android 7.0 Notification icon appearing white square

Question

I am using the below snippet to generate notifications in my android app.

private void sendNotification(String contentText, String message) {

    Intent resultIntent = new Intent(this, MainActivity.class);
    resultIntent.putExtra("clear","clear");
    resultIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | 
     Intent.FLAG_ACTIVITY_CLEAR_TASK);

   PendingIntent piResult = PendingIntent.getActivity(this, 0, resultIntent,0);

    NotificationCompat.Builder builder=new NotificationCompat.Builder(this)
            .setSmallIcon(R.drawable.icon)
            .setColor(ContextCompat.getColor(getApplicationContext(),R.color.red))
            .setContentTitle("title")
            .setContentText(message)
            .setAutoCancel(true)
            .setLargeIcon(BitmapFactory.decodeResource(getResources() 
            ,R.drawable.notification))
            .setContentIntent(piResult);

    NotificationCompat.InboxStyle notification = new NotificationCompat.InboxStyle(builder);

    int i;
    for(i=0; i<messageList.size();i++){
        notification.addLine(messageList.get(i));
    }
    notification.setBigContentTitle("title");
    notification.setSummaryText(contentText);

    NotificationManager notificationManager = (NotificationManager)getSystemService(Context.NOTIFICATION_SERVICE);
    notificationManager.notify(NOTIFICATION_ID,notification.build());
}

It works in android 5 and 6 but for android nougat it is not working

Answer 1

From android version lollpop onwards, they have made the changes for the notifications. When you are specifing the small icon, it should be of specific size as mentioned in this link.

The important thing is the image should be transparent and contains only white color.

You can check this question to get the answer

Answer 2

Following the docs from the Android API:

Status bar icons are composed simply of white pixels on a transparent backdrop, with alpha blending used for smooth edges and internal texture where appropriate.

Your whole image but the transparent parts is going to be converted to white (being originally white or having colors).

One solution is to create a silhouette icon with color, by this way you can use the same image in all Android APIs. One example could be this icon:

In lower versions of Android you would see the black face, in the last versions you will see the same face but with white color. That's because of the transparent parts (it seems SO removes the transparency, you can get the original from here) of the image.

Answer 3

According to this blog here

It says that

You’ll note that the icons are not present in the new notifications; instead more room is provided for the labels themselves in the constrained space of the notification shade. However, the notification action icons are still required and continue to be used on older versions of Android and on devices such as Android Wear.

If you’ve been building your notification with NotificationCompat.Builder and the standard styles available to you there, you’ll get the new look and feel by default with no code changes required.