Xamarin的Android通知崩潰

Question

我得到以下異常：

Java.Lang.IllegalStateException：指定的孩子已經有一個父。您必須在孩子的父母的拳頭上調用removeVeiw（）。

運行以下代碼塊時。這一切都始於我的「表單」頁面，並使用按鈕按鈕使用警報管理器生成預定通知。問題是，如果點擊通知，如果應用程序仍處於活動狀態，則會引發上述異常。

如果我在手機上切換應用程序，然後單擊通知，它會使應用程序按預期恢復，而不會發生崩潰。

下面是有問題的代碼段用於此工作流程：

從xamarin頁：

private void BtnStartJob_Clicked(object sender, EventArgs e) 
    { 
     lblStatus.Text = ""; 
     if (btnStartJob.Text == "Start Job") 
     { 
      tmrToggle.StartCommand.Execute(null); 
      App.Manager.StartJob(App.Manager.currentTimesheet.ProjectID); 
      btnStartJob.Text = "Start Break"; 
     } 
     else if (btnStartJob.Text == "End Break") 
     { 
      tmrAlert.PauseCommand.Execute(null); 
      tmrToggle.StartCommand.Execute(null); 
      App.Manager.EndBreak(App.Manager.currentTimesheet.TimesheetID); 
      btnStartJob.Text = "Start Break"; 
      var notificationService = DependencyService.Get<INotificationService>(); 
      notificationService.CancelNotification(); 
     } 
     else if (btnStartJob.Text == "Start Break") 
     { 
      tmrAlert.StartCommand.Execute(null); 
      tmrToggle.PauseCommand.Execute(null); 
      App.Manager.StartBreak(App.Manager.currentTimesheet.TimesheetID); 
      btnStartJob.Text = "End Break"; 

      // schedule the notification here. 
      var notificationService = DependencyService.Get<INotificationService>(); 
      notificationService.CreateNotification("Take Action", "Your break started 1 second ago, please take action.", TimeSpan.FromSeconds(15).Ticks); 
     } 
    } 

NotificationService

public class NotificationService : INotificationService 
{ 

    public void CancelNotification() 
    { 
     var alarmIntent = new Intent(Android.App.Application.Context, typeof(AlarmReceiver));    
     var pending = PendingIntent.GetBroadcast(Android.App.Application.Context, 0, alarmIntent, PendingIntentFlags.UpdateCurrent); 

     var alarmManager = Android.App.Application.Context.GetSystemService("alarm").JavaCast<AlarmManager>(); 
     alarmManager.Cancel(pending);    
    } 

    public void CreateNotification(string title, string message, long durationInTicks) 
    { 
     var duration = TimeSpan.FromTicks(durationInTicks); 

     var alarmIntent = new Intent(Forms.Context, typeof(AlarmReceiver)); 
     alarmIntent.PutExtra("title", title); 
     alarmIntent.PutExtra("message", message); 

     var pending = PendingIntent.GetBroadcast(Android.App.Application.Context, 0, alarmIntent, PendingIntentFlags.UpdateCurrent); 

     var alarmManager = Android.App.Application.Context.GetSystemService("alarm").JavaCast<AlarmManager>(); 
     alarmManager.Set(AlarmType.ElapsedRealtime, duration.Milliseconds, pending); 
    } 
}  

報警接收機：

[BroadcastReceiver] 
class AlarmReceiver : BroadcastReceiver 
{ 
    public override void OnReceive(Context context, Intent intent) 
    { 
     var message = intent.GetStringExtra("message"); 
     var title = intent.GetStringExtra("title"); 

     var resultIntent = new Intent(context, typeof(MainActivity)); 
     resultIntent.SetFlags(ActivityFlags.NewTask | ActivityFlags.ClearTask); 

     var pending = PendingIntent.GetActivity(context, 0, 
      resultIntent, 
      PendingIntentFlags.CancelCurrent); 

     var builder = 
      new Notification.Builder(context) 
       .SetContentTitle(title) 
       .SetContentText(message)      
       .SetSmallIcon(Resource.Drawable.WESSUClogo) 
       .SetDefaults(NotificationDefaults.All); 

     builder.SetContentIntent(pending); 

     var notification = builder.Build(); 

     var manager = NotificationManager.FromContext(context); 
     manager.Notify(1337, notification); 
    } 
} 

MainActivity： 全球:: Xamarin.Forms.Platform.Android.FormsApplicationActivity {

protected override void OnCreate(Bundle bundle) 
    { 
     base.OnCreate(bundle); 

     global::Xamarin.Forms.Forms.Init(this, bundle); 
     LoadApplication(new App());       
    } 
} 

如何解決有什麼建議？對我來說，最大的問題是我需要調用removeView（）的對象是什麼？這個異常在LoadApplication（newApp（））上拋出;在我的MainActivity線。

由於完整的堆棧跟蹤非常長，請點擊here獲取pastebin。

Answer 1

我自己發現了答案。

的AlarmReceiver內的所有我需要做的是這樣的：

resultIntent.SetFlags（ActivityFlags.Singletop）;