1.
®
IBM Software Group
© 2014 IBM Corporation
Using the IBM MobileFirst Platform Foundation (MFP) Xamarin SDK Push
Notifications
for Android
@ajaychebbi
IBM MobileFirst Platform Foundation

2.
IBM Software Group | Cloud - MobileFirst
Innovation for a smarter planet 2
Push Notifications - the basics
Notifications come to your device via the Cloud
services hosted by the OS vendor

Google Cloud Messaging service (GCM)

Apple Push Notification service (APNS)

Windows Notification Service (WNS)

3.
IBM Software Group | Cloud - MobileFirst
Innovation for a smarter planet 3
Push Notifications - the basics

You have to do a bunch of handshakes and registrations e.g. above is for
GCM

Eventually the notification message goes from “your Server”

There is also the maintenance of devices and users and un-installs etc.

Excellent info on how it works at Xamarin.com

4.
IBM Software Group | Cloud - MobileFirst
Innovation for a smarter planet 4
Push Notifications – pre reqs

This is going to be a long process to understand – so hang in there

More info here http://developer.xamarin.com/guides/cross-
platform/application_fundamentals/notifications/android/remote_notificati
ons_in_android/

Setup the Google API project and get the senderID and key
– If you dont have it, get it at https://code.google.com/apis/console

Also make sure you have the “Google APIs” emulator image (a real
device works much faster)

5.
IBM Software Group | Cloud - MobileFirst
Innovation for a smarter planet 5
Push Notifications – MFP setup

Copy
WorklightSampleworklightWorklightSampleappsandroidWorklightSamplepush.
png to Resourcesdrawable

A sample adapter is shipped with the component that will be used to manage the
server side message sending etc
– Copy the componentworklightAssetsPushAdapter sample to
WorklightSampleworklightWorklightSampleadapters
–Create a security test “MySecurityTest” in
XtestworklightXtestserverconfauthenticationConfig.xml under <securityTests>
<securityTests>
<mobileSecurityTest name="MySecurityTest">
<testUser realm="SampleAppRealm"/>
<testDeviceId provisioningType="none"/>
</mobileSecurityTest>
.
.
</securityTests>

6.
IBM Software Group | Cloud - MobileFirst
Innovation for a smarter planet 6
Push Notifications – Worklight setup

Add the Google API Key and sender ID in
WorklightSampleworklightWorklightSampleappsandroidWorklightSam
pleapplication-descriptor.xml

Also add the securityTest as “MySecurityTest”
<nativeAndroidApp id="androidXtest" platformVersion="6.2.0.00.20140825-1637"
version="1.0" xmlns="http://www.worklight.com/native-android-descriptor"
securityTest="MySecurityTest">
<displayName>androidXtest</displayName>
<description>androidXtest</description>
<pushSender key="YOUR_GCM_KEY" senderId="YOUR_GCM_ID"/>
<publicSigningKey></publicSigningKey>
<packageName></packageName>
</nativeAndroidApp>

Add the GCMSenderID to assetswlclient.properties
#For Push Notifications,uncomment below line and assign value to it
GcmSenderId = YOUR_GCM_ID

7.
IBM Software Group | Cloud - MobileFirst
Innovation for a smarter planet 7
Push Notifications – App
Android application requires the following three things:
•
Permissions - An Android application must be granted permission to use the internet
and to receive messages from Google Cloud Messaging.
•
BroadcastReceiver - A BroadcastReceiver must be configured to listen for the
Intents that the Google Services Framework will publish when a message is received
from Google Cloud Messaging.
•
IntentService - The BroadcastReceiver will not handle the Intents itself, instead it will
invoke an IntentService that will process the messages.

8.
IBM Software Group | Cloud - MobileFirst
Innovation for a smarter planet 8
Push Notifications – App Configuration
Define Permissions in PropertiesAssemblyInfo.cs
// This will prevent other apps on the device from receiving GCM messages for this app
// It is crucial that the package name does not start with an uppercase letter - this is forbidden by Android.
[assembly: Permission(Name = "@PACKAGE_NAME@.permission.C2D_MESSAGE")]
[assembly: UsesPermission(Name = "@PACKAGE_NAME@.permission.C2D_MESSAGE")]
// Gives the app permission to register and receive messages.
[assembly: UsesPermission(Name = "com.google.android.c2dm.permission.RECEIVE")]
// This permission is necessary only for Android 4.0.3 and below.
[assembly: UsesPermission(Name = "android.permission.GET_ACCOUNTS")]
// Need to access the internet for GCM
[assembly: UsesPermission(Name = "android.permission.INTERNET")]
// Needed to keep the processor from sleeping when a message arrives
[assembly: UsesPermission(Name = "android.permission.WAKE_LOCK")]

