IllegalStateException：在尝试运行RingtoneService时不允许启动服务意图

Question

public class AlarmReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(final Context context, Intent intent) {

        Intent serviceIntent = new Intent(context, RingtonePlayingService.class);
        context.startService(serviceIntent);
    }
}

Intent intent = new Intent(AddAlarm.this, AlarmReceiver.class)
                .putExtra("ALARM_ON", true);
        PendingIntent pendingIntent = PendingIntent.getBroadcast(this.getApplicationContext(), 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);

        alarmManager.set(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pendingIntent);

服务类别如下：

public class RingtonePlayingService extends Service {

    // Player
    MediaPlayer player;
    boolean isRunning;

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

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {

        if (!isRunning) {

            player = MediaPlayer.create(this, R.raw.ringtone);
            player.start();

            this.isRunning = true;

            showNotification();

        }
        else if (isRunning) {

            player.stop();

            this.isRunning = false;

        }

        return START_STICKY;
    }
}

Answer 1

如果您在Android8.0上运行代码，那么这种行为是意料之中的。根据文档，从Android8.0开始，如果应用程序不在前台，就不能在后台启动服务。您需要替换以下内容：

Intent serviceIntent = new Intent(context, RingtonePlayingService.class);
context.startService(serviceIntent);

做

Intent serviceIntent = new Intent(context, RingtonePlayingService.class);
ContextCompat.startForegroundService(context, serviceIntent );

确保在onHandleIntent with通知中调用StartForeground()。您可以参考这一点以获得实现它的详细信息。