From Lazarus-ccr

[edit] 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.

[edit] Why do we need Theme manager?

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

[edit] What ownerdraw controls do we have?

1. TCustomSpeedButton descendants (TSpeedButton)
2. TCustomSplitter descendants (TSplitter)
3. TCustomGrid descendants (TStringGrid, TDBGrid)
4. TCustomUpDown descendants (TUpDown)
5. ...

[edit] What is the current state of implementation?

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

[edit] 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:

--Paul Ishenin 20:31, 9 June 2007 (CEST)