fpGUI

<h2 id="history">History</h2>
<p>The first version of fpGUI was written by Sebastian Günther back in 2000. The project was then abandoned in 2002. fpGUI was a successor to an earlier OO GTK wrapper, fpGTK, and was pretty much a fresh start to allow multiple (backend) widgetsets, most notably win32. The toolkit was used for some internal FPC tooling (e.g. the fpdoc editor), but there were still a lot of open issues before the toolkit could be truly useful and used in real life applications by end-users.  Most of these tools where migrated to the maturing <a href="/facts/Lazarus_(IDE)/6Il32HeV">Lazarus</a> in the 2004-2006 timeframe.
</p><p>Graeme Geldenhuys revived the toolkit in mid-2006 where Sebastian left off. He continued developing the toolkit for the next year. Merging three sub-projects (fpGFX, fpIMG and fpGUI) into a single project fpGUI. Graeme extended the number of components and amount of backend graphics layer, and improved the overall toolkit. The supported platforms at that stage was <a href="/facts/Linux/9FvCKSTq">Linux</a> and <a href="/facts/FreeBSD/RKsFTm7F">FreeBSD</a> via <a href="/facts/X11/ac2vRIQL">X11</a> and Microsoft Windows via GDI.  After a few months Felipe Monteiro de Carvalho joined the development team adding support for Windows Mobile devices and extending the graphics support and design. Felipe also started working on Mac OS X support via Carbon.
</p><p>At the beginning of June 2007 Graeme found some major design issues in the source base. This prevented fpGUI from being truly useful in real applications.  After numerous prototypes the fpGUI project was completely rewritten.  Past experience helped a lot and new design ideas were implemented. The code base ended up being much simpler with a cleaner design. One of the major changes was that all widgets were now based on a multi-handle (windowed) design. Each widget now has a window handle. Other GUI toolkits that follow a similar design are <a href="/facts/GTK/oLpVm9pp">GTK</a>, <a href="/facts/X_Toolkit_Intrinsics/bD9XueHe">Xt</a> and <a href="/facts/FLTK/a9R0RuQI">FLTK</a> to name a few. GUI toolkits that follow the opposite design are toolkits like the latest <a href="/facts/Qt_(framework)/gVhwlQnJ">Qt</a><a class="footnote-ref" id="fnref:1" href="#fn:1"><sup>1</sup></a> and MSEgui.
</p>
<h2 id="example-program">Example program</h2>
<p>The following program shows a single window with a "Quit" button in the bottom right. On the canvas (background) of the window it paints all the standard built-in images used with fpGUI.
</p>
program stdimglist;

{$mode objfpc}{$H+}

uses
  Classes, SysUtils,
  fpg_base, fpg_main, fpg_form, fpg_imgfmt_bmp, fpg_button;

type

TMainForm = class(TfpgForm)
  private
    btnClose: TfpgButton;
    procedure   btnCloseClick(Sender: TObject);
  protected
    procedure   HandlePaint; override;
  public
    constructor Create(aowner: TComponent); override;
    procedure   AfterCreate; override;
  end;

{ TMainForm }

procedure TMainForm.AfterCreate;
begin
  SetPosition(100,100,700,500);
  WindowTitle := 'fpGUI Standard Image Listing';
  // Place button in bottom right corner.
  btnClose := CreateButton(self, Width-90, Height-35, 75, 'Quit', @btnCloseClick);
  btnClose.ImageName := 'stdimg.quit';
  btnClose.Anchors := [anRight, anBottom];
end;

procedure TMainForm.btnCloseClick(Sender: TObject);
begin
  Close;
end;

procedure TMainForm.HandlePaint;
var
  n: integer;
  x: TfpgCoord;
  y: TfpgCoord;
  sl: TStringList;
  img: TfpgImage;
begin
  Canvas.BeginDraw; // begin double buffering
  inherited HandlePaint;

sl  := TStringList.Create;
  x   := 8;
  y   := 8;
  fpgImages.ListImages(sl);
  
  for n := 0 to sl.Count-1 do
  begin
    Canvas.DrawString(x, y, sl[n]+':');
    
    img := TfpgImage(sl.Objects[n]);
    if img <> nil then
      Canvas.DrawImage(x+130, y, img);

inc(y, img.Height+8);
    if y > Height-32 then // largest images are 32 in height
    begin
      inc(x, 200);
      y := 8;
    end;
  end;

Canvas.EndDraw;
  sl.Free;
end;

constructor TMainForm.Create(aowner: TComponent);
begin
  inherited Create(aowner);
(* PRIOR TO v1.4:
  // Place button in bottom right corner.
  btnClose := CreateButton(self, Width-90, Height-35, 75, 'Quit', @btnCloseClick);
  btnClose.ImageName := 'stdimg.quit';
  btnClose.Anchors := [anRight, anBottom];
*)
end;

procedure MainProc;
var
  frm : TMainForm;
begin
  fpgApplication.Initialize;
  frm := TMainForm.Create(nil);
  try
    frm.Show;
    fpgApplication.Run;
  finally
    frm.Free;
  end;
end;

begin
  MainProc;
end.

