Adds the selection to the list of selections associated with this input. This method is not valid within the commandCreated event but must be used later in the command lifetime. If you want to pre-populate the selection when the command is starting, you can use this method in the activate method of the Command. It's also valid to use in other events once the command is running, such as the validateInputs event.
Defined in namespace "adsk::core" and the header file is <Core/UserInterface/SelectionCommandInput.h>.