Windows Phone 8.1 SL推送通知后台任务运行方法过早退出.但它在一个示例演示项目中运行良好

为了在后台保存RAW notification有效负载，我添加了一个Windows Runtime Component项目来实现后台任务执行。我设置了一个名为"BgTask"的类，实现了IBackgroundTask和Run方法。

namespace MyBgTask
{
    public sealed class BgTask : IBackgroundTask
    {
        public void Run(IBackgroundTaskInstance taskInstance)
        {
           var a = taskInstance.GetDeferral();
        string taskName = taskInstance.Task.Name;
        Debug.WriteLine("Background " + taskName + " starting...");
        // Store the content received from the notification so it can be retrieved from the UI.
        //RawNotification notification = (RawNotification)taskInstance.TriggerDetails;
        ApplicationDataContainer settings = ApplicationData.Current.LocalSettings;
        //var pushdata = JsonConvert.DeserializeObject<PushModelData>(notification.Content);
        //var pushdata = notification.Content;
        var pushdata = "anoop";
        if (settings.Values.ContainsKey(taskName))
        {
            var dataaa = settings.Values[taskName].ToString();
            Debug.WriteLine(dataaa);
            var lst = JsonConvert.DeserializeObject<List<string>>(dataaa);
            lst.Add(pushdata);
            var seri = JsonConvert.SerializeObject(lst);
            Debug.WriteLine("saving >>>   " + seri);
            settings.Values[taskName] = seri;
        }
        else
        {
            var lst = new List<string>();
            lst.Add(pushdata);
            var seri = JsonConvert.SerializeObject(lst);
            Debug.WriteLine("saving >>>   " + pushdata);
            settings.Values[taskName] = seri;
        }
        Debug.WriteLine("Background " + taskName + " completed!");
        a.Complete();
        }
     }
}

在Packagemanifest中，我将Pushnotification EntryPoint注册为

MyBgTask.BgTask 

在Main页面中，我注册了任务

    private async void Button_Click(object sender, RoutedEventArgs e)
    {
        BackgroundAccessStatus backgroundStatus = await BackgroundExecutionManager.RequestAccessAsync();
        if (backgroundStatus != BackgroundAccessStatus.Denied && backgroundStatus != BackgroundAccessStatus.Unspecified)
        {
            try
            {
                PushNotificationChannel channel = await PushNotificationChannelManager.CreatePushNotificationChannelForApplicationAsync();
                channel.PushNotificationReceived += OnPushNotification;
                UnregisterBackgroundTask();
                RegisterBackgroundTask();
            }
            catch (Exception ex)
            {
                // ... TODO
            }
        }
    }
    private void OnPushNotification(PushNotificationChannel sender,              PushNotificationReceivedEventArgs args)
    {
    }
    private void RegisterBackgroundTask()
    {
        BackgroundTaskBuilder taskBuilder = new BackgroundTaskBuilder();
        taskBuilder.TaskEntryPoint = "MyBgTask.BgTask";
        taskBuilder.Name = "BgTask";
        PushNotificationTrigger trigger = new PushNotificationTrigger();
        taskBuilder.SetTrigger(trigger);
        try
        {
            BackgroundTaskRegistration task = taskBuilder.Register();
            task.Progress += task_Progress;
            task.Completed += BackgroundTaskCompleted;
            Debug.WriteLine("Registration success: ");
        }
        catch (Exception ex)
        {
            Debug.WriteLine("Registration error: " + ex.Message);
            UnregisterBackgroundTask();
        }
    }
    void task_Progress(BackgroundTaskRegistration sender, BackgroundTaskProgressEventArgs args)
    {
        Deployment.Current.Dispatcher.BeginInvoke(() =>
     {
         Debug.WriteLine("progress");
     });
    }
    private void BackgroundTaskCompleted(BackgroundTaskRegistration sender, BackgroundTaskCompletedEventArgs args)
    {
        Deployment.Current.Dispatcher.BeginInvoke(() =>
          {
              MessageBox.Show("Background work item triggered by raw notification with payload = " + " has completed!");
          });
    }
    private bool UnregisterBackgroundTask()
    {
        foreach (var iter in BackgroundTaskRegistration.AllTasks)
        {
            IBackgroundTaskRegistration task = iter.Value;
            if (task.Name == "BgTask")
            {
                task.Unregister(true);
                return true;
            }
        }
        return false;
    }

设置Packagemanifest中的入口点。当我用大量代码向我的主要项目发送原始通知时，pushnotification event会触发。但问题是，当事件触发时，Run方法中的代码块没有触发。它会自动退出，并显示消息

程序'[4484]BACKGROUNDTASKHOST.EXE'有代码1 (0x1)退出

并且每次都发生。我创建了另一个空白的示例windows phone silverlight项目，并实现了后台任务。我测试了发送RAW通知，现在它工作得很好，Run方法中的代码块做得很好。注意，两个项目都在同一个解决方案中。

我需要澄清以下几点1. 为什么后台任务在进入Run方法时自动退出?2. 这是因为我的项目较大或占用较高的应用程序内存吗?3.我怎样才能确定确切的原因呢?

请帮我想出一个解决方案，以工作的预期!

多谢