Dynamic multiple dialog

Dynamic dialogs allows you to create the equivalent of a DIALOG procedural dialog.

Steps to implement a dynamic multiple dialog

The order in which dialog methods are called defines the structure of the dynamic multiple dialog.

To build a dynamic multiple dialog:
  1. Create the multiple dialog with createMultipleDialog().
  2. Add global dialog triggers with addTrigger().
  3. Define the fields for a sub-dialog with a DYNAMIC ARRAY OF RECORD with name and type members.
  4. Add the sub-dialog with one of the following methods:
  5. Add sub-dialog triggers with addTrigger(). When calling this method after a sub-dialog item is added, it will create the trigger in the sub-dialog context.
  6. Implement the WHILE loop using the nextEvent() method, as for a simple dynamic dialog. However, sub-dialog triggers must be identified with the sub-dialog name.

Identifying global and sub-dialog actions

Sub-dialog actions are added with addTrigger("ON ACTION action-name") in the context of a sub-dialog definition, after calling a method such as addDisplayArrayTo().

In the event loop, the nextEvent() method returns sub-dialog actions events with the sub-dialog name prefix, using the "ON ACTION sub-dialog-name.action-name" text form:

...
CALL d.addDisplayArrayTo(fields, "sr_cust")
CALL d.addTrigger("ON ACTION refresh")
...
WHILE (t := d.nextEvent()) IS NOT NULL
  CASE t
     ...
     WHEN "ON ACTION sr_cust.refresh"
       ...

Multiple dialog initialization and termination triggers

As in a static multiple dialog, the BEFORE DIALOG and AFTER DIALOG events indicate respectively the initialization and termination of the dynamic multiple dialog:
WHILE (t := d.nextEvent()) IS NOT NULL
  CASE t
     ...
     WHEN "BEFORE DIALOG"
       ...
     WHEN "AFTER DIALOG"
       ...

Identifying sub-dialog triggers

Sub-dialog triggers such as BEFORE DISPLAY, BEFORE INPUT can be identified in the event loop with the sub-dialog identifier. The nextEvent() method returns the event text in the form "trigger-name sub-dialog-name".

For example, when you define the DISPLAY ARRAY-style sub-dialog with the screen record name "sr_cust", the trigger "BEFORE DISPLAY sr_cust" will be generated when the sr_cust list gets the focus (as in a static DIALOG / END DIALOG multiple dialog block): 
...
CALL d.addDisplayArrayTo(fields, "sc_cust")
...
CALL d.addDisplayArrayTo(fields, "sc_prod")
...
WHILE (t := d.nextEvent()) IS NOT NULL
  CASE t
     ...
     WHEN "BEFORE DISPLAY sc_cust"
       ...
     WHEN "AFTER DISPLAY sc_cust"
       ...
     WHEN "BEFORE DISPLAY sc_prod"
       ...
     WHEN "AFTER DISPLAY sc_prod"
       ...

Note that the nextEvent() method returns only basic information about the event that occurred. For example, "BEFORE FIELD" events contain only the field name without a prefix that allows to identify the sub-dialog. To get detailed information about the last event, use the ui.Dialog.getEventDescription() method.

Example

This example defines a dynamic multiple dialog with a DISPLAY ARRAY and CONSTRUCT BY NAME sub-dialogs, and adds ON ACTION triggers at global and sub-dialog levels:

TYPE t_fields DYNAMIC ARRAY OF RECORD
                name STRING,
                type STRING
              END RECORD
DEFINE d ui.Dialog,
       list_fields t_fields,
       qbe_fields t_fields
...
OPEN WINDOW w1 WITH FORM "myform"
...
LET d = ui.Dialog.createMultipleDialog()
-- add global triggers
CALL d.addTrigger("ON ACTION accept")
CALL d.addTrigger("ON ACTION cancel")
...
-- Add a DISPLAY ARRAY sub-dialog with name "sr_cust" (screen array)
CALL d.addDisplayArrayTo(list_fields, "sr_cust")
CALL d.addTrigger("ON ACTION refresh")
...
-- Add CONSTRUCT BY NAME sub-dialog with name "qr_cust"
CALL d.addConstructByName(qbe_fields, "qr_cust")
CALL d.addTrigger("ON ACTION query")
...
WHILE (t := d.nextEvent()) IS NOT NULL
  CASE t
     ...
     WHEN "ON ACTION sr_cust.refresh"
       CALL refresh_list(d)
     ...
     WHEN "ON ACTION qr_cust.query"
       CALL exec_query(d)
     ...
     WHEN "ON ACTION accept"
       CALL d.accept()
     WHEN "ON ACTION close"
       EXIT WHILE
     WHEN "AFTER DIALOG" -- after d.accept()
       EXIT WHILE
  END CASE
END WHILE
CALL d.close()
LET d = NULL
CLOSE WINDOW w1