Xamarin.Forms
Pushnotifikationer

Anmärkningar

Tryck på aviseringar för iOS med Azure

För att starta registreringen för push-aviseringar måste du köra koden nedan.

// registers for push
var settings = UIUserNotificationSettings.GetSettingsForTypes(
    UIUserNotificationType.Alert
    | UIUserNotificationType.Badge
    | UIUserNotificationType.Sound,
    new NSSet());

UIApplication.SharedApplication.RegisterUserNotificationSettings(settings);
UIApplication.SharedApplication.RegisterForRemoteNotifications();

Den här koden kan antingen köras direkt när appen startar i FinishedLaunching i filen AppDelegate.cs . Eller så kan du göra det när en användare beslutar att de vill aktivera push-aviseringar.

Att köra den här koden utlöser en varning för att uppmana användaren om de accepterar att appen kan skicka meddelanden till dem. Så implementera också ett scenario där användaren förnekar det!

Dessa är de händelser som behöver implementeras för att implementera push-aviseringar på iOS. Du kan hitta dem i filen AppDelegate.cs .

// We've successfully registered with the Apple notification service, or in our case Azure
public override void RegisteredForRemoteNotifications(UIApplication application, NSData deviceToken)
{
   // Modify device token for compatibility Azure
    var token = deviceToken.Description;
    token = token.Trim('<', '>').Replace(" ", "");
    
    // You need the Settings plugin for this!
    Settings.DeviceToken = token;
    
    var hub = new SBNotificationHub("Endpoint=sb://xamarinnotifications-ns.servicebus.windows.net/;SharedAccessKeyName=DefaultListenSharedAccessSignature;SharedAccessKey=<your own key>", "xamarinnotifications");
    
    NSSet tags = null; // create tags if you want, not covered for now
    hub.RegisterNativeAsync(deviceToken, tags, (errorCallback) =>
    {
        if (errorCallback != null)
        {
            var alert = new UIAlertView("ERROR!", errorCallback.ToString(), null, "OK", null);
            alert.Show();
        }
    });
}

// We've received a notification, yay!
public override void ReceivedRemoteNotification(UIApplication application, NSDictionary userInfo)
{
    NSObject inAppMessage;

    var success = userInfo.TryGetValue(new NSString("inAppMessage"), out inAppMessage);

    if (success)
    {
        var alert = new UIAlertView("Notification!", inAppMessage.ToString(), null, "OK", null);
        alert.Show();
    }
}

// Something went wrong while registering!
public override void FailedToRegisterForRemoteNotifications(UIApplication application, NSError error)
{
   var alert = new UIAlertView("Computer says no", "Notification registration failed! Try again!", null, "OK", null);
                    
   alert.Show();
}

När ett meddelande mottas är det så det ser ut.

Tryck på aviseringar för Android med Azure

Implementering på Android är lite mer arbete och kräver att en specifik Service ska implementeras.

Låt oss först kontrollera om vår enhet kan ta emot push-aviseringar, och i så fall registrera den hos Google. Detta kan göras med den här koden i filen MainActivity.cs .

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

    global::Xamarin.Forms.Forms.Init(this, bundle);

    // Check to ensure everything's setup right for push
    GcmClient.CheckDevice(this);
    GcmClient.CheckManifest(this);
    GcmClient.Register(this, NotificationsBroadcastReceiver.SenderIDs);

    LoadApplication(new App());
}

Avsändar-ID: erna kan hittas i koden under och är projektnumret som du får från Google-utvecklarens instrumentbräda för att kunna skicka pushmeddelanden.

using Android.App;
using Android.Content;
using Gcm.Client;
using Java.Lang;
using System;
using WindowsAzure.Messaging;
using XamarinNotifications.Helpers;

// These attributes are to register the right permissions for our app concerning push messages
[assembly: Permission(Name = "com.versluisit.xamarinnotifications.permission.C2D_MESSAGE")]
[assembly: UsesPermission(Name = "com.versluisit.xamarinnotifications.permission.C2D_MESSAGE")]
[assembly: UsesPermission(Name = "com.google.android.c2dm.permission.RECEIVE")]

//GET_ACCOUNTS is only needed for android versions 4.0.3 and below
[assembly: UsesPermission(Name = "android.permission.GET_ACCOUNTS")]
[assembly: UsesPermission(Name = "android.permission.INTERNET")]
[assembly: UsesPermission(Name = "android.permission.WAKE_LOCK")]

namespace XamarinNotifications.Droid.PlatformSpecifics
{
    // These attributes belong to the BroadcastReceiver, they register for the right intents
    [BroadcastReceiver(Permission = Constants.PERMISSION_GCM_INTENTS)]
    [IntentFilter(new[] { Constants.INTENT_FROM_GCM_MESSAGE },
    Categories = new[] { "com.versluisit.xamarinnotifications" })]
    [IntentFilter(new[] { Constants.INTENT_FROM_GCM_REGISTRATION_CALLBACK },
    Categories = new[] { "com.versluisit.xamarinnotifications" })]
    [IntentFilter(new[] { Constants.INTENT_FROM_GCM_LIBRARY_RETRY },
    Categories = new[] { "com.versluisit.xamarinnotifications" })]

