General Question About Userforms and Properties

[JBNewsGroup]

Hi,



I am using WORD 2000 and I have a general question about Userforms and
Properties.



Userform-1 displays a custom dialog, Userform-2. Userform-1 has to know
which command button(s) were pressed in Userform-2.



Arguments are "passed" between the forms by property statements. Userform-2
sets properties in Userform-1 by using the CallByName statement. Userform-1
object and property names set in Userform-2 via property statements.



Has anybody had any problems using the above described scenario? That is,
are there problems using property statements in Userforms and using the
CallByName statement?



It does seem to work but I would just like to know if there are any
"gotchas".



Thanks in advance for any help, advice and tips.



Jerry Bodoff

 

[Jezebel]

Two issues: first, CallByName is slow as hell. Second, it's bad programming
practice: a called object shouldn't need any knowledge of its caller.

Much simpler is for Userform2 to set set an internal property, which is read
by UserForm1 --

-- In UserForm1

With new UserForm2
.Show
Select Case .Result
Case 1
...

end with


-- In UserForm2

Private mResult as long 'Module-level variable

Private Sub cmdOK_Click() 'Set the result value in the command button
click events
mResult = 1
End Sub

'Make the result available to the caller
Public Property Get Result() as long
Result = mResult
End Property

 

[JBNewsGroup]

Hi Jezebel,

First off let me say I am sorry about the original message formatting. I
created the question in WORD and cut and paste. When I do this the
formatting gets all screwy.

I have to agree with you that passing properties back and forth is terrible
and not good practice. I do not think your method will work ( unless I am
missing something ). As far as I know Userform1 cannot read Userform2
properties since return to Userform1 is not made until Userform2 unloads.
Therefore, the links are broken and an error message results.

I solved the problem by associating a ClassModule with Form2. Form1 sets
Class Module properties and the form is displayed in the module. Form2
currently has 1 property which is the ClassModule object ("handle"?). That
way Form2 can communicate with the existing ClassModule. I am in the
processing of getting rid of that assignment also. I am working on creating
and passing a UserType to a Form2 method which would use the data to
initialize the form. That way if I have a lot of initial data I only need 1
method instead of a bunch of properties. I really think the ClassModule is
the way to go.

Thanks for your tips and comments. It was appreciated and gave me the
"spark" to create a ClassModule solution.

Jerry Bodoff

 

[Jezebel]

As far as I know Userform1 cannot read Userform2

properties since return to Userform1 is not made until Userform2 unloads.

The process is more subtle than this. It is sufficient for UserForm2 to be
hidden to pass control back to UserForm1. That too is better programming
practice: in classic object-oriented design, an object should never
terminate itself -- that's the responsibility of the caller.

Experiment with code along these lines --

In UserForm1 ------

Dim pForm as UserForm2

Set pForm = new UserForm2
.... at this point you can set and read properties in pForm

pForm.Show

.... at this point also you can set and read properties in pForm

unload pForm
Set pForm = nothing


In UserForm2 ----

Sub cmdClose_Click()
Me.Hide
End Sub

 

[JBNewsGroup]

Hi Jezebel,

I took an approach similar to API's and dialogs. I created a "Dialog
Structure" module which contains the structure Type definition and a Public
definition. Form1 populates the structure by DlgData.Field and then shows
Form2. Form2 does its thing and populates applicable structure fields.
Form2, when done, "closes" itself and therefore Form1 is re-activated. A
proper approach would be to create a Class Module and set properties and let
the Class Module "read" and "write" structure data and start the form.

As far as I know hiding Form2 does not create a return to Form1. A return
is made when Form2 "shuts down". What you suggest is probably possible with
modeless forms. All my forms are modal.

Thanks for the help and discussion. It is always informative to see how
other people approach a problem and one always learns from these
discussions.

Jerry Bodoff

 

[JBNewsGroup]

Hi Jezebel,

I have to apologize. In my previous answer I was unaware that Hide
re-activated the calling form.
As I said we are always learning. To do things properly I am creating a
ClassModule to "read" and "write" the data structure.

Thanks.

Jerry Bodoff

 

[JBNewsGroup]

Hi Jezebel,

Thanks for all your help.

I decided to use the Class Module because I am doing a bit of data
validation in it and I have a few Custom Dialogs that will be processed by
the same module. They all use the same structure and I have about 10
forms that will call it.

Jerry Bodoff