[lazarus] Win32 bug: tcontrol's painting themselves in tgroupboxes

[Micha Nelissen]

Mattias Gaertner wrote:

> On Sun, 31 Aug 2003 20:59:49 +0200
> Micha Nelissen <M.Nelissen at student.tue.nl> wrote:
> 
> 
>>Mattias Gaertner wrote:
>>
>>
>>>On Sun, 31 Aug 2003 18:54:50 +0200
>>>Mattias Gaertner <nc-gaertnma at netcologne.de> wrote:
>>>
>>>
>>>
>>>>On Sun, 31 Aug 2003 16:58:18 +0200
>>>>Micha Nelissen <M.Nelissen at student.tue.nl> wrote:
>>>>
>>>>
>>>>
>>>>>Hi,
>>>>>
>>>>>The problem is the following: if a tcontrol paints itself to it's
>>>
>>>parent>>
>>>
>>>>>DC, and the parent's clientrect is different than the origin, the 
>>>>>tcontrol's will paint themselves to the wrong position, namely the 
>>>>>parent.topleft, not the topleft of the clientrect. This happens with 
>>>>>TColorButton's in TGroupboxes for example. How do we solve this?
>>>>>
>>>>>FYI: Delphi has not solved this, a control at position (0,0) in a 
>>>>>tgroupbox is painted on top of the caption, while we want it in the 
>>>>>clientrect.
>>>>
>>>>Right.
>>>>An additional problem is, that the gtk paints before and the win32 paint
>>>>during message handling and they both uses different DC origins. There
>>>
>>>are>plenty of possibilities, where the origin can be moved to fix this. I
>>>will>also look into this ...
>>>
>>>
>>>Maybe I find a solution.
>>
>>Hmm, not quite :(. The groupbox caption is not drawn anymore. It seems 
>>the window rect has stayed in the same position, but the whole box has 
>>moved up. Difference in top position of tcontrols and twincontrols has 
>>stayed the same.
> 
> 
> Hmm. It works for me. I have to test more examples...

Well, what did you try? Can you try attached example? It is a modified 
groupbox example.

> BTW, GetCLientBounds was not implemented and so I started it. It is not
> complete yet. 

To what extent can it be blamed?

Regards,

Micha.


{  $Id: groupbox.pp,v 1.6 2003/08/12 16:04:22 mattias Exp $  }
{
 /***************************************************************************


                   Initial Revision  : Sun Mar 28 23:15:32 CST 1999


 ***************************************************************************/

 ***************************************************************************
 *                                                                         *
 *   This source is free software; you can redistribute it and/or modify   *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This code is distributed in the hope that it will be useful, but      *
 *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU     *
 *   General Public License for more details.                              *
 *                                                                         *
 *   A copy of the GNU General Public License is available on the World    *
 *   Wide Web at <http://www.gnu.org/copyleft/gpl.html>. You can also      *
 *   obtain it by writing to the Free Software Foundation,                 *
 *   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.        *
 *                                                                         *
 ***************************************************************************
}
program GroupBox;

{$mode objfpc}{$H+}

uses
  Interfaces, Classes, StdCtrls, Forms, Buttons, Menus, ComCtrls, SysUtils,
  Dialogs;

type
  TForm1 = class(TFORM)
  public
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    Button4: TButton;
    grpTst : TGroupBox;
    mnuFile: TMainMenu;
    itmFileQuit: TMenuItem;
    CheckBox1: TCheckBox;
    clrBtn: TColorButton;
    constructor Create(AOwner: TComponent); override;
    procedure LoadMainMenu;
    procedure mnuQuitClicked(Sender : TObject);
  protected
    procedure Button1CLick(Sender : TObject);
    procedure Button2CLick(Sender : TObject);
    procedure Button3CLick(Sender : TObject);
    procedure Button4CLick(Sender : TObject);
  end;

var Form1 : TForm1;

constructor TForm1.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
  Caption := 'Groubox Demo v0.1';
  LoadMainMenu;
end;

procedure TForm1.Button1Click(Sender : TObject);
Begin
  if assigned (grpTst) then grpTst.Height := grpTst.Height + 10;
End;

procedure TForm1.Button2Click(Sender : TObject);
Begin
  if assigned (grpTst) then begin
    grpTst.Width := grpTst.Width + 10;
    grpTst.Show;
  end;
End;

procedure TForm1.Button3Click(Sender : TObject);
Begin
  if assigned (grpTst) then begin
    grpTst.Show;
  end;
End;

procedure TForm1.Button4Click(Sender : TObject);
Begin
  if assigned (grpTst) then begin
    grpTst.Hide;
  end;
End;

{------------------------------------------------------------------------------}

{------------------------------------------------------------------------------}
procedure TForm1.LoadMainMenu;
begin
  { set the height and width }
  Height := 350;
  Width := 700;

  { Create a groupbox }
  grpTst := TGroupBox.Create(Self);
  with grpTst do begin
    Name:='grpTst';
    Parent := self;
    top := 70;
    left := 10;
    Height := 200;
    Width := 300;
    Caption := 'Groupbox with 2 Buttons';
  end;

  clrBtn := TColorButton.Create(Self);
  with clrBtn do begin
    Parent := grpTst;
    SetBounds(10,10,25,25);
  end;

  CheckBox1 := TCheckBox.Create(Self);
  with CheckBox1 do begin
    Parent := grpTst;
    SetBounds(40,10,100,20);
    Caption := 'checkbox';
  end;

  mnuFile := TMainMenu.Create(Self);

  itmFileQuit := TMenuItem.Create(Self);
  itmFileQuit.Caption := 'Quit';
  itmFileQuit.OnClick := @mnuQuitClicked;
  mnuFile.Items.Add(itmFileQuit);
end;

{------------------------------------------------------------------------------}
procedure TForm1.mnuQuitClicked(Sender : TObject);
begin
  Close;
end;
{------------------------------------------------------------------------------}

begin
  Application.Initialize; { calls InitProcedure which starts up GTK }
  Application.CreateForm(TForm1, Form1);
  Application.Run;
end.