ABAP_to_the_Future

Designing a Report Interface 10.2
Setting Up Event Handling
Listing 10.6 sets the handlers, which me ans that it defines how user commands
are handled in the program.
set_handlers( ).
METHOD set_handlers.
mo_events = mo_alv_grid->get_event( ).
SET HANDLER handle_link_click
FOR mo_events.
SET HANDLER handle_user_command FOR mo_events.
ENDMETHOD.
Listing 10.6 Custom ALV Object: SET_HANDLERS Method
Forging the link between the events that are raised by the SALV objects is quite
complicated. The main SALV class contains an attribute within it (CL_SALV_EVENTS_
TABLE) that raises an event ( RAISE_LINK_CLICK) when a user clicks on a hotspot.
You need the code in Listing 10.6 to tell your newly created SALV object that the
HANDLE_LINK_CLICK method in your custom SALV class is going to respond to that
event. That declaration does half the job; the other step you need to do is to make
sure that the definition of the even t handler method links the event from CL_
SALV_EVENTS_TABLE to your custom event handling method. In SE24, select the
method HANDLE_LINK_CLICK of your custom cl ass and click on the Detail View
icon at the top of the list of methods. The result can be seen in Figure 10.5.
Setting up such a definition in the class gives the method the potential to be used
as an event handler, but it’s not actually used until a SET_HANDLER command is
used at runtime to subscribe to an event; that is, you activate the linkage between
a specific instance of the class that rais es the event and a specific instance of the
class that is to handle the event.
Now you’ve handled the case in which the user has clicked a hotspot, such as
clicking a monster number to display the monster master record. The other case
you have to deal with is one in which you’ve added your own buttons to the top
of the screen (the steps for doing this are explained in Section 10.3) and the user
has clicked one of them. Naturally, if the user clicks one of the standard buttons,
then the SALV class deals with that situation itself.
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