver = context.getContentResolver();
            if (contentResolver == null) {
                return playItemList;
            }

            String selection = MediaStore.Audio.Media.IS_MUSIC + "!=0";

            cursor = contentResolver.query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
                    null,
                    selection,
                    null,
                    MediaStore.Audio.Media.TITLE);

            HwAudioPlayItem songItem;
            if (cursor != null) {
                if(!cursor.moveToNext()){
                    //there is no music, do sth
                    return playItemList; //return empty list for now
                }
                else{
                    while(cursor.moveToNext()) {
                        String path = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA));
                        if (new File(path).exists()) {
                            songItem = new HwAudioPlayItem();
                            songItem.setAudioTitle(cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DISPLAY_NAME)));
                            songItem.setAudioId(cursor.getLong(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media._ID)) + "");
                            songItem.setFilePath(path);
                            songItem.setOnline(0);
                            songItem.setIsOnline(0);
                            songItem.setDuration(cursor.getLong(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DURATION)));
                            songItem.setSinger(cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ARTIST)));
                            playItemList.add(songItem);
                        }
                    }
                }
            }
            else{
                Toast.makeText(this, "We have a serious cursor problem here!", Toast.LENGTH_SHORT).show();
            }
        } catch (Exception e) {
            Log.e("TAG,", "EXCEPTION", e);
        } finally {
            if (cursor != null) {
                cursor.close();
            }
        }

        Log.i("LOCALITEMSIZE", "getLocalPlayList: " + playItemList.size());
        return playItemList;
    }