cannot resolve method setGroup <p>I wanted to assign a notification to a group with <code>setGroup()</code> for stacking notifications and summarising them. </p> <p>Like <a href="https://developer.android.com/training/wearables/notifications/stacks.html" rel="nofollow">HERE</a></p> <pre><code>final static String GROUP_KEY_SAPPHIRE = "group_key_emails"; NotificationCompat.Builder oneBuilder = new NotificationCompat.Builder(this); oneBuilder.setSmallIcon(R.drawable.warning_icon) .setContentTitle("Warning: ") .setContentText(message) .setPriority(0x00000002) .setLights(Color.GREEN, 500, 500) .setGroup(GROUP_KEY_SAPPHIRE) .addAction (R.drawable.ic_action_accept_dark, getString(R.string.ok), warningPendingIntent); NotificationManager oneNotificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE); oneNotificationManager.notify(NOTIFICATION_ID, oneBuilder.build()); editText.setText(""); </code></pre> <p>But I always got the response that the method setGroup couldn't be resolved. I've imported the <strong>.v4.support library</strong>.</p> <p>Thanks in advance</p>