Delete Child Records - Disabled Link Operation

Delete Child Records - Disabled Link Operation

  

When the Studio generates a child instance, it generates it with a BOOLEAN check box, that can be used to select which items are being processed.  Without the check, the "Delete" operation is disabled, but when at least one item is selected, "Delete" becomes enabled.

I am trying to how this logic works, how the platform knows that an item is selected on, so that I can do a similar action with a different button/link.

Can somebody explain or point me the documentation that explains this capability and how it works?

Tx

Found it, finally, it's an ID in the RichWidgets\Link_BulkSelect in the header of the child.

Oh ... and to have multiple Link IDs, you need a comma separated list which is an expression such as this: 

lnkDeleteSelectedEventParticipant.Id + "," + lnkSendEmail.Id