本文实例讲述了Android实现使用流媒体播放远程mp3文件的方法。分享给大家供大家参考，具体如下：
package com.shadow.util; import java.io.BufferedInputStream; import java.io.BufferedOutputStream; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.net.URL; import java.net.URLConnection; import java.util.ArrayList; import java.util.List; import com.shadow.service.AudioPlayService.LocalBinder; import android.app.Service; import android.content.Context; import android.content.Intent; import android.media.MediaPlayer; import android.os.Binder; import android.os.Handler; import android.os.IBinder; import android.util.Log; import android.widget.Button; import android.widget.ImageButton; import android.widget.ProgressBar; import android.widget.TextView; import android.widget.Toast; /** * MediaPlayer does not yet support streaming from external URLs so this class provides a pseudo-streaming function * by downloading the content incrementally & playing as soon as we get enough audio in our temporary storage. */ public class StreamingMediaPlayer extends Service{ private static final int INTIAL_KB_BUFFER = 96*10/8;//assume 96kbps*10secs/8bits per byte private TextView textStreamed; private ImageButton playButton; private ProgressBar progressBar; // Track for display by progressBar private long mediaLengthInKb, mediaLengthInSeconds; private int totalKbRead = 0; // Create Handler to call View updates on the main UI thread. private final Handler handler = new Handler(); private MediaPlayer mediaPlayer; private File downloadingMediaFile; private boolean isInterrupted; private Context context; private int counter = 0; private static Runnable r; private static Thread playerThread; private LocalBinder localBinder = new LocalBinder(); private MediaPlayer player; private boolean isPause = false; //播放器是否处于暂停状态 private boolean isSame = false; //所点播歌曲是否是当前播放歌曲 private Integer position = -1; //设置播放标记 private List<String> music_name; //歌曲列表 private List<String> music_path; public StreamingMediaPlayer(Context context,TextView textStreamed, ImageButton playButton, Button streamButton,ProgressBar progressBar) { this.context = context; this.textStreamed = textStreamed; this.playButton = playButton; this.progressBar = progressBar; } /** * Progressivly download the media to a temporary location and update the MediaPlayer as new content becomes available. */ public void startStreaming(final String mediaUrl, long mediaLengthInKb, long mediaLengthInSeconds) throws IOException { this.mediaLengthInKb = mediaLengthInKb; this.mediaLengthInSeconds = mediaLengthInSeconds; r = new Runnable() { public void run() { try { Log.i("downloadAudioIncrement", "downloadAudioIncrement"); downloadAudioIncrement(mediaUrl); } catch (IOException e) { Log.e(getClass().getName(), "Unable to initialize the MediaPlayer for fileUrl=" + mediaUrl, e); return; } } }; playerThread = new Thread(r); playerThread.start(); //new Thread(r).start(); } /** * Download the url stream to a temporary location and then call the setDataSource * for that local file */ public void downloadAudioIncrement(String mediaUrl) throws IOException { URLConnection cn = new URL(mediaUrl).openConnection(); cn.addRequestProperty("User-Agent","NSPlayer/10.0.0.4072 WMFSDK/10.0"); cn.connect(); InputStream stream = cn.getInputStream(); if (stream == null) { Log.e(getClass().getName(), "Unable to create InputStream for mediaUrl:" + mediaUrl); } downloadingMediaFile = new File(context.getCacheDir(),"downloadingMedia.dat"); // Just in case a prior deletion failed because our code crashed or something, we also delete any previously // downloaded file to ensure we start fresh. If you use this code, always delete // no longer used downloads else you'll quickly fill up your hard disk memory. Of course, you can also // store any previously downloaded file in a separate data cache for instant replay if you wanted as well. if (downloadingMediaFile.exists()) { downloadingMediaFile.delete(); } FileOutputStream out = new FileOutputStream(downloadingMediaFile); byte buf[] = new byte[16384]; int totalBytesRead = 0, incrementalBytesRead = 0; do { int numread = stream.read(buf); if (numread <= 0) break; out.write(buf, 0, numread); totalBytesRead += numread; incrementalBytesRead += numread; totalKbRead = totalBytesRead/1000; testMediaBuffer(); fireDataLoadUpdate(); } while (validateNotInterrupted()); stream.close(); if (validateNotInterrupted()) { fireDataFullyLoaded(); } } private boolean validateNotInterrupted() { if (isInterrupted) { if (mediaPlayer != null) { mediaPlayer.pause(); //mediaPlayer.release(); } return false; } else { return true; } } /** * Test whether we need to transfer buffered data to the MediaPlayer. * Interacting with MediaPlayer on non-main UI thread can causes crashes to so perform this using a Handler. */ private void testMediaBuffer() { Runnable updater = new Runnable() { public void run() { if (mediaPlayer == null) { // Only create the MediaPlayer once we have the minimum buffered data if ( totalKbRead >= INTIAL_KB_BUFFER) { try { startMediaPlayer(); } catch (Exception e) { Log.e(getClass().getName(), "Error copying buffered conent.", e); } } } else if ( mediaPlayer.getDuration() - mediaPlayer.getCurrentPosition() <= 1000 ){ // NOTE: The media player has stopped at the end so transfer any existing buffered data // We test for < 1second of data because the media player can stop when there is still // a few milliseconds of data left to play transferBufferToMediaPlayer(); } } }; handler.post(updater); } private void startMediaPlayer() { try { File bufferedFile = new File(context.getCacheDir(),"playingMedia" + (counter++) + ".dat"); // We double buffer the data to avoid potential read/write errors that could happen if the // download thread attempted to write at the same time the MediaPlayer was trying to read. // For example, we can't guarantee that the MediaPlayer won't open a file for playing and leave it locked while // the media is playing. This would permanently deadlock the file download. To avoid such a deadloack, // we move the currently loaded data to a temporary buffer file that we start playing while the remaining // data downloads. moveFile(downloadingMediaFile,bufferedFile); Log.e(getClass().getName(),"Buffered File path: " + bufferedFile.getAbsolutePath()); Log.e(getClass().getName(),"Buffered File length: " + bufferedFile.length()+""); mediaPlayer = createMediaPlayer(bufferedFile); // We have pre-loaded enough content and started the MediaPlayer so update the buttons & progress meters. mediaPlayer.start(); startPlayProgressUpdater(); playButton.setEnabled(true); } catch (IOException e) { Log.e(getClass().getName(), "Error initializing the MediaPlayer.", e); return; } } public void pausePlayer(){ try { getMediaPlayer().pause(); } catch (Exception e) { e.printStackTrace(); } } public void startPlayer(){ getMediaPlayer().start(); } public void stopPlayer(){ getMediaPlayer().stop(); } /** * 根据文件创建一个mediaplayer对象 */ private MediaPlayer createMediaPlayer(File mediaFile) throws IOException { MediaPlayer mPlayer = new MediaPlayer(); mPlayer.setOnErrorListener( new MediaPlayer.OnErrorListener() { public boolean onError(MediaPlayer mp, int what, int extra) { Log.e(getClass().getName(), "Error in MediaPlayer: (" + what +") with extra (" +extra +")" ); return false; } }); // It appears that for security/permission reasons, it is better to pass a FileDescriptor rather than a direct path to the File. // Also I have seen errors such as "PVMFErrNotSupported" and "Prepare failed.: status=0x1" if a file path String is passed to // setDataSource(). So unless otherwise noted, we use a FileDescriptor here. FileInputStream fis = new FileInputStream(mediaFile); mPlayer.setDataSource(fis.getFD()); mPlayer.prepare(); return mPlayer; } package com.shadow.util; import java.io.BufferedInputStream; import java.io.BufferedOutputStream; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.net.URL; import java.net.URLConnection; import java.util.ArrayList; import java.util.List; import com.shadow.service.AudioPlayService.LocalBinder; import android.app.Service; import android.content.Context; import android.content.Intent; import android.media.MediaPlayer; import android.os.Binder; import android.os.Handler; import android.os.IBinder; import android.util.Log; import android.widget.Button; import android.widget.ImageButton; import android.widget.ProgressBar; import android.widget.TextView; import android.widget.Toast; /** * MediaPlayer does not yet support streaming from external URLs so this class provides a pseudo-streaming function * by downloading the content incrementally & playing as soon as we get enough audio in our temporary storage. */ public class StreamingMediaPlayer extends Service{ private static final int INTIAL_KB_BUFFER = 96*10/8;//assume 96kbps*10secs/8bits per byte private TextView textStreamed; private ImageButton playButton; private ProgressBar progressBar; // Track for display by progressBar private long mediaLengthInKb, mediaLengthInSeconds; private int totalKbRead = 0; // Create Handler to call View updates on the main UI thread. private final Handler handler = new Handler(); private MediaPlayer mediaPlayer; private File downloadingMediaFile; private boolean isInterrupted; private Context context; private int counter = 0; private static Runnable r; private static Thread playerThread; private LocalBinder localBinder = new LocalBinder(); private MediaPlayer player; private boolean isPause = false; //播放器是否处于暂停状态 private boolean isSame = false; //所点播歌曲是否是当前播放歌曲 private Integer position = -1; //设置播放标记 private List<String> music_name; //歌曲列表 private List<String> music_path; public StreamingMediaPlayer(Context context,TextView textStreamed, ImageButton playButton, Button streamButton,ProgressBar progressBar) { this.context = context; this.textStreamed = textStreamed; this.playButton = playButton; this.progressBar = progressBar; } /** * Progressivly download the media to a temporary location and update the MediaPlayer as new content becomes available. */ public void startStreaming(final String mediaUrl, long mediaLengthInKb, long mediaLengthInSeconds) throws IOException { this.mediaLengthInKb = mediaLengthInKb; this.mediaLengthInSeconds = mediaLengthInSeconds; r = new Runnable() { public void run() { try { Log.i("downloadAudioIncrement", "downloadAudioIncrement"); downloadAudioIncrement(mediaUrl); } catch (IOException e) { Log.e(getClass().getName(), "Unable to initialize the MediaPlayer for fileUrl=" + mediaUrl, e); return; } } }; playerThread = new Thread(r); playerThread.start(); //new Thread(r).start(); } /** * Download the url stream to a temporary location and then call the setDataSource * for that local file */ public void downloadAudioIncrement(String mediaUrl) throws IOException { URLConnection cn = new URL(mediaUrl).openConnection(); cn.addRequestProperty("User-Agent","NSPlayer/10.0.0.4072 WMFSDK/10.0"); cn.connect(); InputStream stream = cn.getInputStream(); if (stream == null) { Log.e(getClass().getName(), "Unable to create InputStream for mediaUrl:" + mediaUrl); } downloadingMediaFile = new File(context.getCacheDir(),"downloadingMedia.dat"); // Just in case a prior deletion failed because our code crashed or something, we also delete any previously // downloaded file to ensure we start fresh. If you use this code, always delete // no longer used downloads else you'll quickly fill up your hard disk memory. Of course, you can also // store any previously downloaded file in a separate data cache for instant replay if you wanted as well. if (downloadingMediaFile.exists()) { downloadingMediaFile.delete(); } FileOutputStream out = new FileOutputStream(downloadingMediaFile); byte buf[] = new byte[16384]; int totalBytesRead = 0, incrementalBytesRead = 0; do { int numread = stream.read(buf); if (numread <= 0) break; out.write(buf, 0, numread); totalBytesRead += numread; incrementalBytesRead += numread; totalKbRead = totalBytesRead/1000; testMediaBuffer(); fireDataLoadUpdate(); } while (validateNotInterrupted()); stream.close(); if (validateNotInterrupted()) { fireDataFullyLoaded(); } } private boolean validateNotInterrupted() { if (isInterrupted) { if (mediaPlayer != null) { mediaPlayer.pause(); //mediaPlayer.release(); } return false; } else { return true; } } /** * Test whether we need to transfer buffered data to the MediaPlayer. * Interacting with MediaPlayer on non-main UI thread can causes crashes to so perform this using a Handler. */ private void testMediaBuffer() { Runnable updater = new Runnable() { public void run() { if (mediaPlayer == null) { // Only create the MediaPlayer once we have the minimum buffered data if ( totalKbRead >= INTIAL_KB_BUFFER) { try { startMediaPlayer(); } catch (Exception e) { Log.e(getClass().getName(), "Error copying buffered conent.", e); } } } else if ( mediaPlayer.getDuration() - mediaPlayer.getCurrentPosition() <= 1000 ){ // NOTE: The media player has stopped at the end so transfer any existing buffered data // We test for < 1second of data because the media player can stop when there is still // a few milliseconds