Java 在android中，如何在从服务器下载视频文件的过程中添加铃声

在这段代码中，当视频从服务器下载到移动设备时，我需要应用叮当声

code : This the main activity which is java file where the videos are downloaded from server and getting situated in android device and will be played in video view  

MainActivity.java 软件包ivmshd.mcu.com.demo

import android.app.DownloadManager;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.database.Cursor;
import android.media.MediaPlayer;
import android.net.Uri;
import android.os.Environment;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageView;
import android.widget.MediaController;
import android.widget.VideoView;

import java.io.File;

import static android.R.attr.path;

public class MainActivity extends AppCompatActivity {
private long enqueue;
private DownloadManager dm;
 @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
 BroadcastReceiver receiver = new BroadcastReceiver() {
            @Override
            public void onReceive(Context context, Intent intent) {
                String action = intent.getAction();
                if (DownloadManager.ACTION_DOWNLOAD_COMPLETE.equals(action)) {
                    long downloadId = intent.getLongExtra(DownloadManager.EXTRA_DOWNLOAD_ID, 0);
                    DownloadManager.Query query = new DownloadManager.Query();
                    query.setFilterById(enqueue);
                    Cursor c = dm.query(query);
                    if (c.moveToFirst()) {
                        int columnIndex = c.getColumnIndex(DownloadManager.COLUMN_STATUS);
                        if (DownloadManager.STATUS_SUCCESSFUL == c.getInt(columnIndex)) {


                            VideoView view= (VideoView) findViewById(R.id.videoView);

    enter code here

                            String uriString = c.getString(c.getColumnIndex(DownloadManager.COLUMN_LOCAL_URI));

                            view.setVideoURI(Uri.parse(uriString));
                        }
                    }
                }
            }
        };

        registerReceiver(receiver, new IntentFilter(
                DownloadManager.ACTION_DOWNLOAD_COMPLETE));
    }

    public void onClick(View view) {

        dm = (DownloadManager) getSystemService(DOWNLOAD_SERVICE);

                DownloadManager.Request request =new DownloadManager.Request(Uri.parse("http://eZeeReview.com/login/pages/examples/video/1.mp4"));
        enqueue = dm.enqueue(request);
        final VideoView videoView;

        videoView = (VideoView) findViewById(R.id.videoView);
        Uri video = Uri.parse("http://eZeeReview.com/login/pages/examples/video/1.mp4");
        videoView.setVideoURI(video);
        videoView.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
            @Override
            public void onPrepared(MediaPlayer mp) {
                mp.setLooping(true);
                videoView.start();
            }
        });

    }
    public void showDownload(View view) {
        Intent i = new Intent(Intent.ACTION_VIEW);
        i.setAction(DownloadManager.ACTION_VIEW_DOWNLOADS);

        startActivity(i);
    }

}


XML File: In this code the widgets are applied

widgets are like Video view and 2 buttons 

在视频视图中播放视频的位置。此视频是从服务器获取的视频

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="fill_parent"
    android:layout_height="fill_parent">

    <Button android:text="Start Download" android:id="@+id/button1"
        android:layout_width="wrap_content" android:layout_height="wrap_content"
        android:onClick="onClick"></Button>

    <Button android:text="View Downloads" android:id="@+id/button2"
        android:layout_width="wrap_content" android:layout_height="wrap_content"
        android:onClick="showDownload"></Button>

    <VideoView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/videoView" />

</LinearLayout>

什么是

铃声

？这是一些音频吗？叮当就像是在文件传输过程中使用的，即如果视频是从服务器下载的，在这段时间内，叮当将以视频的形式播放。你可以查看上面的链接，了解abt，好吧，现在我发现这不是我的线索。