背景音乐播放器

Question

我正在制作音乐应用程序，在后台播放音乐时遇到问题。当然，它正常工作，但当应用程序处于非活动状态时，它就会停止。我用尽了一切办法。我不知道为什么它不适合我使用我应该使用的服务。

此处代码：

玩家碎片：

public class PlayerFragment extends Fragment {
private FirebaseStorage storage;
private ImageButton main_btn, next_btn, back_btn, fav_btn, settings_btn;
private Uri localSong;
private   Intent myService;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view=  inflater.inflate(R.layout.fragment_player, container, false);
storage = FirebaseStorage.getInstance();
main_btn=  view.findViewById(R.id.player_main_btn);
next_btn=  view.findViewById(R.id.player_next_btn);
back_btn=  view.findViewById(R.id.player_back_btn);
fav_btn = view.findViewById(R.id.player_song_fav_btn);
settings_btn = view.findViewById(R.id.player_song_options_btn);

storage.getReference().child("songs/ni_bien_ni_mal.mp3").getDownloadUrl().addOnSuccessListener(new OnSuccessListener<Uri>() {
@Override
public void onSuccess(Uri uri) {
localSong=uri;
}
});
MainActivity mainActivity = (MainActivity) getActivity();
myService = new Intent(getActivity(), BackgroundSoundService.class);

main_btn.setOnClickListener(v -> {
if( main_btn.getDrawable().getConstantState().equals( main_btn.getContext().getDrawable(R.drawable.ic_play).getConstantState()))
{
new Thread(new Runnable() {
@Override
public void run() {
myService.putExtra("uri",localSong.toString() );
mainActivity.startService(myService);
}
}).start();
main_btn.setImageResource(R.drawable.ic_pause);
}
else
{
new Thread(new Runnable() {
@Override
public void run() {
//  mainActivity.stopService(myService);
main_btn.setImageResource(R.drawable.ic_play);
}
}).start();
}

});
fav_btn.setOnClickListener(v->{
if( fav_btn.getDrawable().getConstantState().equals( fav_btn.getContext().getDrawable(R.drawable.ic_heart_empty).getConstantState()))
{
fav_btn.setImageResource(R.drawable.ic_heart_full);
}else{
fav_btn.setImageResource(R.drawable.ic_heart_empty);
}
});
return view;
}
}

服务：

public class BackgroundSoundService extends Service {
String  song_string;
int x;
private static final String TAG = "BackgroundSoundService";
MediaPlayer player;

public IBinder onBind(Intent arg0) {
Log.i(TAG, "onBind()" );
return null;
}
@Override
public void onCreate() {
super.onCreate();
}
@Override
public void onStart(Intent intent, int startId) {
super.onStart(intent, startId);
}
public int onStartCommand(Intent intent, int flags, int startId) {

song_string= intent.getStringExtra("uri");
if (song_string != null) {
System.out.println("Song string : " + song_string);
player = MediaPlayer.create(this, Uri.parse(song_string));
player.setLooping(false); // Set looping
player.setVolume(0.5f, 0.5f);
if (!(String.valueOf(x) == null || String.valueOf(x).isEmpty())) {
player.seekTo(x);
}
player.start();
}
return Service.START_STICKY;
}
public IBinder onUnBind(Intent arg0) {
Log.i(TAG, "onUnBind()");
return null;
}
public void onStop() {
Log.i(TAG, "onStop()");
}
public void onPause() {
Log.i(TAG, "onPause()");
x=player.getCurrentPosition();
player.pause();
}
@Override
public void onDestroy() {
if(player!=null) {
player.stop();
player.reset();
player.release();
Log.i(TAG, "onCreate() , service stopped...");
}
}
@Override
public void onLowMemory() {
Log.i(TAG, "onLowMemory()");
}

}

事先非常感谢您的帮助。

Answer 1

看看这个项目，它由谷歌维护，它将向您展示创建android音乐播放器应用程序的正确方法。https://github.com/android/uamp