ABAP program that reads and analyzes the data in database tables and sometimes also makes updates.
ABAP report programs have the program type "executable program" and are often linked to a particular logical database.
When you execute an ABAP report program, you can display the resulting output list - also known as a report - on the screen or send it to a printer. You can also save the output list and display it later.
Event in ABAP report determine process flow of a program. The events are triggered depended on the way the output is generated. They begin after event keyword and end when the next event reached.
Event keyword:
INITIALIZATION.
Occurs when report initialized.
We can use it to check user authorization or prepare output for selection screen. Here you can create or determine ranges for your selection data.
AT SELECTION-SCREEN OUTPUT :
Occurs each time selection screen about to generated.
We can use it to modify selection screen, for example hide / unhide parameter.
AT SELECTION-SCREEN.
Occurs each user command in selection screen. we can use it to perform checking rules on user input.
START-OF-SELECTION
Occurs after the standard selection screen has been processed. Select data (to get your data)
data is read in this event.
END-OF-SELECTION
Occurs after start-of-selection. (Finished for selection data)
TOP-OF-PAGE
Occurs when a new page starts.
This portion is use for write report header.
END-OF-PAGE
Occurs when a page ends. Write report footer.
AT LINE-SELECTION
Occurs when the user double-click on report.
AT USER-COMMAND
Occurs when the user push toolbar button.
