Android实现在线播放音乐

分享一下我老师大神的人工智能教程！零基础，通俗易懂！http://blog.csdn.net/jiangjunshow

也欢迎大家转载本篇文章。分享知识，造福人民，实现我们中华民族伟大复兴！

               

Android实现在线播放音乐

2014年3月10日

hello，小伙伴们，3月份珊珊来迟的第一篇博客，最近小巫在找工作，加上又生病了，就没有太多精力去写博客了。今天拖着病发表一篇之前已经实现的在线播放音乐效果，在线播放音乐并不难，也就是传入的Url是一个网络地址。这里我要实现一个可以进行网络缓冲的在线音乐播放。

效果实现：

本篇博客是在多线程下载那篇博客增加在线播放音乐实现，下面是提供项目下载地址：

http://download.csdn.net/detail/wwj_748/7018493

下面介绍具体实现过程：

定义一个具有缓冲效果的播放器：Player

我们看到的缓冲效果，是通过设置拖动条SeekBar的二级进度实现的，这就要设置MediaPlayer的缓冲更新的监听了。

具体代码实现：

package com.wwj.download.util;import java.io.IOException;import java.util.Timer;import java.util.TimerTask;import android.media.AudioManager;import android.media.MediaPlayer;import android.media.MediaPlayer.OnBufferingUpdateListener;import android.media.MediaPlayer.OnCompletionListener;import android.media.MediaPlayer.OnPreparedListener;import android.os.Handler;import android.util.Log;import android.widget.SeekBar;public class Player implements OnBufferingUpdateListener, OnCompletionListener,  OnPreparedListener { public MediaPlayer mediaPlayer; // 媒体播放器 private SeekBar seekBar; // 拖动条 private Timer mTimer = new Timer(); // 计时器 // 初始化播放器 public Player(SeekBar seekBar) {  super();  this.seekBar = seekBar;  try {   mediaPlayer = new MediaPlayer();   mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);// 设置媒体流类型   mediaPlayer.setOnBufferingUpdateListener(this);   mediaPlayer.setOnPreparedListener(this);  } catch (Exception e) {   e.printStackTrace();  }  // 每一秒触发一次  mTimer.schedule(timerTask, 0, 1000); } // 计时器 TimerTask timerTask = new TimerTask() {  @Override  public void run() {   if (mediaPlayer == null)    return;   if (mediaPlayer.isPlaying() && seekBar.isPressed() == false) {    handler.sendEmptyMessage(0); // 发送消息   }  } }; Handler handler = new Handler() {  public void handleMessage(android.os.Message msg) {   int position = mediaPlayer.getCurrentPosition();   int duration = mediaPlayer.getDuration();   if (duration > 0) {    // 计算进度（获取进度条最大刻度*当前音乐播放位置 / 当前音乐时长）    long pos = seekBar.getMax() * position / duration;    seekBar.setProgress((int) pos);   }  }; }; public void play() {  mediaPlayer.start(); } /**  *   * @param url  *            url地址  */ public void playUrl(String url) {  try {   mediaPlayer.reset();   mediaPlayer.setDataSource(url); // 设置数据源   mediaPlayer.prepare(); // prepare自动播放  } catch (IllegalArgumentException e) {   e.printStackTrace();  } catch (SecurityException e) {   e.printStackTrace();  } catch (IllegalStateException e) {   e.printStackTrace();  } catch (IOException e) {   e.printStackTrace();  } } // 暂停 public void pause() {  mediaPlayer.pause(); } // 停止 public void stop() {  if (mediaPlayer != null) {   mediaPlayer.stop();   mediaPlayer.release();   mediaPlayer = null;  } } // 播放准备 @Override public void onPrepared(MediaPlayer mp) {  mp.start();  Log.e("mediaPlayer", "onPrepared"); } // 播放完成 @Override public void onCompletion(MediaPlayer mp) {  Log.e("mediaPlayer", "onCompletion"); } /**  * 缓冲更新  */ @Override public void onBufferingUpdate(MediaPlayer mp, int percent) {  seekBar.setSecondaryProgress(percent);  int currentProgress = seekBar.getMax()    * mediaPlayer.getCurrentPosition() / mediaPlayer.getDuration();  Log.e(currentProgress + "% play", percent + " buffer"); }}

