Android 如何从ContentResolver查询中获取跟踪Uri？

我用下面的代码遍历手机的内存

ContentResolver contentResolver = getContentResolver();
    String[] columns = {
            MediaColumns._ID,
            MediaColumns.TITLE,
        AudioColumns.DURATION,

    };
    final String where = MediaStore.Audio.Media.IS_MUSIC + "=1";

    Cursor cursor = contentResolver.query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,columns, where, null, null);

    while(cursor.moveToNext()) {
        String urp = cursor.getString(cursor.getColumnIndex(MediaColumns._ID));
        String title = cursor.getString(cursor.getColumnIndex(MediaColumns.TITLE));
        Long duration = cursor.getLong(cursor.getColumnIndex(AudioColumns.DURATION));
    }

现在我的问题是，如何获取游标项traveresed的uri，如 第一次运行时，我存储了id、标题、持续时间等元数据，我还想 存储跟踪URI，我还想将该URI从content//scheme转换为filescheme

任何帮助都将是巨大的 谢谢

String.valueOf(cur.getColumnIndex(android.provider.MediaStore.MediaColumns.DATA)));