9.
IBM Software Group | Cloud - MobileFirst
Innovation for a smarter planet 9
Push Notifications – App Configuration
BroadcastReceiver and Intent
Define BroadcastReceiver and Intent Service in propertiesAndroidManifest.xml
Worklight provides a inbuilt broadcast receiver and Intent service – so just add them to the
manifest
<service android:name="com.worklight.wlclient.push.GCMIntentService" />
<receiver android:name="com.worklight.wlclient.push.WLBroadcastReceiver"
android:permission="com.google.android.c2dm.permission.SEND">
<intent-filter>
<action android:name="com.google.android.c2dm.intent.RECEIVE" />
<category android:name="worklightsample.android" />
</intent-filter>
<intent-filter>
<action android:name="com.google.android.c2dm.intent.REGISTRATION" />
<category android:name="worklightsample.android" />
</intent-filter>
</receiver>

10.
IBM Software Group | Cloud - MobileFirst
Innovation for a smarter planet 10
Push Notifications – App Configuration
Define a IntentFilter for a activity in the app
•
Make sure app_name in Strings.xml is WorklightSample.Android
•
Edit MainActivity.cs and add the following IntentFilter
[IntentFilter (new[]{" worklightsample.android.WorklightSample.Android.NOTIFICATION"} ,
Categories=new[]{Intent.CategoryDefault})]
Format: [package].[app_name from Strings.xml].NOTIFICATION
•Override the lifecycle methods of MainActivity.cs
protected override void OnResume ()
{
base.OnResume(); wlClient.PushService.Foreground = true;
}
protected override void OnPause ()
{
base.OnPause(); wlClient.PushService.Foreground = false;
}
protected override void OnDestroy ()
{
base.OnDestroy(); wlClient.PushService.UnregisterReceivers ();
}

11.
IBM Software Group | Cloud - MobileFirst
Innovation for a smarter planet 11
Push Notifications – lets send a message

Execute the adapter to send a message
C:devworkspacesXtestworklightXtest>mfp invoke
[?] Which adapter do you want to use? PushAdapter
[?] Enter the comma-separated parameters: "worklight","Hello!"
Eventually you will use APIs in the adapter to send notifications from your
server side application

12.
IBM Software Group | Cloud - MobileFirst
Innovation for a smarter planet 12
Push Notifications – the Notification!
If app is in foreground – the Android
activity gets the
notification
If the app is in the background – you see
the notification on the notification bar

13.
IBM Software Group | Cloud - MobileFirst
Innovation for a smarter planet 13
Push Notifications – API

The first step is to create an instance of the WLClient class:
IworklightClient wlClient = Worklight.Xamarin.Android.WorklightClient.CreateInstance (this);
WorklightPushService pushService = wlClient.PushService;

You do all push notification operations from the WorklightPushService
ReadyToSubscribe Event – When connecting to a Worklight Server, the app
attempts to register itself with the GCM server to receive push
notifications. Called when the registration is complete.
InitRegistration() - To initiate the registration sequence.
client.PushService.ReadyToSubscribe += HandleReadyToSubscribe;
client.PushService.InitRegistration();

14.
IBM Software Group | Cloud - MobileFirst
Innovation for a smarter planet 14
Push Notifications – API
Use the RegisterEventSourceNotificationCallback method to register an alias
on a particular event source.
void HandleReadyToSubscribe(object sender, EventArgs a)
{
Console.WriteLine ("We are ready to subscribe to the notification service!!");
client.PushService.RegisterEventSourceNotificationCallback
(pushAlias,"PushAdapter","PushEventSource",new NotificationListener ());
client.PushService.SubscribeToEventSource(pushAlias,new Dictionary<string,string>());
}

15.
IBM Software Group | Cloud - MobileFirst
Innovation for a smarter planet 15
Push Notifications – API
Listener gets the notifications
public class NotificationListener:WorklightPushNotificationListener
{
public void OnMessage(JsonObject NotificationProperties, JsonObject Payload)
{
Console.WriteLine ("Got notification!");
Console.WriteLine (NotificationProperties.ToString ());
}
}

16.
IBM Software Group | Cloud - MobileFirst