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Push Notification Trigger on Windows Phone 8.1 Silverlight

I'm working on the "feature" the push notification trigger available in Windows phone 8.1. My goal is to make this work with a Windows phone Silverlight 8.1 project. As far as I know, it should work based on my reading.
After 2 days, I'm totally stuck. No matter what i'm trying. When I send a raw notification to my app, my app is canceled and I'm back to the windows menu.
The output :
The program '[1852] BACKGROUNDTASKHOST.EXE' has exited with code 1 (0x1).
The program '[2712] AgHost.exe' has exited with code 1 (0x1).
State :
The app receives the notification. It trigger OnPushNotificationReceived. (After this event, the app is canceled)
The Push Notification task is declared and the entry point is defined to Push.Notification.
I create a Windows Runtime Component for Windows phone 8.1 in order to run the background task.
The background task is well registered.
private async void RegisterBackgroundTask()
{
UnregisterBackgroundTask(taskName);
BackgroundAccessStatus backgroundStatus = await BackgroundExecutionManager.RequestAccessAsync();
if (backgroundStatus != BackgroundAccessStatus.Denied && backgroundStatus != BackgroundAccessStatus.Unspecified)
{
try
{
BackgroundTaskBuilder taskBuilder = new BackgroundTaskBuilder();
taskBuilder.Name = taskName;
PushNotificationTrigger trigger = new PushNotificationTrigger();
taskBuilder.SetTrigger(trigger);
taskBuilder.TaskEntryPoint = "Push.Notification";
BackgroundTaskRegistration task = taskBuilder.Register();
}
catch (Exception ex)
{ }
}
}
The background task :
public sealed class Notification
{
public void Run(IBackgroundTaskInstance taskInstance)
{
Debug.WriteLine("Background starting...");
Debug.WriteLine("Background completed!");
}
}
I have no clue about what I'm doing wrong.
Is there someone who make it works ? (Not in theory)
For information, I have 2 warnings that worrying me :
I have a mismatch in the process architecture in my 2 projects. My windows phone project use "Any CPU" (can"t change that). My windows runetime component project use "ARM". If I use "Any CPU" wor my WinRT, i got an errror :
/platform:anycpu32bitpreferred can only be used with /t:exe, /t:winexe and /t:appcontainerexe
There is a conflict on a dependent assembly of the 2 projects. Seems to be
Found conflicts between different versions of the same dependent assembly. In Visual Studio, double-click this warning (or select it and press Enter) to fix the conflicts; otherwise, add the following binding redirects to the "runtime" node in the application configuration file:
Thanks in advance

I did finally make it works.
There was an error in my initial code I forgot to implement IBackgroundTask :
public sealed class Notification : IBackgroundTask
{
public void Run(IBackgroundTaskInstance taskInstance)
{
Debug.WriteLine("Background starting...");
Debug.WriteLine("Background completed!");
}
}
And I had to make my Task async...
public async void Run(IBackgroundTaskInstance taskInstance)
{
BackgroundTaskDeferral deferral = taskInstance.GetDeferral();
// perform your async task and then call deferral complete
await Test();
deferral.Complete();
}
private static async Task Test()
{
//TODO with an await
}
Hope this'll help someone.

How to Making a Background Task Reschedule Itself

I am trying to make a background task reschedule itself at the end of it's task. but when I go to test it doesn't seem to activate. The task runs initially from the frontend successfully. When I check the lifecycle Events after it finishes I see it's name and two blank ones. When I run the blank ones it runs it, not sure what I am doing that causes them. I am tryin to test with a 16 min time trigger but it doesn't seem to ever run again. This is the code:
var SleepyBand_TaskName = "DataHandlerTask";
foreach (var task in BackgroundTaskRegistration.AllTasks)
{
if (task.Value.Name == SleepyBand_TaskName)
{
task.Value.Unregister(true);
}
}
var builder = new BackgroundTaskBuilder();
var trigger = new TimeTrigger(16, false);
builder.Name = SleepyBand_TaskName;
builder.TaskEntryPoint = "SleepyBand_BackgroundTasks.DataHandlerTask";
builder.SetTrigger(trigger);
builder.Register();

