Hiding and showing default action views
If needed, default action views can be hidden or shown.
When an action is rendered with a default action view (for example, by a button on the action frame of a desktop front-end, or in the top action panel on a mobile front-end), it is sometimes required to hide the action button when the operation is not possible and there is not much space on the screen.
Important: Hiding an action will only make the default action view invisible, if
there is a keyboard accelerator associated to the action, it can still fire the action.
Consider disabling the action completely with
setActionActive()
. During a dialog instruction, show or hide an action with the
setActionHidden()
method of the
ui.Dialog
built-in class. This method takes the name of the action (in lowercase
letters) and a boolean expression (FALSE
or TRUE
) as
arguments: BEFORE INPUT
CALL DIALOG.setActionHidden( "zoom", TRUE )
Consider centralizing action visibility control in a setup function specific to the dialog,
passing the
DIALOG
object as the parameter. Centralizing the action
activation defines the rules in a single
location:FUNCTION cust_dialog_setup(d)
DEFINE d ui.Dialog
DEFINE can_modify BOOLEAN
LET can_modify = (cust_rec.is_new OR user_info.is_admin)
CALL d.setActionActive("update", can_modify)
CALL d.setActionHidden("update", IIF(can_modify,0,1))
CALL d.setActionActive("delete", can_modify)
CALL d.setActionHidden("delete", IIF(can_modify,0,1))
...
END FUNCTION
Pay attention to multi-level action definitions inside a
DIALOG
block: Inside a
DIALOG
block, actions must be hidden/shown with the
ui.Dialog.setActionHidden()
method by specifying a simple action
name:DIALOG ATTRIBUTES(UNBUFFERED)
...
BEFORE DIALOG
CALL DIALOG.setActionHidden( "print", TRUE )
...
ON ACTION query
-- query the database and fill the record
...
CALL DIALOG.setActionHidden( "print", (cust_id IS NULL) )
...
END DIALOG