UserForm usage

[Eric]

I want a generic way to show a UserForm, which I coded as

Public Sub displayForm(form As UserForm, mode As Integer)
Debug.Assert mode = vbModal Or mode = vbModeless
Load form
form.Show mode
End Sub

The method fails,as the UserForm object does not support the Show method. My
question is why does the 'actual' form, which *is* a UserForm, work?
KeyMgtForm.Show vbModeless -----------> works fine

So, is there another object that I can cast the UserForm to that will work?

TIA

 

[keepITcool]

Eric,

Change the datatype for form to Object and it will work.
Public Sub displayForm(form As Object, mode As Integer)

When calling your form you create (and pass) an instance
of the class KeyMgtForm not of the class Userform


--
keepITcool
| www.XLsupport.com | keepITcool chello nl | amsterdam


Eric wrote :

 

[Tom Ogilvy]

How about something like this (add you Mode part)

Public Sub displayForm(form As String)
VBA.UserForms.Add(form).Show
End Sub

Sub ShowForm()
displayForm "MyUserform"

End Sub

 

[Michel Pierron]

Hi Eric,

Public Sub displayForm(form As Object, mode As FormShowConstants)
Load form
form.Show mode
End Sub

MP

 

[Jamie Collins]

When calling your form you create (and pass) an instance
of the class KeyMgtForm not of the class Userform

I'm not sure that's what the OP wants but it raises an interesting
point i.e. that the Userform interface class has no Show method:

Sub demo()
Dim frm1 As VBAProject.UserForm1
Set frm1 = New VBAProject.UserForm1

MsgBox TypeOf frm1 Is VBAProject.UserForm1
MsgBox TypeOf frm1 Is MSForms.UserForm

' UserForm1 has a Show method
frm1.Show vbModeless
frm1.Hide

Dim frm As MSForms.UserForm
Set frm = frm1

MsgBox TypeOf frm Is VBAProject.UserForm1
MsgBox TypeOf frm Is MSForms.UserForm

' Userform interface class
' does not have a Show method:
' frm.Show vbModeless ' <<< error

Load frm
With VBA.UserForms
Set frm1 = .Item(.Count - 1)
End With
frm1.Show vbModeless
End Sub

The UserForm interface has no Show method and that is why the OP's code
raises a run-time error. Using As Object as a parameter, when As
(interface) is available, requires additional validation code (among
other reasons), so how about this variation on Tom's suggestion:

Public Sub displayForm( _
ByVal form As UserForm, _
Optional ByVal mode As FormShowConstants = vbModal _
)
' (code to validate mode)
VBA.UserForms.Add(TypeName(form)).Show mode
End Sub

Jamie.

--

 

[keepITcool]

Hi Jamie

I'm not sure your code is very efficient: Passing the form byval
creates 2 instances of the interface class (both in the caller and in
the callee). Check vba.userforms before the line: VBA.userforms.add

Since you're not really using the interface class object, I think
passing a string is more logical. Plus I think it should be wrapped in
a function

My function needs additional handling for calling existing forms
in different modes.. but alas.


Sub demoS()
Dim ufs(2) As Object

Set ufs(0) = showform("UserForm1", vbModeless)
Set ufs(1) = showform("UserForm1", vbModeless)
Set ufs(2) = showform("UserForm1", vbModeless, True)
ufs(0).Left = 100
ufs(1).Left = 400
ufs(0).Caption = "ZERO"
ufs(1).Caption = "UNO"
ufs(2).caption = "DUE"

End Sub

Function showform(formclass As String, _
Optional ByVal mode As FormShowConstants = vbModal, _
Optional ByVal useExisting As Boolean) As Object

Dim uf As Object

If useExisting Then
For Each uf In VBA.UserForms
If TypeName(uf) = formclass Then Exit For
Next
End If
On Error GoTo theEND
If ObjPtr(uf) Then
Set showform = uf
Else
Set showform = VBA.UserForms.Add(formclass)
End If

showform.Show mode
theEND:
End Function


--
keepITcool
| www.XLsupport.com | keepITcool chello nl | amsterdam


Jamie Collins wrote :

 

[Jamie Collins]

I'm not sure your code is very efficient: Passing the form byval
creates 2 instances of the interface class (both in the caller and in
the callee).

Worse the unreferenced object created in the caller doesn't get
released until the project ends e.g. press the reset button in the VBE
or re-using the global instance of userform1 :-( Of course, passing
ByRef makes no difference.

Since you're not really using the interface class object, I think
passing a string is more logical.

I guess I'd reluctantly go for the latebound call using Object.
However, I think if the OP's has a genuine need for a generic routine
to show a userform (rather than merely posing an interesting
theoretical question), I would expect them to prefer the classname as
a string in the Userforms.Add method. I can't quite see it - element
names stored in a database, perhaps?

Now, can someone tell me why the Show method isn't in the interface...
Jamie.

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