Selection screens can be called as follows:
Every call starts selection screen processing.
At the execution of an executable
program via the statement SUBMIT, the standard selection
screen or the selection screen specified in the statement between the events
INITIALIZATION and START-OF-SELECTION is called if it contains at least one input field or one pushbutton.
At the execution of a report transaction, the assigned executable program is started with
SUBMIT, and the selection screen determined for the transaction between the events
INITIALIZATION and START-OF-SELECTION is called.
If at a dialog transaction, the selection screen of the corresponding program is defined as initial screen, then the selection screen is called first at execution of the program via transaction code. However, this selection screen is not treated as the first screen of a screen sequence (see selection screen processing).