我有一个动作活动，附有一个片段 和一个服务类，它是从网址流式传输音乐。 下面我粘贴一些代码供参考
TopTenFragment.java
public class ToptenFragment extends Fragment {
private ListView TrackList;
private CustomAdapter songadapter;
private ArrayList<Song> songList;
int currentduration;
ArrayList<Integer> buttonposiotion = new ArrayList<Integer>();
private int curBtnIndex = -1;
// private boolean paused = false;
private int lastpos;
// service
private MyService musicSrv;
private Intent playIntent;
// binding
private boolean musicBound = false;
// activity and playback pause flags
private boolean paused = false, playbackPaused = false;
int i = 0;
int start = 0;
String urlindex;
public ImageView imageView;
private ProgressBar bar;
private WeakReference<Activity> mainActivityWeakRef;
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
System.out.println("onActivityCreated");
mainActivityWeakRef = new WeakReference<Activity>(
(Activity) getActivity());
if (mainActivityWeakRef.get() != null
&& !mainActivityWeakRef.get().isFinishing()) {
getData();
}
SharedPreferences onStopPf = getActivity().getSharedPreferences(
"On Stop", 0);
Editor stEditor = onStopPf.edit();
curBtnIndex = onStopPf.getInt("btnIndex", -1);
stEditor.commit();
System.out.println("curt index from top -> " + curBtnIndex);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
System.out.println("onCreateView");
View v = inflater.inflate(R.layout.main, container, false);
initLayout(v);
return v;
}
private void initLayout(View v) {
TrackList = (ListView) v.findViewById(R.id.songList);
// get image for ad
imageView = (ImageView) v.findViewById(R.id.radio_adview);
bar = (ProgressBar) v.findViewById(R.id.load);
}
public void getData() {
Map<String, String> map = new HashMap<String, String>();
map.put("url", getActivity().getString(R.string.get_song));
new GetData(map);
}
public class CustomAdapter extends BaseAdapter {
private ArrayList<Song> songListLocal;
public Activity context;
// Song s;
public LayoutInflater inflater;
public CustomAdapter(Activity context, ArrayList<Song> arr_calllog_name) {
super();
this.context = context;
this.songListLocal = arr_calllog_name;
inflater = (LayoutInflater) getActivity().getSystemService(
Context.LAYOUT_INFLATER_SERVICE);
}
@Override
public int getCount() {
return songListLocal.size();
}
@Override
public Object getItem(int arg0) {
return arg0;
}
@Override
public long getItemId(int arg0) {
return arg0;
}
@Override
public View getView(final int position, View convertView,
ViewGroup parent) {
ImageView song_thumb;
TextView txtName, songNumTxt;
final Button playbutton;
final Button stopbutton;
final Button pausebutton;
View view = convertView;
final Song s = songListLocal.get(position);
view = inflater.inflate(R.layout.list_item, null);
song_thumb = (ImageView) view.findViewById(R.id.songthumb);
txtName = (TextView) view.findViewById(R.id.songname);
songNumTxt = (TextView) view.findViewById(R.id.songNum);
playbutton = (Button) view.findViewById(R.id.playbutton);
stopbutton = (Button) view.findViewById(R.id.stopbutton);
pausebutton = (Button) view.findViewById(R.id.pausebutton);
Picasso.with(getActivity()).load(s.getSong_icon()).into(song_thumb);
txtName.setText(s.getName());
songNumTxt.setText(String.valueOf(s.getSongNum()));
playbutton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
curBtnIndex = position;
songPicked(position);
setlistview();
playbutton.setVisibility(View.INVISIBLE);
pausebutton.setVisibility(View.VISIBLE);
stopbutton.setVisibility(View.VISIBLE);
}
});
pausebutton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
//pause
}
});
stopbutton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v1) {
try {
paused = false;
