Modifying Screens Dynamically 

The attributes of screen elements are set statically in the Screen Painter when you define them. However, it is possible to override some of these attributes in ABAP programs with the help of a special internal table.

The R/3 System contains a function called field selection, which allows you to change the attributes of screens dynamically.

It is also possible to set the cursor on a screen to a particular position dynamically from your program.

Setting Attributes Dynamically

The Field Selection Function

Setting the Cursor Position