    // This is the bradcast reciever
    public class NotificationsBroadcastReceiver : GcmBroadcastReceiverBase<PushHandlerService>
    {
        // TODO add your project number here
        public static string[] SenderIDs = { "96688------" };
    }

    [Service] // Don't forget this one! This tells Xamarin that this class is a Android Service
    public class PushHandlerService : GcmServiceBase
    {
        // TODO add your own access key
        private string _connectionString = ConnectionString.CreateUsingSharedAccessKeyWithListenAccess(
            new Java.Net.URI("sb://xamarinnotifications-ns.servicebus.windows.net/"), "<your key here>");

        // TODO add your own hub name
        private string _hubName = "xamarinnotifications";

        public static string RegistrationID { get; private set; }

        public PushHandlerService() : base(NotificationsBroadcastReceiver.SenderIDs)
        {
        }

        // This is the entry point for when a notification is received
        protected override void OnMessage(Context context, Intent intent)
        {
            var title = "XamarinNotifications";

            if (intent.Extras.ContainsKey("title"))
                title = intent.Extras.GetString("title");

            var messageText = intent.Extras.GetString("message");

            if (!string.IsNullOrEmpty(messageText))
                CreateNotification(title, messageText);
        }

        // The method we use to compose our notification
        private void CreateNotification(string title, string desc)
        {
            // First we make sure our app will start when the notification is pressed
            const int pendingIntentId = 0;
            const int notificationId = 0;

            var startupIntent = new Intent(this, typeof(MainActivity));
            var stackBuilder = TaskStackBuilder.Create(this);

            stackBuilder.AddParentStack(Class.FromType(typeof(MainActivity)));
            stackBuilder.AddNextIntent(startupIntent);

            var pendingIntent =
                stackBuilder.GetPendingIntent(pendingIntentId, PendingIntentFlags.OneShot);

            // Here we start building our actual notification, this has some more
            // interesting customization options!
            var builder = new Notification.Builder(this)
                .SetContentIntent(pendingIntent)
                .SetContentTitle(title)
                .SetContentText(desc)
                .SetSmallIcon(Resource.Drawable.icon);

            // Build the notification
            var notification = builder.Build();
            notification.Flags = NotificationFlags.AutoCancel;

            // Get the notification manager
            var notificationManager =
                GetSystemService(NotificationService) as NotificationManager;

            // Publish the notification to the notification manager
            notificationManager.Notify(notificationId, notification);
        }

        // Whenever an error occurs in regard to push registering, this fires
        protected override void OnError(Context context, string errorId)
        {
            Console.Out.WriteLine(errorId);
        }

        // This handles the successful registration of our device to Google
        // We need to register with Azure here ourselves
        protected override void OnRegistered(Context context, string registrationId)
        {
            var hub = new NotificationHub(_hubName, _connectionString, context);

            Settings.DeviceToken = registrationId;

            // TODO set some tags here if you want and supply them to the Register method
            var tags = new string[] { };

            hub.Register(registrationId, tags);
        }

        // This handles when our device unregisters at Google
        // We need to unregister with Azure
        protected override void OnUnRegistered(Context context, string registrationId)
        {
            var hub = new NotificationHub(_hubName, _connectionString, context);

            hub.UnregisterAll(registrationId);
        }
    }
}

Ett exempel på en anmälan på Android ser ut så här.

Tryck på aviseringar för Windows Phone med Azure

På Windows Phone måste något som koden under implementeras för att börja arbeta med push-aviseringar. Detta kan hittas i filen App.xaml.cs

protected async override void OnLaunched(LaunchActivatedEventArgs e)
{
    var channel = await PushNotificationChannelManager.CreatePushNotificationChannelForApplicationAsync();
 
    // TODO add connection string here
    var hub = new NotificationHub("XamarinNotifications", "<connection string with listen access>");
    var result = await hub.RegisterNativeAsync(channel.Uri);
 
    // Displays the registration ID so you know it was successful
    if (result.RegistrationId != null)
    {
        Settings.DeviceToken = result.RegistrationId;
    }
 
    // The rest of the default code is here
}

Glöm inte att aktivera funktionerna i filen Package.appxmanifest .

Ett exempel på en push-anmälan kan se ut så här: