On_Select userexit in the widget-menu/button-area or On_Event userexit in the widget state.
The userexit adds the following fields to the end of a list:
The userexit does not resize the widget for displaying the system fields. If you want to see these columns, you will have to navigate to the right in the widget or maximize the widget size.
Example:
In DataView itself the keyboard event of the key combination [Ctrl+A] in widget state is realized with this userexit.