playbutton.setVisibility(View.VISIBLE);
pausebutton.setVisibility(View.INVISIBLE);
stopbutton.setVisibility(View.INVISIBLE);
} catch (Exception e) {
System.out.println("exception in pause");
}
}
});
if (curBtnIndex == position) {
pausebutton.setVisibility(View.VISIBLE);
stopbutton.setVisibility(View.VISIBLE);
playbutton.setVisibility(View.INVISIBLE);
} else {
pausebutton.setVisibility(View.INVISIBLE);
stopbutton.setVisibility(View.INVISIBLE);
}
return view;
}
}
// user song select
public void songPicked(int pos) {
musicSrv.setSong(pos);
musicSrv.playSong();
if (playbackPaused) {
playbackPaused = false;
}
}
public void setlistview() {
TrackList.setAdapter(songadapter);
TrackList.setSelection(curBtnIndex);
}
private class GetData {
private final Map<String, String> map;
public GetData(Map<String, String> map2) {
this.map = map2;
new AsynRequest().execute(map.get("url"));
}
class AsynRequest extends AsyncTask<String, Void, String> {
@Override
protected void onPreExecute() {
}
@Override
protected String doInBackground(String... urls) {
map.remove("url");
HttpPost httppost = new HttpPost(urls[0]);
try {
HttpClient httpclient = new DefaultHttpClient();
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
for (String key : map.keySet()) {
System.out.println(key + " < === > " + map.get(key));
nameValuePairs.add(new BasicNameValuePair(key, map
.get(key)));
}
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs,
"UTF-8"));
HttpResponse response = httpclient.execute(httppost);
String responseBody = EntityUtils.toString(response
.getEntity());
return responseBody;
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(String result) {
// System.out.println("result of songs -> " + result);
bar.setVisibility(View.GONE);
if (result != null) {
try {
JSONObject jObject = new JSONObject(result);
String result1 = jObject.getString("result");
if (result1.equals("success")) {
JSONArray jArray = jObject.getJSONArray("songs");
songList = null;
songList = new ArrayList<Song>();
for (int i = 0; i < jArray.length(); i++) {
JSONObject j = jArray.getJSONObject(i);
Song s = new Song();
String song_icon_path = j
.getString("song_icon");
String name = j.getString("name");
String song_file_path = j.getString("song_url");
s.setSong_icon(song_icon_path);
s.setName(name);
s.setSong_url(song_file_path);
int n = i + 1;
s.setSongNum(n);
songList.add(s);
}
if (songList != null) {
System.out.println("song list size -> "
+ songList.size());
mainActivityWeakRef = new WeakReference<Activity>(
(Activity) getActivity());
if (mainActivityWeakRef.get() != null
&& !mainActivityWeakRef.get()
.isFinishing()) {
songadapter = new CustomAdapter(
getActivity(), songList);
TrackList.setAdapter(songadapter);
if (playIntent == null) {
playIntent = new Intent(getActivity(),
MyService.class);
musicBound = getActivity().bindService(
playIntent, musicConnection,
Context.BIND_AUTO_CREATE);
System.out.println("service bound -> "
+ musicBound);
getActivity().startService(playIntent);
}
}
} else {
System.out.println("song list null");
}
}
} catch (JSONException e) {
e.printStackTrace();
bar.setVisibility(View.GONE);
}
}
super.onPostExecute(result);
}
}
}
@Override
public void onDestroyView() {
System.out.println("onDestroyView()");
boolean s = isMyServiceRunning(MyService.class);
System.out.println("runnind ? " + s);
if (musicBound) {
musicBound = false;
getActivity().unbindService(musicConnection);
} else
System.out.println("not bound");
super.onDestroyView();
}
private boolean isMyServiceRunning(Class<?> serviceClass) {
ActivityManager manager = (ActivityManager) getActivity()
.getSystemService(Context.ACTIVITY_SERVICE);
for (RunningServiceInfo service : manager
