Theme library

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Revision as of 09:37, 31 May 2007 by Paul Ishenin (talk | contribs) (What is the current state of implementation?)

What is Theme manager?

Theme manager has been originally created by Mike Lischke (see http://www.soft-gems.net/) to enable Windows XP theme painting in Borland Delphi and Borland C++ Builder applications.

Why do we need Theme manager?

It gives the ability to have ownerdraw controls with the same look and feel as native controls.

What ownerdraw controls do we have?

  1. TCustomSpeedButton descendants (TSpeedButton)
  2. TCustomSplitter descendants (TSplitter)
  3. TCustomGrid descendants (TStringGrid, TDBGrid)
  4. ...

What is the current state of implementation?

Windows XP and Vista applications with manifest - fully implemented since theme manager originally created for Windows XP.

Element default gtk gtk2 carbon qt Used in components
teButton Partially Implemented Partially Implemented Partially Implemented Partially Implemented Not Implemented TSpeedButton
teHeader Partially Implemented Partially Implemented Partially Implemented Not Implemented Not Implemented TCustomGrid
teRebar Partially Implemented Partially Implemented Partially Implemented Partially Implemented Not Implemented TSplitter
teToolBar Partially Implemented Partially Implemented Partially Implemented Partially Implemented Not Implemented TSpeedButton

How to use ThemeServices class for painting?

It is rather simple. Let's do an empty form and paint a push button on it with normal state.

unit Unit1; 
{$mode objfpc}{$H+}

interface
uses
  Classes, SysUtils, LResources, Forms, Controls, Graphics;

type
  TForm1 = class(TForm)
  private
    { private declarations }
  public
    procedure Paint; override;
  end;

var
  Form1: TForm1; 

implementation
{$R manifest.res}

uses
  LCLType, Themes;
  
procedure TForm1.Paint;
var
  Details: TThemedElementDetails;
  PaintRect: TRect;
begin
  inherited Paint;
  PaintRect := Rect(10, 10, 80, 50);
  Details := ThemeServices.GetElementDetails(tbPushButtonNormal);
  ThemeServices.DrawElement(Canvas.Handle, Details, PaintRect, nil);
  PaintRect := ThemeServices.ContentRect(Canvas.Handle, Details, PaintRect);
  ThemeServices.DrawText(Canvas, Details, 'Test caption', PaintRect,
    DT_CENTER or DT_VCENTER or DT_SINGLELINE, 0);
end;

initialization
  {$I unit1.lrs}
end.

And the result will look so:

theme painting.png

--Paul Ishenin 08:11, 23 May 2007 (CEST)