You can do the following...
1. Instead of using Action := caFree, use "Release" this will not
raise AV.
2. To make sure you have single child instance, please use the
following code in your child form
{ Public declarations }
constructor Create(AOwner: TComponent); override;
destructor Destroy; override;
...
implementation
constructor TForm1.Create(AOwner: TComponent);
begin
if (Form1 <> nil) then
begin
Form1Show;
Abort;
end else
Form1 := inherited Create(AOwner);
end;
destructor TForm1.Destroy;
begin
if (Form1= Self) then Form1 := nil;
inherited;
end;
Hope this helps,
Kiran Kurapaty
________________________________
From: advanced_delphi@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of Johan Muller
Sent: 29 June 2007 07:04
To: advanced_delphi@yahoogroups.com
Subject: [advanced_delphi] MDI Applications
Hi i'm new to MDI Applications and I have two questions.
1. I have a button on my childform to close the form. I know about the
Action := caFree in the onClose event to close the form, but I'm looking
for a way to also close the form when I click on the close button in my
childform. I tried the normal form.close but I get an Access Violation.
2. I want to make sure that my users can only open one instance of a
specific childform. In other word some way of checking if the childform
is already open and if it is, it must not open the form again.
If anyone can help I will appreciate it very much
Thanks,
JJ.
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