package com.wwj.download;import java.io.File;import java.io.UnsupportedEncodingException;import java.net.URLEncoder;import android.app.Activity;import android.os.Bundle;import android.os.Environment;import android.os.Handler;import android.os.Message;import android.view.View;import android.widget.Button;import android.widget.EditText;import android.widget.ProgressBar;import android.widget.SeekBar;import android.widget.SeekBar.OnSeekBarChangeListener;import android.widget.TextView;import android.widget.Toast;import com.wwj.download.util.Player;import com.wwj.net.download.DownloadProgressListener;import com.wwj.net.download.FileDownloader;public class MainActivity extends Activity { private static final int PROCESSING = 1; private static final int FAILURE = -1; private EditText pathText; // url地址 private TextView resultView; private Button downloadButton; private Button stopButton; private ProgressBar progressBar; private Button playBtn; private Player player; // 播放器 private SeekBar musicProgress; // 音乐进度 private Handler handler = new UIHandler(); private final class UIHandler extends Handler {  public void handleMessage(Message msg) {   switch (msg.what) {   case PROCESSING: // 更新进度    progressBar.setProgress(msg.getData().getInt("size"));    float num = (float) progressBar.getProgress()      / (float) progressBar.getMax();    int result = (int) (num * 100); // 计算进度    resultView.setText(result + "%");    if (progressBar.getProgress() == progressBar.getMax()) { // 下载完成     Toast.makeText(getApplicationContext(), R.string.success,       Toast.LENGTH_LONG).show();    }    break;   case FAILURE: // 下载失败    Toast.makeText(getApplicationContext(), R.string.error,      Toast.LENGTH_LONG).show();    break;   }  } } @Override protected void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.main);  pathText = (EditText) findViewById(R.id.path);  resultView = (TextView) findViewById(R.id.resultView);  downloadButton = (Button) findViewById(R.id.downloadbutton);  stopButton = (Button) findViewById(R.id.stopbutton);  progressBar = (ProgressBar) findViewById(R.id.progressBar);  ButtonClickListener listener = new ButtonClickListener();  downloadButton.setOnClickListener(listener);  stopButton.setOnClickListener(listener);  playBtn = (Button) findViewById(R.id.btn_online_play);  playBtn.setOnClickListener(listener);  musicProgress = (SeekBar) findViewById(R.id.music_progress);  player = new Player(musicProgress);  musicProgress.setOnSeekBarChangeListener(new SeekBarChangeEvent()); } private final class ButtonClickListener implements View.OnClickListener {  @Override  public void onClick(View v) {   switch (v.getId()) {   case R.id.downloadbutton: // 开始下载    // http://abv.cn/music/光辉岁月.mp3，可以换成其他文件下载的链接    String path = pathText.getText().toString();    String filename = path.substring(path.lastIndexOf('/') + 1);    try {     // URL编码（这里是为了将中文进行URL编码）     filename = URLEncoder.encode(filename, "UTF-8");    } catch (UnsupportedEncodingException e) {     e.printStackTrace();    }    path = path.substring(0, path.lastIndexOf("/") + 1) + filename;    if (Environment.getExternalStorageState().equals(      Environment.MEDIA_MOUNTED)) {     // File savDir =     // Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MOVIES);     // 保存路径     File savDir = Environment.getExternalStorageDirectory();     download(path, savDir);    } else {     Toast.makeText(getApplicationContext(),       R.string.sdcarderror, Toast.LENGTH_LONG).show();    }    downloadButton.setEnabled(false);    stopButton.setEnabled(true);    break;   case R.id.stopbutton: // 暂停下载    exit();    Toast.makeText(getApplicationContext(),      "Now thread is Stopping!!", Toast.LENGTH_LONG).show();    downloadButton.setEnabled(true);    stopButton.setEnabled(false);    break;   case R.id.btn_online_play:    new Thread(new Runnable() {     @Override     public void run() {      player.playUrl(pathText.getText().toString());     }    }).start();    break;   }  }  /*   * 由于用户的输入事件(点击button, 触摸屏幕....)是由主线程负责处理的，如果主线程处于工作状态，   * 此时用户产生的输入事件如果没能在5秒内得到处理，系统就会报“应用无响应”错误。   * 所以在主线程里不能执行一件比较耗时的工作，否则会因主线程阻塞而无法处理用户的输入事件，   * 导致“应用无响应”错误的出现。耗时的工作应该在子线程里执行。   */  private DownloadTask task;  private void exit() {   if (task != null)    task.exit();  }  private void download(String path, File savDir) {   task = new DownloadTask(path, savDir);   new Thread(task).start();  }  /**   *    * UI控件画面的重绘(更新)是由主线程负责处理的，如果在子线程中更新UI控件的值，更新后的值不会重绘到屏幕上   * 一定要在主线程里更新UI控件的值，这样才能在屏幕上显示出来，不能在子线程中更新UI控件的值   *    */  private final class DownloadTask implements Runnable {   private String path;   private File saveDir;   private FileDownloader loader;   public DownloadTask(String path, File saveDir) {    this.path = path;    this.saveDir = saveDir;   }   /**    * 退出下载    */   public void exit() {    if (loader != null)     loader.exit();   }   DownloadProgressListener downloadProgressListener = new DownloadProgressListener() {    @Override    public void onDownloadSize(int size) {     Message msg = new Message();     msg.what = PROCESSING;     msg.getData().putInt("size", size);     handler.sendMessage(msg);    }   };   public void run() {    try {     // 实例化一个文件下载器     loader = new FileDownloader(getApplicationContext(), path,       saveDir, 3);     // 设置进度条最大值     progressBar.setMax(loader.getFileSize());     loader.download(downloadProgressListener);    } catch (Exception e) {     e.printStackTrace();     handler.sendMessage(handler.obtainMessage(FAILURE)); // 发送一条空消息对象    }   }  } } // 进度改变 class SeekBarChangeEvent implements OnSeekBarChangeListener {  int progress;  @Override  public void onProgressChanged(SeekBar seekBar, int progress,    boolean fromUser) {   // 原本是(progress/seekBar.getMax())*player.mediaPlayer.getDuration()   this.progress = progress * player.mediaPlayer.getDuration()     / seekBar.getMax();  }  @Override  public void onStartTrackingTouch(SeekBar seekBar) {  }  @Override  public void onStopTrackingTouch(SeekBar seekBar) {   // seekTo()的参数是相对与影片时间的数字，而不是与seekBar.getMax()相对的数字   player.mediaPlayer.seekTo(progress);  } } @Override protected void onDestroy() {  super.onDestroy();  if (player != null) {   player.stop();   player = null;  } }}

           

给我老师的人工智能教程打call！http://blog.csdn.net/jiangjunshow