.getRunningServices(Integer.MAX_VALUE)) {
if (serviceClass.getName().equals(service.service.getClassName())) {
return true;
}
}
return false;
}
// connect to the service
private ServiceConnection musicConnection = new ServiceConnection() {
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
MyBinder binder = (MyBinder) service;
// get service
musicSrv = binder.getService();
// pass list
musicSrv.setList(songList);
musicBound = true;
}
@Override
public void onServiceDisconnected(ComponentName name) {
musicBound = false;
}
};
MyService.java
public class MyService extends Service implements OnCompletionListener,
OnErrorListener, OnPreparedListener {
// media player
private MediaPlayer player;
// song list
private ArrayList<Song> songs;
// current position
private int songPosn;
// binder
private final IBinder musicBind = new MyBinder();
// title of current song
private String songTitle = "";
// notification id
private static final int NOTIFY_ID = 1;
@Override
public void onCreate() {
// create the service
super.onCreate();
// initialize position
songPosn = 0;
// create player
player = new MediaPlayer();
// initialize
initMusicPlayer();
}
public void initMusicPlayer() {
// set player properties
player.setWakeMode(getApplicationContext(),
PowerManager.PARTIAL_WAKE_LOCK);
player.setAudioStreamType(AudioManager.STREAM_MUSIC);
// set listeners
player.setOnPreparedListener(this);
player.setOnCompletionListener(this);
player.setOnErrorListener(this);
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
return START_STICKY;
}
// pass song list
public void setList(ArrayList<Song> theSongs) {
songs = theSongs;
}
// binder
public class MyBinder extends Binder {
MyService getService() {
return MyService.this;
}
}
// activity will bind to service
@Override
public IBinder onBind(Intent intent) {
return musicBind;
}
// release resources when unbind
@Override
public boolean onUnbind(Intent intent) {
player.stop();
player.release();
return false;
}
// play a song
public void playSong() {
// play
player.reset();
// get song
Song playSong = songs.get(songPosn);
// get title
songTitle = playSong.getName();
String trackUri = playSong.getSong_url();
System.out.println("track uri -> " + trackUri);
// set the data source
try {
player.setDataSource(trackUri);
} catch (Exception e) {
Log.e("MUSIC SERVICE", "Error setting data source", e);
}
player.prepareAsync();
}
// set the song
public void setSong(int songIndex) {
songPosn = songIndex;
}
@Override
public void onCompletion(MediaPlayer mp) {
// check if playback has reached the end of a track
if (player.getCurrentPosition() > 0) {
mp.reset();
}
}
@Override
public boolean onError(MediaPlayer mp, int what, int extra) {
Log.v("MUSIC PLAYER", "Playback Error");
mp.reset();
return false;
}
@Override
public void onPrepared(MediaPlayer mp) {
playMusic();
}
@Override
public void onDestroy() {
Log.e("MUSIC PLAYER", "onDestroy()");
stopForeground(true);
}
public void playMusic() {
player.start();
// notification
Intent notIntent = new Intent(this, MainActivity.class);
PendingIntent pendInt = PendingIntent.getActivity(this, 0, notIntent,
PendingIntent.FLAG_UPDATE_CURRENT);
Notification.Builder builder = new Notification.Builder(this);
builder.setContentIntent(pendInt).setSmallIcon(R.drawable.ic_launcher)
.setTicker(songTitle).setOngoing(true)
.setContentTitle("Playing").setContentText(songTitle);
Notification not = builder.build();
startForeground(NOTIFY_ID, not);
}
}
音乐播放效果很好，但是当我在设备上反印时它会停止音乐。 我的问题是，如果用户按下硬件后门按钮，我想继续在后台播放音乐。
任何帮助都会表示赞赏 感谢
答案 0 :(得分：1)
您正在解除onDestroyView中的服务绑定。当最后一个ServiceConnection未绑定时，onUnbind上会调用Service方法。您的onUnbind实施会停止播放。相反，您应该在前台通知中包含播放控件，并通过指向您的服务类的PendingIntent控制播放。