Field-specific actions (INFIELD clause)

Using the INFIELD clause of ON ACTION provides automatic action activation when a field gets the focus.

The ON ACTION interaction block of INPUT, CONSTRUCT and INPUT ARRAY (as singular dialogs or sub-dialogs in DIALOG instruction), can be specified with the INFIELD field-name clause. With this clause, the action will only be active when the focus is on one of the fields. The same action name can be used for several fields. 
INPUT ARRAY custarr WITHOUT DEFAULTS FROM sr_cust.*
  ON ACTION zoom INFIELD cust_city
    LET custarr[arr_curr()].cust_city = zoom_city() 
  ON ACTION zoom INFIELD cust_state
    LET custarr[arr_curr()].cust_state = zoom_state() 
END INPUT
Actions defined with the INFIELD field-name clause can be identified with the field name as prefix:
field-name.action-name
You can bind form action views with or without the field name prefix:
-- Form file:
EDIT f1 = customer.cust_name;
BUTTON b1 : cust_name.clear, ... ;    -- field-qualified action
BUTTON b2 : clear, ... ;              -- unqualified action

-- Program code:
ON ACTION clear INFIELD cust_name
   ...
  • Without the field name prefix, the action view is enabled and disabled automatically depending on the current field: The action view is enabled when the corresponding INFIELD field has the focus.
  • When binding the action view with the fully-qualified name including the field name prefix, the action view will always be active, and the focus will jump to the first corresponding field, if the action is fired.
Note:
When using ON ACTION action-name INFIELD field-name for one or several BUTTONEDIT fields, the runtime system implicitly handles the BUTTONEDIT action as a field-qualified action, even if the ACTION attribute is defined without the field name:
BUTTONEDIT f1 = customer.cust_city, ACTION = zoom;
Is equivalent to:
BUTTONEDIT f1 = customer.cust_city, ACTION = cust_city.zoom;
Actions defined in sub-dialogs of the DIALOG instruction get the name of the sub-dialog as prefix. If ON ACTION action-name INFIELD field-name is used in a sub-dialog, the action object name is prefixed with the name of the sub-dialog, followed by the name of the field. The fully-qualified action name will be:
sub-dialog-name.field-name.action-name

When the field-specific action is invoked (for example by a button of the toolbar bound with the fully-qualified action name) and if the field does not have the focus, the runtime system first selects that field before executing the code of the ON ACTION INFIELD block. The field selection forces data validation and AFTER FIELD of the current field, followed by BEFORE FIELD of the target field associated to the action.

It's still possible to enable and disable field-specific action objects by the program using the DIALOG.setActionActive() method. When specifying a fully-qualified action name with the field name prefix, that field-specific action will be enabled or disabled. When disabled by the setActionActive() method, the corresponding action views will always be disabled, even if the field has the focus. If you do not specify a fully-qualified name in the method call, and if several actions are defined with the same action name in different sub-dialogs and/or using the INFIELD clause, the method will identify the action according to the current focus context. For example, if you define ON ACTION zoom INFIELD cust_city and ON ACTION zoom INFIELD cust_addr, when the focus is in cust_city, a call to DIALOG.setActionActive("zoom", FALSE) will disable the action specific to the cust_city field.

Fields can be enabled or disabled dynamically with the DIALOG.setFieldActive() method. If an ON ACTION INFIELD is declared on a field and if you enable/disable the field dynamically, then the field-specific action (and corresponding action views in the form) will be enabled or disabled accordingly.

For action views bound to field actions with qualifiers, the action defaults defined with the corresponding action name will be used to set the attributes with the default values. In other words, the prefix will be ignored. For example, if an action view is defined with the name "cust_addr.check", it will get the action defaults defined for the "check" action.