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Appendix I: Initial Values

For those components which add new occurrences to the database it is possible for initial values to be defined in the menu database instead of being hard-coded within the program code. This means that the initial values can be changed very easily.

Initial values are loaded into new occurrences before they are first displayed to the user, but they can be changed at any time.

In order for a component to accept initial values it must contain the following code:

1. It must have a component variable called $INIT_VALUES$.
2. It must have code similar to the following in the <exec> trigger

   params
      string  $params$    : IN
   endparams
   
   getlistitems/id/component $params$     ; copy to component variables
   

3. It must have code similar to the following in the <occurrence gets focus> trigger of the entity in question:-

   if (!$dbocc) & (!$occmod)      ; record is new & unmodified
      call LOAD_INIT_VALUES($init_values$)
      #include STD:FATAL_ERROR
   endif
   

Any initial values that are required must be added to the menu database using transaction MNU_0080M.

When the component is initiated using the standard global proc ACTIVATE_PROC the following will take place:-

• Any initial values will be extracted from the Menu database and placed in an associative list.
• This list will then be added to $$PARAMS as an item with the identity of $INIT_VALUES$, thus producing a list within a list.
• $$PARAMS is the name of an associative list which is passed to the component by ACTIVATE_PROC.
• The code in step (b) above will extract the list of initial values and place it in the component variable called $INIT_VALUES$.
• The code in step (c) above will transfer the contents of the $INIT_VALUES$ list into the component using global proc LOAD_INIT_VALUES.

The following keywords will be converted by proc LOAD_INIT_VALUES at run time:-

• $DATE - will be converted into the current date
• $TIME - will be converted into the current time

Note that it is possible to create another version of the component with an alternative transaction identity so that a different set of initial values can be defined for each Transaction ID.

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