Android Create Custom Notifications

Create Custom Layouts

Unity Layout

Open your project in Unity and navigate to Assets/Plugins/Android/OneSignalConfig.plugin/res/

Create a folder called layout

Add two .xml files: notification_small.xml and notification_large.xml using the code samples below. Jump to code samples.

Native and Non-Unity SDKs

Open your project in Android Studio and navigate to app/res/layout and create New > Layout Resource File

Name the file notification_small and click OK.

Repeat this process for another file called notification_large.

Add the following code based on the file name.

Custom Layout Code Samples

You can create 2 default images named small_image and large_image if you want and put them in app/Java/res/drawable. Otherwise remove android:src from the code below.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="64dp"
    android:gravity="center">

    <ImageView
        android:id="@+id/image_view_notification_small"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:scaleType="centerCrop"
        android:src="@drawable/small_image"/>

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="256dp"
    android:gravity="center">
    
    <ImageView
        android:id="@+id/image_view_notification_large"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:scaleType="centerCrop"
        android:src="@drawable/large_image"/>

</LinearLayout>

Setup Notification Service Extension

Create a file called NotificationServiceExtension.java

Unity NotificationServiceExtension

Create a new folder called OneSignalNotificationServiceExtension within your Assets folder.

Add NotificationServiceExtension.java file so it is available like this: Assets/OneSignalNotificationServiceExtension/NotificationServiceExtension

Make sure only Android is selected in the Inspector for this file.

Then add the below Android SDK 3.x.x Java code to the NotificationServiceExtension.java file.

Native and Non-Unity SDKs NotificationServiceExtension

Add this file to app/Java/YOUR_APP

Add the following code based on the version of the OneSignal SDK you are using:

package your.package.name

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.util.Log;

import android.widget.RemoteViews;

import org.json.JSONObject;

import com.onesignal.OSNotification;
import com.onesignal.OSMutableNotification;
import com.onesignal.OSNotificationReceivedEvent;
import com.onesignal.OneSignal.OSRemoteNotificationReceivedHandler;

import java.net.URL;


@SuppressWarnings("unused")
public class NotificationServiceExtension implements OSRemoteNotificationReceivedHandler {

    @Override
    public void remoteNotificationReceived(Context context, OSNotificationReceivedEvent notificationReceivedEvent) {

        // https://developer.android.com/training/notify-user/custom-notification
        // Get the layouts to use in the custom notification
        RemoteViews notificationSmallLayoutView = new RemoteViews(context.getPackageName(), R.layout.notification_small);
        RemoteViews notificationLargeLayoutView = new RemoteViews(context.getPackageName(), R.layout.notification_large);

        OSNotification notification = notificationReceivedEvent.getNotification();
        OSMutableNotification mutableNotification = notification.mutableCopy();

        JSONObject data = notification.getAdditionalData();
        String notification_small_image_url;
        String notification_large_image_url;

        if (data != null) {
            Log.i("OneSignalExample", "Received Notification Data: " + data);
            notification_small_image_url = data.optString("notification_small_image_url", null);
            notification_large_image_url = data.optString("notification_large_image_url", null);
            if (notification_small_image_url != null && notification_large_image_url != null) {
                Log.i("OneSignalExample", "Received Notification Data notification_small_image_url: " + notification_small_image_url);

                notificationSmallLayoutView.setImageViewBitmap(R.id.image_view_notification_small, getBitmapFromURL(notification_small_image_url));
                notificationLargeLayoutView.setImageViewBitmap(R.id.image_view_notification_large, getBitmapFromURL(notification_large_image_url));
                mutableNotification.setExtender(builder -> builder.setCustomContentView(notificationSmallLayoutView)
                        .setCustomBigContentView(notificationLargeLayoutView)
                        //.setStyle(new NotificationCompat.DecoratedCustomViewStyle())//recommended for full background and app title
                );
            }
         }
        // If complete isn't call within a time period of 25 seconds, OneSignal internal logic will show the original notification
        // To omit displaying a notification, pass `null` to complete()
        notificationReceivedEvent.complete(mutableNotification);
    }

    private static Bitmap getBitmapFromURL(String location) {
        try {
            return BitmapFactory.decodeStream(new URL(location).openConnection().getInputStream());
        } catch (Throwable t) {
            Log.i("OneSignalExample", "COULD NOT DOWNLOAD IMAGE");
        }

        return null;
    }

}

package com.onesignal.onesignalsdk;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;

import android.support.v4.app.NotificationCompat;
import com.onesignal.BuildConfig;
import com.onesignal.OSNotificationDisplayedResult;
import com.onesignal.OSNotificationPayload;
import com.onesignal.NotificationExtenderService;
import com.onesignal.OSNotificationReceivedResult;
import java.net.URL;
import android.util.Log;
import android.widget.RemoteViews;
import android.content.Context;
import android.content.Intent;

