Class with widgets
lazarus / 31-LCL

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rise_nak · 2011-06-26 12:38

Hello!
I'm trying to write a unit with some classes which I'm going to use in
my panel called TitleTanel3. This classes includes GroupBoxes with
some controls. I have the following code:

Code: [Select]unit PanelGadgets;

{$mode objfpc}

interface

uses
  Classes, SysUtils, Forms, StdCtrls;

type
  TTabeleCheckGroup = class(TForm)
    GroupBoxTabTyp: TGroupBox;
    CheckBoxA: TCheckBox;
    CheckBoxB: TCheckBox;
    CheckBoxC: TCheckBox;
  private
    { private declarations }
  public
    { public declarations }
    constructor Create;
  end;

implementation

constructor TTabeleCheckGroup.Create;
begin
  inherited Create(Self);
  GroupBoxTabTyp := TGroupBox.Create(Self);
  CheckBoxA := TCheckBox.Create(Self);
  CheckBoxB := TCheckBox.Create(Self);
  CheckBoxC := TCheckBox.Create(Self);
end;

end.                     

In this unit I want to put this groupboxes, next I create a class in
main code:

Code: [Select]procedure TMainForm.MenuItem15Click(Sender: TObject);  
   // for test code is in menu...
begin
  TabTypDzien := TTabeleCheckGroup.Create();                        //
TabTypDzien is declared in TMainForm class
  TabTypDzien.GroupBoxTabTyp.Parent := TitlePanel3;
end;

And I'm getting SIGSEGV, debugger points to function
TControl.Notification and i don't know wthat is wrong..

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marcov · 2011-06-26 12:53

Set the parent property of the manually created controls to their
parent. (whatever control they are painted on top of)

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rise_nak · 2011-06-26 13:08

Thanks for reply.
I modified constructor TTabeleCheckGroup.Create

Code: [Select]constructor TTabeleCheckGroup.Create(aParent:
TWinControl);
begin
  inherited Create(Self);
  GroupBoxTabTyp := TGroupBox.Create(Self);
  CheckBoxA := TCheckBox.Create(Self);
  CheckBoxB := TCheckBox.Create(Self);
  CheckBoxC := TCheckBox.Create(Self);

  GroupBoxTabTyp.Parent := aParent;
  CheckBoxA.Parent := GroupBoxTabTyp;
  CheckBoxB.Parent := GroupBoxTabTyp;
  CheckBoxC.Parent := GroupBoxTabTyp;
end;              

and in menu now is only:
Code: [Select]TabTypDzien := TTabeleCheckGroup.Create(TitlePanel3);

I didn't know what value set to parent property in GroupBoxTabTyp, so
I made a param aParent, is it ok?
Still is SIGSEGV and debugger shows the same...

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Leledumbo · 2011-06-26 15:11

QuoteAnd I'm getting SIGSEGV, debugger points to function
TControl.Notification and i don't know wthat is wrong..Open the call
stack window, get the first entry pointing to your source code.
Code: [Select]inherited Create(Self);Wait, wait, you're setting Owner
of a form to itself?