[HeDiBo]

Sometimes a ShowPopupForm will give an exception:

This is the trace leading to the exception:

My procedure:

procedure TfrCompetition.btnAddPoolClick(Sender: TObject);
var
   p: TPoint;
begin
   btnAddPool.Enabled := False;
   if not Assigned(frmAddPool2Comp) then frmAddPool2Comp := TfrmAddPool2Comp.Create(Self);
   p := btnAddPool.ClientToScreen(Point(0, btnAddPool.Height));
   ShowPopupForm(frmAddPool2Comp, p);  // Will throw exception
end;

acPopupController: lines 130-134
procedure ShowPopupForm(AForm: TForm; ALeftTop: TPoint; Animated: boolean = True);
begin
  GetIntController.KillAllForms(AForm);   // <<< Throws exception
  acIntController.ShowFormPos(AForm, ALeftTop, Animated);
end;

acPopupController: lines 137-146:
procedure TsPopupController.KillAllForms(ExceptChild: TForm);
var
  i: integer;
  ParentForm: TForm;
  ClosedAll: boolean;
begin
  if ExceptChild <> nil then
    ParentForm := TForm(GetOwnerForm(ExceptChild.Owner))  // <<< Throws exception
  else
    ParentForm := nil;

sVclUtils: lines 3146-3175:
function GetOwnerForm(const Component: TComponent): TCustomForm;
var
  c: TComponent;
begin
  Result := nil;
  c := Component;             // <<< Component is an invalid address ($80808080)
  while Assigned(c) and not (c is TCustomForm) do
    c := c.Owner;

  if c is TCustomForm then
    Result := TCustomForm(c);
end;

Apparently the ExceptChild.Owner may be freed without being nil.

[Support]

HeDiBo wrote:

Apparently the ExceptChild.Owner may be freed without being nil.

Yes, looks like that. But I can’t imagine when owner may be destroyed here.
Is it possible to make a test-app with such problem?

[HeDiBo]

Support wrote:

Yes, looks like that. But I can’t imagine when owner may be destroyed here.
Is it possible to make a test-app with such problem?

I’ll have another look at it tomorrow.

[HeDiBo]

Found the bug.
My project consists of a large number of TFrames, placed on pages of a giant TsPageControl. Some of these frames may show pupup windows. If these windows close, they set the Action to caFree and set there form variable to nil.
One of the popup windows did not set the form variable to nil. Causing the problem.
I still think it’s a bug in AC. Setting Action to caFree should be enough.

[Support]

Hello!
The package doesn’t use these variables, they are not accessible in units of the package.
If I understand you correctly.
Can you help me to repeat the error, please? Is it possible in a separate demo-app?

[HeDiBo]

Sorry Serge,

It was my own stupid mistake 😳

[HeDiBo]

This one can be closed.
Previously I could close topics myself. Is there some way now to do that? That is, can I add the tag [Resolved] myself?

[Support]

Topic may be closed by author or by admin in the his first message.

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[HeDiBo]

I don’t see this menu line in my first post.
It only says:

October 13, 2019 at 1:49 pm REPLY | QUOTE #62379

• This reply was modified 4 years, 11 months ago by HeDiBo.
• This reply was modified 4 years, 11 months ago by HeDiBo.

[HeDiBo]

Any progress on letting authors close their own topics?

[Support]

No, sorry. Can’t find how to make it in the WP still.

[Author]

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