of data left to play transferBufferToMediaPlayer(); } } }; handler.post(updater); } private void startMediaPlayer() { try { File bufferedFile = new File(context.getCacheDir(),"playingMedia" + (counter++) + ".dat"); // We double buffer the data to avoid potential read/write errors that could happen if the // download thread attempted to write at the same time the MediaPlayer was trying to read. // For example, we can't guarantee that the MediaPlayer won't open a file for playing and leave it locked while // the media is playing. This would permanently deadlock the file download. To avoid such a deadloack, // we move the currently loaded data to a temporary buffer file that we start playing while the remaining // data downloads. moveFile(downloadingMediaFile,bufferedFile); Log.e(getClass().getName(),"Buffered File path: " + bufferedFile.getAbsolutePath()); Log.e(getClass().getName(),"Buffered File length: " + bufferedFile.length()+""); mediaPlayer = createMediaPlayer(bufferedFile); // We have pre-loaded enough content and started the MediaPlayer so update the buttons & progress meters. mediaPlayer.start(); startPlayProgressUpdater(); playButton.setEnabled(true); } catch (IOException e) { Log.e(getClass().getName(), "Error initializing the MediaPlayer.", e); return; } } public void pausePlayer(){ try { getMediaPlayer().pause(); } catch (Exception e) { e.printStackTrace(); } } public void startPlayer(){ getMediaPlayer().start(); } public void stopPlayer(){ getMediaPlayer().stop(); } /** * 根据文件创建一个mediaplayer对象 */ private MediaPlayer createMediaPlayer(File mediaFile) throws IOException { MediaPlayer mPlayer = new MediaPlayer(); mPlayer.setOnErrorListener( new MediaPlayer.OnErrorListener() { public boolean onError(MediaPlayer mp, int what, int extra) { Log.e(getClass().getName(), "Error in MediaPlayer: (" + what +") with extra (" +extra +")" ); return false; } }); // It appears that for security/permission reasons, it is better to pass a FileDescriptor rather than a direct path to the File. // Also I have seen errors such as "PVMFErrNotSupported" and "Prepare failed.: status=0x1" if a file path String is passed to // setDataSource(). So unless otherwise noted, we use a FileDescriptor here. FileInputStream fis = new FileInputStream(mediaFile); mPlayer.setDataSource(fis.getFD()); mPlayer.prepare(); return mPlayer; } /** * 把缓存转化成mediaplay对象 * Transfer buffered data to the MediaPlayer. * NOTE: Interacting with a MediaPlayer on a non-main UI thread can cause thread-lock and crashes so * this method should always be called using a Handler. */ private void transferBufferToMediaPlayer() { try { // First determine if we need to restart the player after transferring data...e.g. perhaps the user pressed pause boolean wasPlaying = mediaPlayer.isPlaying(); int curPosition = mediaPlayer.getCurrentPosition(); // Copy the currently downloaded content to a new buffered File. Store the old File for deleting later. File oldBufferedFile = new File(context.getCacheDir(),"playingMedia" + counter + ".dat"); File bufferedFile = new File(context.getCacheDir(),"playingMedia" + (counter++) + ".dat"); // This may be the last buffered File so ask that it be delete on exit. If it's already deleted, then this won't mean anything. If you want to // keep and track fully downloaded files for later use, write caching code and please send me a copy. bufferedFile.deleteOnExit(); moveFile(downloadingMediaFile,bufferedFile); // Pause the current player now as we are about to create and start a new one. So far (Android v1.5), // this always happens so quickly that the user never realized we've stopped the player and started a new one mediaPlayer.pause(); // Create a new MediaPlayer rather than try to re-prepare the prior one. mediaPlayer = createMediaPlayer(bufferedFile); mediaPlayer.seekTo(curPosition); // Restart if at end of prior buffered content or mediaPlayer was previously playing. // NOTE: We test for < 1second of data because the media player can stop when there is still // a few milliseconds of data left to play boolean atEndOfFile = mediaPlayer.getDuration() - mediaPlayer.getCurrentPosition() <= 1000; if (wasPlaying || atEndOfFile){ mediaPlayer.start(); } // Lastly delete the previously playing buffered File as it's no longer needed. oldBufferedFile.delete(); }catch (Exception e) { Log.e(getClass().getName(), "Error