StreamingMediaPlayer .java MediaPlayer尚不支持从外部URL流式传输，因此该类提供了伪流功能 通过逐步下载内容＆amp;我们在临时存储中获得足够的音频后立即播放。
但代码报告错误......它没有播放视频，只是显示流进度
public class StreamingMediaPlayer {
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;//mediaplayer
private File downloadingMediaFile; //old location
private boolean isInterrupted;
private Context context;
private int counter = 0;
public StreamingMediaPlayer(Context context,TextView textStreamed, ImageButton playButton, Button streamButton,ProgressBar progressBar)
{
this.context = context;
this.textStreamed = textStreamed;
this.playButton = playButton;
this.progressBar = progressBar;
}
/**
* Progressively 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;
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();
}
/**
* 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.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_" + (counter++) + ".dat");
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");
moveFile(downloadingMediaFile,bufferedFile);
Log.e("Player",bufferedFile.length()+"");
Log.e("Player",bufferedFile.getAbsolutePath());
mediaPlayer = new MediaPlayer();
mediaPlayer.setDataSource(bufferedFile.getAbsolutePath());
mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
mediaPlayer.prepareAsync();
fireDataPreloadComplete();
} catch (IOException e) {
Log.e(getClass().getName(), "Error initializing the MediaPlaer.", e);
return;
}
}
/**
* 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 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();
mediaPlayer.pause();
File bufferedFile = new File(context.getCacheDir(),"playingMedia" + (counter++) + ".dat");
//FileUtils.copyFile(downloadingMediaFile,bufferedFile);
mediaPlayer = new MediaPlayer();
mediaPlayer.setDataSource(bufferedFile.getAbsolutePath());
//mediaPlayer.setAudioStreamType(AudioSystem.STREAM_MUSIC);
mediaPlayer.prepareAsync();
mediaPlayer.seekTo(curPosition);
// Restart if at end of prior beuffered 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();
}
}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((CharSequence) (totalKbRead + " Kb read"));
float loadProgress = ((float)totalKbRead/(float)mediaLengthInKb);
progressBar.setSecondaryProgress((int)(loadProgress*100));
}
};
handler.post(updater);
}
/**
* We have preloaded enough content and started the MediaPlayer so update the buttons & progress meters.
*/
private void fireDataPreloadComplete() {
Runnable updater = new Runnable() {
public void run() {
mediaPlayer.start();
startPlayProgressUpdater();
playButton.setEnabled(true);
//streamButton.setEnabled(false);
}
};
handler.post(updater);
}
private void fireDataFullyLoaded() {
Runnable updater = new Runnable() {
public void run() {
transferBufferToMediaPlayer();
textStreamed.setText((CharSequence) ("Audio full loaded: " + totalKbRead + " Kb read"));
}
};
handler.post(updater);
}
public MediaPlayer getMediaPlayer() {
return mediaPlayer;
}
public void startPlayProgressUpdater() {
float progress = (((float)mediaPlayer.getCurrentPosition()/1000)/(float)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();
}
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() );
}
}
}
//java file
/*main activity*/
/* tutorial 3*/
package com.example.tutorial;
import java.io.IOException;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageButton;
import android.widget.MediaController;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.VideoView;
public class Tutorial3 extends Activity {
//VideoView videoView;
private Button streamButton;
private ImageButton playButton;
private TextView textStreamed;
private boolean isPlaying;
private StreamingMediaPlayer audioStreamer;
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.tutorial3);
initControls();
}
private void initControls() {
textStreamed = (TextView) findViewById(R.id.text_kb_streamed);
streamButton = (Button) findViewById(R.id.button_stream);
//videoView = (VideoView) findViewById(R.id.VideoView);
streamButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
startStreamingAudio();
}});
playButton = (ImageButton) findViewById(R.id.button_play);
playButton.setEnabled(false);
playButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
if (audioStreamer.getMediaPlayer().isPlaying()) {
audioStreamer.getMediaPlayer().pause();
playButton.setImageResource(R.drawable.button_play);
} else {
audioStreamer.getMediaPlayer().start();
audioStreamer.startPlayProgressUpdater();
playButton.setImageResource(R.drawable.button_pause);
}
isPlaying = !isPlaying;
}});
}
private void startStreamingAudio() {
try {
final ProgressBar progressBar = (ProgressBar) findViewById(R.id.progress_bar);
if ( audioStreamer != null) {
audioStreamer.interrupt();
}
audioStreamer = new StreamingMediaPlayer(this,textStreamed, playButton, streamButton,progressBar);
audioStreamer.startStreaming("http://www.boisestatefootball.com/sites/default/files/videos/original/01%20-%20coach%20pete%20bio_4.mp4",1677, 214);
//streamButton.setEnabled(false);
} catch (IOException e) {
Log.e(getClass().getName(), "Error starting to stream audio.", e);
}
}
}
//XML file
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
android:padding="10px" >
<TextView
android:id="@+id/text_kb_streamed"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Streaming .mp3 Audio Tutorial"
android:textStyle="bold" />
<Button
android:id="@+id/button_stream"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="10px"
android:text="Start Streaming" />
<ProgressBar
android:id="@+id/progress_bar"
style="?android:attr/progressBarStyleHorizontal"
android:layout_width="200px"
android:layout_height="wrap_content" />
<ImageButton
android:id="@+id/button_play"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="5px"
android:src="@drawable/button_pause" />
</LinearLayout>
以上代码报告了一些未知错误，如错误（-38,0）