Android Notifications | Notification Channel | Big Picture Style | Android Studio

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The Startup

3 min readFeb 22, 2021

Android Notifications | Notification channel | Big Picture Style | Android Studio

In this tutorial, we’re going to see how to send text and image notifications on android. Before going to create it, first see what notification is?

What is Android Notification?

A notification is a message that Android displays outside your app’s UI to provide the user with reminders, communication from other people, or other timely information from your app. Users can tap the notification to open your app or take an action directly from the notification.

For more Click Here.

Now let’s see how to create it.

Step 1: Design Main XML

In the main XML file create a hook from where we will call our notification channel to show the notification. Here I use a Button to invoke a notification channel.

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/buttonShowNotification"
        android:text="@string/show_notification"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent" /></androidx.constraintlayout.widget.ConstraintLayout>

Step 2: Add Functionality

Set the OnClickListener on the button that we created to invoke the notification channel.

findViewById(R.id.buttonShowNotification).setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        showNotification(); // for notification with Text
    }
});

now create showNotification() function in the MainActivity.java class. This function is for notification with text.

//text Notification
private void showNotification(Bitmap bitmap) {
    
}

create a notification channel and set the notification title, text etc.

//text Notification
private void showNotification(Bitmap bitmap) {
    int noificationId = new Random().nextInt(100);
    String channelId = "notification_channel_3";    NotificationManager notificationManager =
            (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
    Intent intent = new Intent(getApplicationContext(), SecondActivity.class);
    intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
    PendingIntent pendingIntent = PendingIntent.getActivity(getApplicationContext(),
            0,intent,PendingIntent.FLAG_UPDATE_CURRENT);
    NotificationCompat.Builder builder = new NotificationCompat.Builder(
            getApplicationContext(), channelId
    );    builder.setSmallIcon(R.drawable.ic_action_name);
    builder.setDefaults(NotificationCompat.DEFAULT_ALL);
    builder.setContentTitle("Notification 3"); // make suer change the channel for image
    builder.setContentText("Lorem Ipsum is simply dummy text of the printing and typesetting industry");    //notification for image
    builder.setStyle(new NotificationCompat.BigPictureStyle().
            bigPicture(bitmap));    builder.setContentIntent(pendingIntent);
    builder.setAutoCancel(true);
    builder.setPriority(NotificationCompat.PRIORITY_MAX);    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O){
        if (notificationManager != null && notificationManager.
                getNotificationChannel(channelId) == null){            NotificationChannel notificationChannel = new NotificationChannel(
                    channelId, "Notification channel 1",
                    NotificationManager.IMPORTANCE_HIGH
            );            notificationChannel.setDescription("This notification channel is used to notify user");
            notificationChannel.enableVibration(true);
            notificationChannel.enableLights(true);
            notificationManager.createNotificationChannel(notificationChannel);        }
    }    Notification notification = builder.build();
    if (notificationManager != null){
        notificationManager.notify(noificationId, notification);
    }
}

now create a function for notification with image, here I named it as showNotificationWithImage().

//notification with image
@SuppressLint("StaticFieldLeak")
private void showNotificationWithImage(){
    
}

add the functionality for the image notification, also don’t forget to initialize the bitmap in the showNotification() function, because this the main function which creates the notification for us.

//notification with image
@SuppressLint("StaticFieldLeak")
private void showNotificationWithImage(){
    new AsyncTask<String, Void, Bitmap>(){
        @Override
        protected Bitmap doInBackground(String... strings) {            InputStream inputStream;
            try {
                URL url = new URL(strings[0]);
                HttpURLConnection connection = (HttpURLConnection) url.openConnection();
                connection.setDoInput(true);
                connection.connect();
                inputStream = connection.getInputStream();
                return BitmapFactory.decodeStream(inputStream);            }catch (Exception ignored){            }
            return null;
        }
        @Override
        protected void onPostExecute(Bitmap bitmap) {
            showNotification(bitmap);
        }
    }.execute("paste-your-image-link-here");
}