10.17 Action Bar Programming Considerations

The following points are things that you should consider when planning or designing programs to use in conjunction with an action bar:

• Action bar processing programs are generally different to normal entry model programs. They tend to be very small, have one and only one function, and have very little "hard coded" flow of control logic.

• The overriding rule for action bar programming is that the "user is in control". This will ultimately mean that the programs are a lot easier to develop and maintain, but may cause some initial confusion because of the apparent programmer lack of control over what is happening.

• Do not trust / expect other functions to be executed before or after the one you are working on.
  
  Make it robust and able to work standalone.

• Keep the routines simple and short.

• Expect, and allow for, non-procedural flow of control.

• If you are enabling a lot of function keys on DISPLAY and REQUEST commands via the USER_KEYS parameter and coding IF_KEY commands to handle theiruse, consider redesigning your system to be more object orientated and more in the users hands, rather than the designer's hands, with regard to flow of control.