java - 如果我使用Android服务，为什么我的应用程序会关闭？

我正在尝试制作一个简单的音频播放器。当我在没有服务的主活动中创建它时，它可以正常工作，正在播放音乐（如果按电源按钮以关闭屏幕，则它可以工作），并且在打开屏幕后仍然可以正常工作。但是，如果我使用服务在后台播放音乐，则当我按下电源按钮打开屏幕时，我的应用程序会关闭。

public class MainActivity extends AppCompatActivity {

    static ArrayList<HashMap<String, Object>> listSongs = new ArrayList<>();
    Intent intent;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        listSongs = getAllMusicInfo();
        intent = new Intent(this, BackgroundPlayer.class);

        Button buttonStart = (Button) findViewById(R.id.startService);
        buttonStart.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startService(intent);
                Toast.makeText(MainActivity.this, "It's started", Toast.LENGTH_SHORT).show();
            }
        });

        Button buttonStop = (Button) findViewById(R.id.StopService);
        buttonStop.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                stopService(intent);
                Toast.makeText(MainActivity.this, "It's stopped", Toast.LENGTH_SHORT).show();
            }
        });
    }

    public class BackgroundPlayer extends Service implements MediaPlayer.OnCompletionListener {
    MediaPlayer player;

    @Override
    public void onCreate() {
        super.onCreate();

        player = new MediaPlayer();

        try {
            player.setDataSource((String) MainActivity.listSongs.get(0).get("path"));
            player.prepare();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        player.start();
        return START_STICKY;
    }

    @Override
    public void onCompletion(MediaPlayer mp) {}
}

06-05 09:58:54.206 31873-31873/com.vitaliylevashov.serviceplayer V/MediaPlayer: start

06-05 09：58：54.206 31873-31885 / com.vitaliylevashov.serviceplayer V / MediaPlayer：收到消息msg = 6，ext1 = 0，ext2 = 0
06-05 09：58：54.206 31873-31885 / com.vitaliylevashov.serviceplayer V / MediaPlayer：已收到MEDIA_STARTED
06-05 09：58：54.206 31873-31885 / com.vitaliylevashov.serviceplayer V / MediaPlayer：回调应用程序
06-05 09：58：54.206 31873-31885 / com.vitaliylevashov.serviceplayer V / MediaPlayer：从回调返回
06-05 09：58：54.236 31873-31873 / com.vitaliylevashov.serviceplayer I / MediaPlayer：不要发送意图。 msg.arg1 = 0，msg.arg2 = 0
06-05 09：58：54.236 31873-31873 / com.vitaliylevashov.serviceplayer E / MediaPlayer：应该已经设置了字幕控制器
06-05 09：58：54.256 31873-31873 / com.vitaliylevashov.serviceplayer V / MediaPlayer-JNI：getCurrentPosition：192（msec）
06-05 09：58：54.256 31873-31873 / com.vitaliylevashov.serviceplayer V / MediaPlayer-JNI：isPlaying：1
                                                                                    <<
06-05 09：59：25.526 31873-31873 / com.vitaliylevashov.serviceplayer D / Android运行时：关闭VM
06-05 09：59：25.526 31873-31873 / com.vitaliylevashov.serviceplayer W / dalvikvm：threadid = 1：线程以未捕获的异常退出（group = 0x41660bc0）
06-05 09：59：25.526 31873-31873 / com.vitaliylevashov.serviceplayer E / Android运行时：致命异常：主要
                                                                                   进程：com.vitaliylevashov.serviceplayer，PID：31873
                                                                                   android.database.StaleDataException：尝试在关闭游标后访问游标。
                                                                                       在android.database.BulkCursorToCursorAdaptor.throwIfCursorIsClosed（BulkCursorToCursorAdaptor.java:64）
                                                                                       在android.database.BulkCursorToCursorAdaptor.requery（BulkCursorToCursorAdaptor.java:133）
                                                                                       在android.database.CursorWrapper.requery（CursorWrapper.java:186）
                                                                                       在android.app.Activity.performRestart（Activity.java:5346）
                                                                                       在android.app.ActivityThread.handleSleeping（ActivityThread.java:3487）
                                                                                       在android.app.ActivityThread.access $ 3000（ActivityThread.java:155）
                                                                                       在android.app.ActivityThread $ H.handleMessage（ActivityThread.java:1428）
                                                                                       在android.os.Handler.dispatchMessage（Handler.java:102）
                                                                                       在android.os.Looper.loop（Looper.java:136）
                                                                                       在android.app.ActivityThread.main（ActivityThread.java:5433）
                                                                                       在java.lang.reflect.Method.invokeNative（本机方法）
                                                                                       在java.lang.reflect.Method.invoke（Method.java:515）
                                                                                       在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:1268）
                                                                                       在com.android.internal.os.ZygoteInit.main（ZygoteInit.java:1084）
                                                                                       在dalvik.system.NativeStart.main（本机方法）

最佳答案

在清单中添加服务标签，也许您还没有在清单中添加服务标签

<service android:name=".MyService" />

请求发布错误日志/ logcat