TimeTrigger only work for lock-screen apps.
On Windows, a background task will only run using a TimeTrigger if you have requested that your app be placed on the lock screen with a call to RequestAccessAsync and the user accepts the prompt
You would need to use a MaintenanceTrigger

eI would just use System.Threading.Tasks.Task to start threads. Like this you can reshedule a task:
public void Test() {
Task.Run(() => DoSomething());
}
private void DoSomething() {
//Do Something here....
//Do Something again...
Task.Run(() => DoSomething());
}
If you need delays use something like this: https://actionscheduler.codeplex.com/

Windows RT - Background Task Not Firing

I am implementing a background task for my Windows Store Application (Win 8.1 App). I have written a very simple test class, registered it, prompted for access, but when I choose to debug the task from the debug toolbar, nothing happens. I have also waited 15 minutes multiple times today and it does not output anything. Yet, it shows (from the code perspective) that the Task is registered and I am not getting any exceptions generated.
The Background Task:
public sealed class BGFunMessage : IBackgroundTask
{
public void Run(IBackgroundTaskInstance taskInstance)
{
Debug.WriteLine("Background " + taskInstance.Task.Name + " Starting...");
}
}
The Register Class:
public class RegisterWorkers
{
public static async void Run()
{
var taskRegistered = false;
var taskName = "BGFunMessage";
BackgroundTaskRegistration bTask = null;
foreach (var task in BackgroundTaskRegistration.AllTasks)
{
if (task.Value.Name == taskName)
{
//taskRegistered = true;
bTask = (BackgroundTaskRegistration)(task.Value);
bTask.Unregister(true);
break;
}
}
if (!taskRegistered)
{
string entryPoint = typeof(BGFunMessage).FullName;
bTask = RegisterBackgroundTask(entryPoint, taskName);
}
}
public static BackgroundTaskRegistration RegisterBackgroundTask(string taskEntryPoint, string name)
{
var builder = new BackgroundTaskBuilder();
builder.Name = name;
builder.TaskEntryPoint = taskEntryPoint;
builder.SetTrigger(new TimeTrigger(15, false));
BackgroundTaskRegistration task = null;
try
{
task = builder.Register();
}
catch (Exception ex)
{
LiveLog.WriteException(ex, LogType.WARNING);
}
return task;
}
}
How I call it from a page in my app:
RegisterWorkers.Run();
I have tried following multiple tutorials, that all mostly say the same thing. I am also using the MSDN Samples downloaded from GitHub and I don't see anything on the surface that makes their code any different from mine (apart from that their Register method returns a Task<>). I am able to debug the Sample project background tasks, but not my own. Is there something I am doing incorrectly here? Thanks.

After many hours of troubleshooting, I have found the solution to my problem. I am unsure of why this must be the case, but it works. Originally (unspecified above), I had the Background Task in the same project as my app. The ONLY difference I could find across the board was that everywhere I seen, the background tasks were in a WINDOWS RUNTIME COMPONENT project. I pulled my code out and into its own project, and referenced the .DLL and now it all works fine.
I should note however, if anyone ever needs this fix--that now I no longer have access to any of my data or SyncContext from Azure Mobile Services as it currently stands. I have no idea what I am going to have to re-architect to make it work now, but the issue above is now resolved.
I will assume, that you should always have a Shared Code library project that your main app project should reference, that way my Background Task can also reference the shared project and I can still have access to my models and other data.

BACKGROUNDTASKHOST.EXE' has exited with code 1 (0x1) - Geofence issue

I am writing Windows Phone 8.1 Application using GeoFence API. My problem is that I can't trigger change of location in Background Task, because app exits with code 1.
I have read multiple threads about this error, but no solution solved my problem.
I have checked if my BackgroundTask is a Runtime Component, and it is.
I have checked name of my class and it is correct.
I have checked if I use any await function in my BackgroundTask function and I didn't find any.
I have checked if I registered Background Task in app manifest and yes, I did (with entry point ofc)
In fact error appears even before running Run function from BackgroundTask.
namespace BackgroundTask
{
public sealed class geoFenceBackgroundTask : IBackgroundTask
{
public void Run(IBackgroundTaskInstance taskInstance)
{
ToastTemplateType toastTemplate = ToastTemplateType.ToastText02;
XmlDocument toastXml = ToastNotificationManager.GetTemplateContent(toastTemplate);
XmlNodeList toastTextElements = toastXml.GetElementsByTagName("text");
toastTextElements[0].AppendChild(toastXml.CreateTextNode("MY APP"));
toastTextElements[1].AppendChild(toastXml.CreateTextNode("Test"));
//IXmlNode toastNode = toastXml.SelectSingleNode("/toast");
//XmlElement audio = toastXml.CreateElement("audio");
ToastNotification toast = new ToastNotification(toastXml);
ToastNotificationManager.CreateToastNotifier().Show(toast);
}
}
}
And my register function:
async private void RegisterBackgroundTask()
{
// Get permission for a background task from the user. If the user has already answered once,
// this does nothing and the user must manually update their preference via PC Settings.
BackgroundAccessStatus backgroundAccessStatus = await BackgroundExecutionManager.RequestAccessAsync();
// Regardless of the answer, register the background task. If the user later adds this application
// to the lock screen, the background task will be ready to run.
// Create a new background task builder
BackgroundTaskBuilder geofenceTaskBuilder = new BackgroundTaskBuilder();
geofenceTaskBuilder.Name = "geoFenceBackgroundTask";
geofenceTaskBuilder.TaskEntryPoint = "BackgroundTask.geoFenceBackgroundTask";
// Create a new location trigger
var trigger = new LocationTrigger(LocationTriggerType.Geofence);
// Associate the locationi trigger with the background task builder
geofenceTaskBuilder.SetTrigger(trigger);
// If it is important that there is user presence and/or
// internet connection when OnCompleted is called
// the following could be called before calling Register()
// SystemCondition condition = new SystemCondition(SystemConditionType.UserPresent | SystemConditionType.InternetAvailable);
// geofenceTaskBuilder.AddCondition(condition);
// Register the background task
var geofenceTask = geofenceTaskBuilder.Register();
geofenceTask.Completed += (sender, args) =>
{
// MY CODE HERE
};
geofenceTask = geofenceTaskBuilder.Register();
}
I have no other ideas. Any help?

just stumbled upon a similar issue (Visual Studio stopped Debugging when I started the Background Task over the "Lifecyle-Events-Dropdown", stating "BACKGROUNDTASKHOST.EXE' has exited with code 1 (0x1)" in the Console-Output-Window.
Adding the missing reference to my Tasks-Assembly (winmd) Project in the WP8 Project solved it.

The project BackgroundTask need be (windows runtime component).

Event for connection status changing in Windows 8

Is there an event to handle when connection status change?
For example, my app is like OutLook. I would like to handle an event to know when there is Internet connection and then to send all pending e-mails.
Now I can check periodically if there is Internet connection, but it seems a poor solution to me. I would to solve it using an event.

Your best choice would be implementing a background task. This way you could send the pending e-mails even if your app is not open any more when the internet connection becomes available.
When registering a background task you can set a trigger and a condition to configure when you want your task to run:
var trigger = new SystemTrigger(SystemTriggerType.InternetAvailable, false);
var condition = new SystemCondition(SystemConditionType.InternetAvailable);
var builder = new BackgroundTaskBuilder();
builder.Name = "Send pending e-mails task";
builder.TaskEntryPoint = "Tasks.SendPendingEmailTask";
builder.SetTrigger(trigger);
builder.AddCondition(condition);
var task = builder.Register();
Your background task must implement the IBackgroundTask interface. When the task is triggered, the Run method will be called:
public sealed class SendPendingEmailTask : IBackgroundTask
{
public void Run(IBackgroundTaskInstance taskInstance)
{
var deferral = taskInstance.GetDeferral();
// send your e-mails here
deferral.Complete();
}
}