When expanded, a notification may display up to three actions on a strip at the bottom.
Starting in Android N, actions are shown without icons in order to accommodate more text. An icon should still be provided because devices with earlier versions of the OS continue to rely on it, as will Android Wear and Android Auto devices.
You can add up to 3 actions in your notification by passing the following values as custom data fields with your notification:
Payload field key: actionBtns
Type: Array
Value:
"actionBtns":[ {"title":"reply", "action":"https://pushbots.com", "icon":"ic_action_download"}, {"title":"archive", "action":"com.pushbots.abdullahdiaa.pushbotsapp.SettingsActivity", "icon":"ic_action_settings"} ]