updating to newly loaded content.", e); } } private void fireDataLoadUpdate() { Runnable updater = new Runnable() { public void run() { //textStreamed.setText((totalKbRead + " Kb read")); float loadProgress = ((float)totalKbRead/(float)mediaLengthInKb); //progressBar.setSecondaryProgress((int)(loadProgress*100)); } }; handler.post(updater); } private void fireDataFullyLoaded() { Runnable updater = new Runnable() { public void run() { transferBufferToMediaPlayer(); // Delete the downloaded File as it's now been transferred to the currently playing buffer file. downloadingMediaFile.delete(); //textStreamed.setText(("Audio full loaded: " + totalKbRead + " Kb read")); } }; handler.post(updater); } //TODO 这个方法应该可以控制歌曲的播放 public MediaPlayer getMediaPlayer() { return mediaPlayer; } public void startPlayProgressUpdater() { float progress = (((float)mediaPlayer.getCurrentPosition()/1000)/mediaLengthInSeconds); progressBar.setProgress((int)(progress*100)); if (mediaPlayer.isPlaying()) { Runnable notification = new Runnable() { public void run() { startPlayProgressUpdater(); } }; handler.postDelayed(notification,1000); } } public void interrupt() { playButton.setEnabled(false); isInterrupted = true; validateNotInterrupted(); } /** * Move the file in oldLocation to newLocation. */ public void moveFile(File oldLocation, File newLocation) throws IOException { if ( oldLocation.exists( )) { BufferedInputStream reader = new BufferedInputStream( new FileInputStream(oldLocation) ); BufferedOutputStream writer = new BufferedOutputStream( new FileOutputStream(newLocation, false)); try { byte[] buff = new byte[8192]; int numChars; while ( (numChars = reader.read( buff, 0, buff.length ) ) != -1) { writer.write( buff, 0, numChars ); } } catch( IOException ex ) { throw new IOException("IOException when transferring " + oldLocation.getPath() + " to " + newLocation.getPath()); } finally { try { if ( reader != null ){ writer.close(); reader.close(); } } catch( IOException ex ){ Log.e(getClass().getName(),"Error closing files when transferring " + oldLocation.getPath() + " to " + newLocation.getPath() ); } } } else { throw new IOException("Old location does not exist when transferring " + oldLocation.getPath() + " to " + newLocation.getPath() ); } } /** * 獲取service中的播放器对象 * @return 播放器对象 */ public MediaPlayer getPlayer() { return this.player; } @Override public void onStart(Intent intent, int startId) { super.onStart(intent, startId); /** * 1.现在需要的就是做从PlayActivity里获取歌曲列表，和歌曲路径，歌曲手名 * 并存放到各个集合里 * 2.之后就是对对这些数组进行处理 */ music_name = new ArrayList<String>(); music_path = new ArrayList<String>(); String info = intent.getStringExtra("info"); //songPath = intent.getStringExtra("songPath"); Toast.makeText(getApplicationContext(), "歌曲播放异常", Toast.LENGTH_SHORT).show(); player = new MediaPlayer(); try { playMusic(info); } catch (Exception e) { Toast.makeText(getApplicationContext(), "歌曲播放异常", Toast.LENGTH_SHORT).show(); e.printStackTrace(); } } //播放音乐 private void playMusic(String info) throws Exception { if ("play".equals(info)) { if (isPause) {// 暂停后，继续播放 player.start(); isPause = false; } else if (isSame) {// 如果现在播放和与所点播歌曲时同一首，继续播放所选歌曲 player.start(); } else {// 点播某一首歌曲 play(); } } else if ("pause".equals(info)) { player.pause();// 暂停 isPause = true; } else if ("before".equals(info)) { playBefore();// 播放上一首 } else if ("after".equals(info)) { playAfter();// 播放下一首 } } private void play() throws Exception { //TODO 获取歌曲路径 try { Log.i("playtest", "playtest"); // myApp.setPlaying_position(position); //设置歌曲 当前的播放标记 player.reset(); //player.setDataSource(songPath); player.start(); //musicName = music_name.get(position); } catch (Exception e) { e.printStackTrace(); } } private void playBefore() throws Exception { if (position == 0) { position = music_name.size() - 1; } else { position--; } play(); } private void playAfter() throws Exception { if (position == 0) { position = music_name.size() + 1; } else { position++; } play(); } public class LocalBinder extends Binder { public StreamingMediaPlayer getService() { return StreamingMediaPlayer.this; } } @Override public void onDestroy() { super.onDestroy(); } @Override public boolean onUnbind(Intent intent) { return super.onUnbind(intent); } @Override public IBinder onBind(Intent intent) { return localBinder; } }
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