By their nature, pop-up windows cause more screen writes to be issued than normal full screen panels resulting from DISPLAY or REQUEST commands. This is particularly true of pop-up windows containing browse lists.
To ensure the maximum efficiency of a program that uses POP_UP commands, and to stop any screen "flickering", force LANSA to use DFRWRT(*YES) in the associated IBM i display file by using either of the following declarative commands in the RDML program:
OPEN FILE(*ALL) USE_OPTION(*ONDEMAND)
The significance of the DFRWRT(*YES) option on display files is discussed more fully in the section of this guide on performance considerations.