Example: (custmain.4gl)

Calls to the setActionActive method from the ui.Dialog class have been added to custmain.4gl to disable and enable menu actions appropriately to give the user visual cues. An additional ON ACTION statement exits the menu if the user selects .

Module custmain.4gl:

01
02 MAIN
03 DEFINE query_ok SMALLINT
04
05 DEFER INTERRUPT
06 CONNECT TO "custdemo"
07 CLOSE WINDOW SCREEN
08 CALL ui.Interface.setImage("smiley")
09 OPEN WINDOW w1 WITH FORM "custform"
10
11 LET query_ok = FALSE
12
13 MENU 
14   BEFORE MENU
15     CALL DIALOG.setActionActive("next",0)
16     CALL DIALOG.setActionActive("previous",0)
17   ON ACTION find
18     CALL DIALOG.setActionActive("next",0)
19     CALL DIALOG.setActionActive("previous",0)
20     CALL query_cust() RETURNING query_ok 
21     IF (query_ok) THEN
22       CALL DIALOG.setActionActive("next",1)
23       CALL DIALOG.setActionActive("previous",1)
24     END IF
25   ON ACTION next 
26      CALL fetch_rel_cust(1)
27   ON ACTION previous 
28     CALL fetch_rel_cust(-1)
29   ON ACTION quit 
30     EXIT MENU
31   ON ACTION close 
32     EXIT MENU
33 END MENU
34 
35 CLOSE WINDOW w1
36 
37 DISCONNECT CURRENT
38 
39 END MAIN

Note:

Line 08 The icon for the application windows is set to the "exit" image.
Lines 15, 16 Before the menu is first displayed, the next and previous actions are disabled.
Lines 18, 19 Before the query_cust function is executed the next and previous actions are disabled
Lines 21 thru 24If the query was successful the next and previous actions are enabled.
Line 31 The close action is included in the menu, although an action view won't display on the form. If the user clicks the in the top right of the window, the action on line 32, EXIT MENU, will be taken.