<p>Here is a screenshot of the above program when run under Linux.

</p>
<h2 id="licensing">Licensing</h2>
<p>fpGUI is statically linked into programs and is licensed using a modified version of LGPL specially designed to allow static linking to proprietary programs. The only code you need to make available are any changes you made to the fpGUI toolkit - nothing more.
</p>
<h2 id="software-written-with-fpgui">Software written with fpGUI</h2>
<ul><li><a href="http://www.mastermaths.co.za">Master Maths</a>Used in a computer-based training system. As well as a basic accounting and administration package for franchisees.</li>
<li>A Visual Form Designer which is now included as part of fpGUI. It allows the developer to create user interfaces at a much faster pace.</li>
<li><a href="https://web.archive.org/web/20090304183218/http://jmlesite.fr/Lazarus/prog_fpgui_en.php">Unimesur and various tools</a>Written by Jean-Marc, the Unimesur program allows to convert measurements of flows of liquids and gases, between mass and volume units. All results were verified for the exactness of the conversion factors.</li>
<li>fpGUI DocViewAn <a href="/facts/Information_Presentation_Facility/mxt2BlVE">INF help file</a> viewer that currently works on Windows,<a class="footnote-ref" id="fnref:2" href="#fn:2"><sup>2</sup></a> Linux and FreeBSD. INF is the default help format of fpGUI, and is also the help format used in <a href="/facts/OS%2f2/uVBl6ItP">OS/2</a> (and also <a href="/facts/EComStation/0FseHaUf">eComStation</a> and <a href="/facts/ArcaOS/KGRJJQTA">ArcaOS</a>).</li>
<li><a href="https://github.com/graemeg/fptest">Free Pascal Testing Framework</a>A cross-platform unit testing framework with a Console and GUI test runner.</li></ul>
<h2 id="see-also">See also</h2>
<ul>
<li>Free and open-source software portal</li></ul>
<ul><li><a href="/facts/Lazarus_(software)/6Il32HeV">Lazarus (software)</a></li>
<li><a href="/facts/Widget_toolkit/v8wM8wwy">Widget toolkit</a></li>
<li><a href="/facts/Qt_(toolkit)/gVhwlQnJ">Qt</a></li>
<li><a href="/facts/WxWidgets/TQvpa4Pl">wxWidgets</a></li>
<li><a href="/facts/GTK%252B/oLpVm9pp">GTK+</a></li>
<li><a href="/facts/FOX_toolkit/MnFjp0JB">FOX toolkit</a></li>
<li><a href="/facts/FLTK/a9R0RuQI">FLTK</a></li></ul>

<h2 id="external-links">External links</h2>
<ul><li><a href="http://fpgui.sourceforge.net/">official fpGUI Toolkit website</a></li>
<li><a href="http://sourceforge.net/projects/fpgui/">fpGUI's SourceForge.net project page</a></li>
<li><a href="http://www.freepascal.org">Free Pascal compiler</a> <a href="https://web.archive.org/web/19990125095436/http://www.freepascal.org/">Archived</a> 1999-01-25 at the <a href="/facts/Wayback_Machine/nmQ3a6JC">Wayback Machine</a></li>
<li><a href="http://lazarus.freepascal.org">Lazarus IDE</a></li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>"Trolltech Labs Blogs » Qt Invaded By Aliens — The End of All Flicker". Archived from the original on 2010-03-03. Retrieved 2008-03-08. <a href="https://web.archive.org/web/20100303024014/http://labs.trolltech.com/blogs/2007/08/09/qt-invaded-by-aliens-the-end-of-all-flicker#comment-15559" target="_blank">https://web.archive.org/web/20100303024014/http://labs.trolltech.com/blogs/2007/08/09/qt-invaded-by-aliens-the-end-of-all-flicker#comment-15559</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
<li id="fn:2"><p>Unlike old 16-bit IPF .inf/.hlp viewers DocView can be used on 64-bit Windows <a href="/wiki/Information_Presentation_Facility" target="_blank">/wiki/Information_Presentation_Facility</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li>
</ol>

fpGUI open-in-new

fpGUI