6.13.8 Asking User to Confirm the Closing of a Form
If you want to give the user the option of confirming whether a form should be closed, use the CloseFormQuery method and the CloseQuery event.
Our example has two forms: the main form and a dialog which is displayed when the form is about to be closed. The main form has two buttons, OK and Cancel.
The Cancel button closes the form using the CloseFormQuery method:
Invoke #Com_Owner.CloseFormQuery
In addition to the buttons, the form includes the Dialog form.
The Dialog form has three buttons:
All the three buttons have a Click event routine which closes the form:
EVTROUTINE HANDLING(#BTN_CLOSE.Click)
Invoke #Com_Owner.CloseForm
ENDROUTINE
EVTROUTINE HANDLING(#BTN_CANCEL.Click)
Invoke #Com_Owner.CloseForm
ENDROUTINE
EVTROUTINE HANDLING(#BTN_MIN.Click)
Invoke #Com_Owner.CloseForm
ENDROUTINE
In addition, they have their ModalResult values set as follows:
|
|
#BTN_CLOSE |
Cancel |
|
|
#BTN_CANCEL |
No |
|
|
#BTN_MIN |
OK |
In addition to the Cancel button event routine, the main form has an event routine for the CloseQuery event. This routine invokes the Dialog form and then receives its ModalResult when the Dialog form is closed. It then tests for the value of the returned ModalResult and performs actions accordingly.
Note that whether the Closing of the form is continued depends on the value of the #Option field which is used for the Continue parameter.
EvtRoutine Handling(#Com_Owner.CloseQuery) Continue(#Option)
Invoke #Dialog.ShowModalForm
Define #QResult Reffld(#Std_Texts)
Change #QResult #Dialog.modalResult
Case #QResult
When '= No'
Invoke #Com_Owner.RestoreForm
Set #Option Value(FALSE)
When '= OK'
Invoke #Com_Owner.MinimizeForm
Set #Option Value(FALSE)
OtherWise
Set #Option Value(TRUE)
EndCase
EndRoutine
The case statement restores the main form if the ModalResult value returned from the Dialog form is No (assigned to the Cancel button) and minimizes the main form if the value returned is OK (assigned to the Minimize button). In both cases the Continue parameter is set to False. If any other ModalResult value is returned, the form is closed.
