Liferay Push for Android

• Setup
• Use
  • Registering a device
  • Receiving push notifications
  • Sending push notifications
  • Unregistering a device

Setup

Add the library as a dependency to your project's build.gradle file:

repositories {
	jcenter()
	mavenCentral()
}

dependencies {
	compile 'com.liferay.mobile:liferay-push:1.0.2'
}

Use

Registering a device

To receive push notifications, your app must register itself to the portal first. On the portal side, each device is tied to a user. Each user can have multiple registered devices. A device is represented by a device token string. Google calls this the registrationId.

Read Android's documentation to learn how to get the registrationId.

It's easy to obtain a registrationId with Liferay Push for Android, you just have to call to the following method:

import com.liferay.mobile.push.Push;

Session session = new SessionImpl("http://localhost:8080", new BasicAuthentication("[email protected]", "test"));

Push.with(session).register(this, SENDER_ID);

The SENDER_ID is the identifier of your GCM project, if you follow the official Android's documentation it should be easy to obtain one.

Since all operations are asynchronous, you can set callbacks to check if the registration succeeded or an error occurred on the server side:

Push.with(session)
	.onSuccess(new Push.OnSuccess() {

		@Override
		public void onSuccess(Object result) {
			System.out.println("Device was registered!");
		}

	})
	.onFailure(new Push.OnFailure() {

		@Override
		public void onFailure(Exception e) {
			System.out.println("Some error occurred!");
		}

	})
	.register(registrationId);

The onSuccess and onFailure callbacks are optional, but it's good practice to implement both. By doing so, your app can persist the device token or tell the user that an error occurred.

Liferay Push for Android is calling the GCM server, retrieving the results and storing your registrationId in the Liferay Portal instance for later use. If you obtain the token manually, you can register the device to the portal by calling the following method:

Push.with(session).register(registrationId);

Now each time the portal wants to send a push notification to the user [email protected], it looks up all registered devices for the user (including the one just registered) and sends the push notification for each registrationId found.

You should note that the Push class is a wrapper for the Mobile SDK generated services. Internally, it calls the Mobile SDK's PushNotificationsDeviceService class. While you can still use PushNotificationsDeviceService directly, using the wrapper class is easier.

Receiving push notifications

Once your device is registered, your app must be able to listen for notifications.

There are several ways to do this:

• If you want to receive global notifications even if the application is not active at the moment you should implement a BroadcastReceiver instance in your app . Android's developer documentation shows you how to do this.

• If you want to execute an action or show a notification only if the application is active, you could register a callback:

Push.with(session).onPushNotification(new Push.OnPushNotification()

	@Override
	public void onPushNotification(JSONObject jsonObject) {
	}

});

This method only works if you have already registered against Liferay Portal using the previous instructions.

Sending push notifications

There are many ways to send push notifications from Liferay Portal. See the Liferay Push documentation for more details. Alternatively, you can send push notifications from your Android app. Just make sure the user has the proper permissions in the portal to send push notifications.

JSONObject notification = new JSONObject();
notification.put("message", "Hello!");

Push.with(session).send(toUserId, notification);

In this code, the push notification is sent to the user specified by toUserId. Upon receiving the notification, the portal looks up all the user's registered devices (both Android and iOS devices) and sends notification as the body of the push notification.

Unregistering a device

If you want to stop receiving push notifications on a device, you can unregister it from from the portal with the following code:

Push.with(session).unregister(registrationId);

Users can only unregister devices they own.