Push Notifications: notification text vs other data - xamarin.forms

Question

I have a Xamarin.Forms app that receives push notifications. Upon receiving the notification, the user clicks on it, and the app processes data that comes with the notification, and acts accordingly. But I have an issue with iOS part of the app. Instead of user friendly notification text, it displays the data in json format, which is not intended for this purpose.
Here is how the notification is sent:
private static async Task SendTemplateNotificationsAsync(string json, ILogger log)
{
NotificationHubClient hub = NotificationHubClient.CreateClientFromConnectionString(NotificationDispatcherConstants.FullAccessConnectionString, NotificationDispatcherConstants.NotificationHubName);
Dictionary<string, string> templateParameters = new Dictionary<string, string>();
foreach (var tag in NotificationDispatcherConstants.SubscriptionTags)
{
templateParameters["messageParam"] = json;
try
{
await hub.SendTemplateNotificationAsync(templateParameters, tag);
...
}
catch (Exception ex)
{
log.LogInformation($"Failed to send template notification: {ex.Message}");
}
}
}
Here are the constants:
public static string APNTemplateBody { get; set; } = "{\"aps\":{\"alert\":\"$(messageParam)\"}}";
public const string NotificationTokenKey = "NotificationTokenKey";
Here is how the notifications are processed in AppDelegate.cs:
[Export("userNotificationCenter:didReceiveNotificationResponse:withCompletionHandler:")]
public void DidReceiveNotificationResponse(UNUserNotificationCenter center, UNNotificationResponse response, Action completionHandler)
{
completionHandler();
NSDictionary userInfo = response.Notification.Request.Content.UserInfo;
ProcessNotification(userInfo);
}
[Export("userNotificationCenter:willPresentNotification:withCompletionHandler:")]
public void WillPresentNotification(UNUserNotificationCenter center, UNNotification notification, Action<UNNotificationPresentationOptions> completionHandler)
{
completionHandler(UNNotificationPresentationOptions.Sound | UNNotificationPresentationOptions.Alert);
NSDictionary userInfo = notification.Request.Content.UserInfo;
ProcessNotification(userInfo);
}
void ProcessNotification(NSDictionary options)
{
Task.Run(() =>
{
// make sure we have a payload
if (options != null && options.ContainsKey(new NSString("aps")))
{
// get the APS dictionary and extract message payload. Message JSON will be converted
// into a NSDictionary so more complex payloads may require more processing
NSDictionary aps = options.ObjectForKey(new NSString("aps")) as NSDictionary;
string payload = string.Empty;
NSString payloadKey = new NSString("alert");
if (aps.ContainsKey(payloadKey))
{
payload = aps[payloadKey].ToString();
}
if (!string.IsNullOrWhiteSpace(payload))
{
if (App.UserContext.IsEmployee)
{
App.NewCall(payload);
}
}
}
else
{
Debug.WriteLine($"Received request to process notification but there was no payload.");
}
});
}
App.NewCall(payload); is the code that makes the payload to be handled by the app, which is correct. But I don't want this payload to be displayed as the notification text. How can I set the text to something different and user-friendly?

Answer 1

You don't need to handle the message if you just want to show a default UI:
see step 12 in this doc, make sure your payload is in a right format:
void ProcessNotification(NSDictionary options, bool fromFinishedLaunching)
{
// Check to see if the dictionary has the aps key. This is the notification payload you would have sent
if (null != options && options.ContainsKey(new NSString("aps")))
{
//Get the aps dictionary
NSDictionary aps = options.ObjectForKey(new NSString("aps")) as NSDictionary;
string alert = string.Empty;
//Extract the alert text
// NOTE: If you're using the simple alert by just specifying
// " aps:{alert:"alert msg here"} ", this will work fine.
// But if you're using a complex alert with Localization keys, etc.,
// your "alert" object from the aps dictionary will be another NSDictionary.
// Basically the JSON gets dumped right into a NSDictionary,
// so keep that in mind.
if (aps.ContainsKey(new NSString("alert")))
alert = (aps [new NSString("alert")] as NSString).ToString();
//If this came from the ReceivedRemoteNotification while the app was running,
// we of course need to manually process things like the sound, badge, and alert.
if (!fromFinishedLaunching)
{
//Manually show an alert
if (!string.IsNullOrEmpty(alert))
{
var myAlert = UIAlertController.Create("Notification", alert, UIAlertControllerStyle.Alert);
myAlert.AddAction(UIAlertAction.Create("OK", UIAlertActionStyle.Default, null));
UIApplication.SharedApplication.KeyWindow.RootViewController.PresentViewController(myAlert, true, null);
}
}
}
}
If you want to use custom user interfaces, you can create a notification content extension and create your UI there.