启动和停止来自广播接收器的通知

Question

我正在尝试从广播接收器启动状态栏通知，然后从另一个广播接收器停止它，但是出现问题。当USB连接时，我想在状态栏中启动通知，然后当USB断开连接时，我想停止它。我已经设置了两个接收器，并且正在努力从接收器中启动和停止一个接收器，这是代码我目前有

我的代码唯一的错误是该myNotificationManager = (NotificationManager) getSystemService(context.NOTIFICATION_SERVICE);行，该错误仅表明getSystemService未定义，并且它想使该方法（我认为这意味着接收者不像活动那样支持该方法），所以我应该怎么做才能创建和停止接收者的通知，谢谢您的帮助

public class USBConnect extends BroadcastReceiver {

public NotificationManager myNotificationManager;
public static final int NOTIFICATION_ID = 1;

@Override
public void onReceive(Context context, Intent intent) {

    myNotificationManager = (NotificationManager) getSystemService(context.NOTIFICATION_SERVICE);

      CharSequence NotificationTicket = "USB Connected!";
      CharSequence NotificationTitle = "USB Connected!";
      CharSequence NotificationContent = "USB is Connected!";

      Notification notification = new Notification(R.drawable.usbicon, NotificationTicket, 0);
      Intent notificationIntent = new Intent(context, MyClass.class);
      PendingIntent contentIntent = PendingIntent.getActivity(context, 0, notificationIntent, 0);
      notification.setLatestEventInfo(context, NotificationTitle, NotificationContent, contentIntent);
      notification.flags |= Notification.FLAG_ONGOING_EVENT;
      myNotificationManager.notify(NOTIFICATION_ID, notification);
      }
}

然后接收器断开连接，我认为这很好，应该可以工作，我认为我的问题仅在USBConnect类中

public class USBDisCon extends BroadcastReceiver {

@Override
public void onReceive(Context context, Intent intent) {
    NotificationManager notificationManager = (NotificationManager)context.getSystemService(Context.NOTIFICATION_SERVICE); 
    notificationManager.cancel(USBConnect.NOTIFICATION_ID);
    }
}

Answer 1

好吧，我最终自己弄清楚了，以供将来遇到同样问题的人参考，我所要做的就是在getSystemService前面添加上下文，这是我的代码有效

public class USBConnect extends BroadcastReceiver {

public NotificationManager myNotificationManager;
public static final int NOTIFICATION_ID = 1;

@Override
public void onReceive(Context context, Intent intent) {

    myNotificationManager = (NotificationManager) getSystemService(context.NOTIFICATION_SERVICE);

      CharSequence NotificationTicket = "USB Connected!";
      CharSequence NotificationTitle = "USB Connected!";
      CharSequence NotificationContent = "USB is Connected!";

      Notification notification = new Notification(R.drawable.usbicon, NotificationTicket, 0);
      Intent notificationIntent = new Intent(context, MyClass.class);
      PendingIntent contentIntent = PendingIntent.getActivity(context, 0, notificationIntent, 0);
      notification.setLatestEventInfo(context, NotificationTitle, NotificationContent, contentIntent);
      notification.flags |= Notification.FLAG_ONGOING_EVENT;
      myNotificationManager.notify(NOTIFICATION_ID, notification);
      }
}

然后接收器断开连接时，我认为这很好，应该可以工作，我认为我的问题仅在USBConnect类中

public class USBDisCon extends BroadcastReceiver {

@Override
public void onReceive(Context context, Intent intent) {
    NotificationManager notificationManager = (NotificationManager)context.getSystemService(Context.NOTIFICATION_SERVICE); 
    notificationManager.cancel(USBConnect.NOTIFICATION_ID);
    }
}