The user interacted with one of the controls within the notification. This currently means a button click, but other control types will be added in future releases.
The action was triggered programmatically by an application.
Not currently supported - will be implemented in a future release
The user clicked the body of the notification itself. Any clicks of the notification that don't hit a control
or the close button will fire an event with the 'select' action trigger.
Lists the different triggers that can raise an action. Each action that is raised will result in a
notification-actionevent, which can be captured by the application that created the notification.