音乐播放器 边下载边播music(程序源码).rar

package com.sharpandroid.music; 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 android.content.Context; import android.media.AudioManager; import android.media.MediaPlayer; import android.os.Handler; import android.os.Message; import android.util.Log; import android.widget.Button; import android.widget.ImageButton; import android.widget.SeekBar; import android.widget.TextView; public class StreamingMediaPlayer { private static final int INTIAL_KB_BUFFER = 96*10/8;//assume 96kbps*10secs/8bits per byte private ImageButton playButton; private SeekBar progressBar; private TextView playTime; private long mediaLengthInKb, mediaLengthInSeconds; private int totalKbRead = 0; //用于更新主界面 private final Handler handler = new Handler() { @Override public void handleMessage(Message msg) { super.handleMessage(msg); } }; private MediaPlayer mediaPlayer; private File downloadingMediaFile; private boolean isInterrupted; private Context context; private int counter = 0; public StreamingMediaPlayer(Context context, ImageButton playButton, Button streamButton, SeekBar progressBar,TextView playTime) { this.context = context; this.playButton = playButton; this.playTime=playTime; //播放的进度时刻 this.progressBar = progressBar; } /** * 开启一个线程，下载数据 */ public void startStreaming(final String mediaUrl, long mediaLengthInKb, long mediaLengthInSeconds) throws IOException { this.mediaLengthInKb = mediaLengthInKb; this.mediaLengthInSeconds = mediaLengthInSeconds; Runnable r = new Runnable() { public void run() { try { downloadAudioIncrement(mediaUrl); } catch (IOException e) { Log.e(getClass().getName(), "Unable to initialize the MediaPlayer for fileUrl=" + mediaUrl, e); return; } } }; new Thread(r).start(); } //根据获得的URL地址下载数据 public void downloadAudioIncrement(String mediaUrl) throws IOException { URLConnection cn = new URL(mediaUrl).openConnection(); 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"); if (downloadingMediaFile.exists()) { downloadingMediaFile.delete(); //如果下载完成则删除 } 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; //totalKbRead表示已经下载的文件大小 testMediaBuffer(); fireDataLoadUpdate(); } while (validateNotInterrupted()); stream.close(); if (validateNotInterrupted()) { fireDataFullyLoaded(); } } private boolean validateNotInterrupted() { if (isInterrupted) { if (mediaPlayer != null) { mediaPlayer.pause(); } return false; } else { return true; } } //测试缓冲的文件大小是否大于INTIAL_KB_BUFFER，如果大于的话就播放 private void testMediaBuffer() { Runnable updater = new Runnable() { public void run() { if (mediaPlayer == null) { 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 ){ transferBufferToMediaPlayer(); } } }; handler.post(updater); } private void startMediaPlayer() { try { File bufferedFile = new File(context.getCacheDir(),"playingMedia" + (counter++) + ".dat"); moveFile(downloadingMediaFile,bufferedFile); Log.e(getClass().getName(),"Buffered File path: " + bufferedFile.getAbsolutePath()); Log.e(getClass().getName(),"Buffered File length: " + bufferedFile.length()+""); mediaPlayer = createMediaPlayer(bufferedFile); mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC); mediaPlayer.start(); startPlayProgressUpdater(); playButton.setEnabled(true); } catch (IOException e) { Log.e(getClass().getName(), "Error initializing the MediaPlayer.", e); } } 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; } }); FileInputStream fis = new FileInputStream(mediaFile); mPlayer.setDataSource(fis.getFD());//此方法返回与流相关联的文件说明符。 mPlayer.prepare(); return mPlayer; } private void transferBufferToMediaPlayer() { try { boolean wasPlaying = mediaPlayer.isPlaying(); int curPosition = mediaPlayer.getCurrentPosition(); File oldBufferedFile = new File(context.getCacheDir(),"playingMedia" + counter + ".dat"); File bufferedFile = new File(context.getCacheDir(),"playingMedia" + (counter++) + ".dat"); bufferedFile.deleteOnExit(); moveFile(downloadingMediaFile,bufferedFile); mediaPlayer.pause(); mediaPlayer = createMediaPlayer(bufferedFile); mediaPlayer.seekTo(curPosition); boolean atEndOfFile = mediaPlayer.getDuration() - mediaPlayer.getCurrentPosition() <= 1000; if (wasPlaying || atEndOfFile){ mediaPlayer.start(); } 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")); 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(); downloadingMediaFile.delete(); } }; handler.post(updater); } public MediaPlayer getMediaPlayer() { return mediaPlayer; } public void startPlayProgressUpdater() { float progress = (((float)mediaPlayer.getCurrentPosition()/1000)/mediaLengthInSeconds); progressBar.setProgress((int)(progress*100)); int pos=mediaPlayer.getCurrentPosition(); int min = (pos/1000)/60; int sec = (pos/1000)%60; if(sec<10) playTime.setText(""+min+":0"+sec);//把音乐播放的进度，转换成时间 else playTime.setText(""+min+":"+sec); if (mediaPlayer.isPlaying()) { Runnable notification = new Runnable() { public void run() { startPlayProgressUpdater(); } };