mdi form not closing

[Sam]

Hi,
I have a mdi application in which it is only possible to open one form
at a time. To achieve this I have:

Public Class clsForms
Public Shared frm As Form
End Class

and then when I open a new form:

If Not form Is Nothing Then

If Not clsForms.frm Is Nothing Then
clsForms.frm.Close()
clsForms.frm = Nothing
End If

clsForms.frm = form
clsForms.frm.MdiParent = Me
clsForms.frm.Show()
clsForms.frm.Focus()
End If

It works fine except when I open a pop-up form from the toolbar of the
main form. When i do that, then if I try to open another form after i
closed the pop-up, clsForms.frm is not closed and i end up with having
multiple forms opened.

What is the problem with these pop-up (modal form) ?

 

[ECathell]

First I am curious why you would only want one form open at a time in an
mdi...

If you only want a single instance of the forms to open you are going about
it with a great amount of complexity. All you need is to add this to your
working form:

Private Sub New
End Sub

Private shared m_FrmSomeForm as frmSomeForm
private shared function GetInstance as frmSomeForm
if m_FrmSomeForm is nothing then
m_frmSomeForm=new frmSomeform
end if
return m_frmSomeform
end function

in your MDI:

dim frm as frmSomeForm

frm=frm.getinstance

That way you only have one instance of each form available. Then in the MDI
in your closing event:
e.cancel=false

then when you close your MDI all your child forms will close.

 

[Sam]

Hi,
Thanks for the reply.

That way you only have one instance of each form available

It's not exactely what I want. I want only one form opened at a time,
regardless its type. So if frmFormA is opened and I try to open
frmFormB then frmFormA should be closed.

Is your method going to work?

 

[ECathell]

Works for my needs...I dont know if I understand your needs enough to say
so...

 

[zdrakec]

Dim f as Form
For each f In Me.MDIChildren
f.Close()
Next 'f
'Now comes the code to open your new form

Hope this helps,
zdrakec