//import androidx.core.app.NotificationCompat;

import org.json.JSONObject;

public class NotificationServiceExtension extends NotificationExtenderService {
    @Override
    protected boolean onNotificationProcessing(final OSNotificationReceivedResult receivedResult) {

        Log.d("OneSignalExtension", "onNotificationProcessing invoked");

        // https://developer.android.com/training/notify-user/custom-notification
        // Get the layouts to use in the custom notification
        final RemoteViews notificationSmallLayoutView = new RemoteViews(getPackageName(), R.layout.notification_small);
        final RemoteViews notificationLargeLayoutView = new RemoteViews(getPackageName(), R.layout.notification_large);

        final JSONObject data = receivedResult.payload.additionalData;

        OverrideSettings overrideSettings = new OverrideSettings();
        overrideSettings.extender = new NotificationCompat.Extender() {
            @Override
            public NotificationCompat.Builder extend(NotificationCompat.Builder builder) {
                Log.d("OneSignalExtension", "Notification received with payload: " + receivedResult.payload);
                String notification_small_image_url;
                String notification_large_image_url;
                if (data != null){
                    notification_small_image_url = data.optString("notification_small_image_url", null);
                    notification_large_image_url = data.optString("notification_large_image_url", null);
                    if (notification_small_image_url != null && notification_large_image_url != null) {
                        Log.d("OneSignalExtension", "notification_small_image_url: " + notification_small_image_url);
                        Log.d("OneSignalExtension", "notification_large_image_url: " + notification_large_image_url);
                        notificationSmallLayoutView.setImageViewBitmap(R.id.image_view_notification_small, getBitmapFromURL(notification_small_image_url));
                        notificationLargeLayoutView.setImageViewBitmap(R.id.image_view_notification_large, getBitmapFromURL(notification_large_image_url));
                        builder.setCustomContentView(notificationSmallLayoutView);
                        builder.setCustomBigContentView(notificationLargeLayoutView);
                        //.setStyle(new NotificationCompat.DecoratedCustomViewStyle())//recommended for full background and app title
                                
                    }
                }
                return builder;
            }
        };
        OSNotificationDisplayedResult displayedResult = displayNotification(overrideSettings);
        Log.d("OneSignalExtension", "Notification displayed with id: " + displayedResult.androidNotificationId);
        // Return true to stop the notification from displaying.
        return false;
    }

    private static Bitmap getBitmapFromURL(String location) {
        try {
            return BitmapFactory.decodeStream(new URL(location).openConnection().getInputStream());
        } catch (Throwable t) {
            Log.i("OneSignalExample", "COULD NOT DOWNLOAD IMAGE");
        }
        return null;
    }
}

Unity AndroidManifest.xml Setup

Within your Assets/Plugins/Android/AndroidManifest.xml file.

If you don't have this file, check you Build Settings > Android > Player Settings > Publish Settings > Custom Android Manifest is checked.

Add the below <service> code within the <application> ... </application> tags

<service
    android:name="com.onesignal.onesignalsdk.NotificationServiceExtension"
    android:permission="android.permission.BIND_JOB_SERVICE"
    android:exported="false">
    <intent-filter>
    <action android:name="com.onesignal.NotificationServiceExtension" />
    </intent-filter>
</service>

<?xml version="1.0" encoding="utf-8"?>
<manifest
    xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.unity3d.player"
    xmlns:tools="http://schemas.android.com/tools">
    <application>
        <activity android:name="com.unity3d.player.UnityPlayerActivity"
                  android:theme="@style/UnityThemeSelector">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
            <meta-data android:name="unityplayer.UnityActivity" android:value="true" />
        </activity>
<service
    android:name="com.onesignal.onesignalsdk.NotificationServiceExtension"
    android:permission="android.permission.BIND_JOB_SERVICE"
    android:exported="false">
    <intent-filter>
    <action android:name="com.onesignal.NotificationExtender" />
    </intent-filter>
</service>
    </application>
</manifest>

Send the Notification

Within the OneSignal Dashboard, use the "Additional Data" fields to add:

notification_small_image_url and notification_large_image_url as keys with the image url as value.

For example:

notification_small_image_url : https://cdn.pixabay.com/photo/2019/05/29/16/00/retro-4237850_960_720.jpg

notification_large_image_url : https://cdn.pixabay.com/photo/2015/12/23/22/36/minecraft-1106252_960_720.jpg