Notifications can be created using NotificationUtil. It provides three types of notifications: info, warning and error.

Error notifications stay on the screen until the "Close" button is clicked. Info and warning notifications close automatically after the configured duration in milliseconds, which can be set separately for info and warning. If the duration is set to 0 or lower, each notification of the respective type will have a "Close" button and will stay on the screen until this button is clicked.