dlgEvent_record_OnChange_fieldName
Function called after user input has changed a value in a record field.
Syntax
PUBLIC FUNCTION dlgEvent_record_OnChange_fieldName(
dlg ui.DIALOG,
uiMode SMALLINT,
dlgCtrlInstruction libdbappEvents.DlgCtrlInstruction_Type)
RETURNS (libdbappEvents.DlgCtrlInstruction_Type)
If fieldName is a database field, the
table.column
syntax is replaced by
table_column
.
The function parameters are:
dlg
. This is aui.DIALOG
object referencing the current dialog. The dialog can implement anINPUT
,INPUT ARRAY
,DISPLAY ARRAY
,MENU
, orCONSTRUCT
. For more information, see The Dialog class in Genero Business Development Language User Guide.uiMode
. This is an integer value defining the current mode or state in relation to user action in the dialog, form, or application. Modes are defined as constants in the libdbappFormUI file in the libdbapp library.Table 1. UI modes Description Applies to ... Constant Value Display DISPLAY ARRAY
C_MODE_DISPLAY 1 Modify INPUT \ INPUT ARRAY
C_MODE_MODIFY 2 Add INPUT \ INPUT ARRAY
C_MODE_ADD 3 Search CONSTRUCT
C_MODE_SEARCH 4 Empty MENU
C_MODE_EMPTY 5 Exit form The form C_MODE_EXIT_FORM 6 Exit app The app C_MODE_EXIT_APP 7 Undefined All (array, form, or app) C_MODE_UNDEFINED 0 dlgCtrlInstruction
is a libdbappEvents.DlgCtrlInstruction_Type defining the dialog control instruction. Instructions available in the function are shown in the table.Table 2. Dialog control instructions Description Constant Value Accept dialog ACCEPT_DIALOG
1 Continue dialog CONTINUE_DIALOG
2 Exit dialog EXIT_DIALOG
3
The function returns a dialog control instruction value defined by libdbappEvents.DlgCtrlInstruction_Type
.
Usage
When you select the On Change property for the creation of the event, a function shell is created. Enter your code in the function.
Use this function detect when a field has been changed by user input in an
INPUT
, INPUT ARRAY
, or
CONSTRUCT
dialog. For EDIT
,
TEXTEDIT
, and BUTTONEDIT
fields, this function
is called after the user moves to a new field. For other fields (such as
CHECKBOX
or COMBOBOX
), it is called
immediately after the user changes the value.
Example: On Change
This example uses the On Change code event for a record field in the Account form of the OfficeStore demo.
The function verifies whether the category.catname
field was left
blank. If the value is NULL
, an error message is raised and the
focus is returned to the field so the user may enter a value.
PUBLIC FUNCTION dlgEvent_recAccount_OnChange_category_catname(
dlg ui.Dialog, uiMode SMALLINT, dlgCtrlInstruction libdbappEvents.DlgCtrlInstruction_Type)
RETURNS(libdbappEvents.DlgCtrlInstruction_Type)
DISPLAY "dlgEvent_recAccount_OnChange_category_catname (Field scope) is raised for ", dlg.getCurrentItem()
IF (uiMode = C_MODE_ADD OR uiMode = C_MODE_MODIFY)
AND dlg.getFieldValue(dlg.getCurrentItem()) IS NULL THEN
ERROR " Favorite category is needed "
CALL dlg.nextField(dlg.getCurrentItem())
END IF
DISPLAY "dlgEvent_recAccount_OnChange_category_catname (Field scope) is exited"
RETURN dlgCtrlInstruction
END FUNCTION