Drawing text on desktop

Using this simple trick, you can write any text right on Windows desktop. You can choose text color, transparency, position…

This trick has one little problem. As you can see, if you move some window or any object (icon) over the text, it will be deleted. So you
must take of “redrawing” the text.

unit Unit1;
 
interface
 
uses
 Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
 Dialogs, StdCtrls;
 
type
 TForm1 = class(TForm)
 Button1: TButton;
 procedure Button1Click(Sender: TObject);
 private
 { Private declarations }
 public
 { Public declarations }
 end;
 
var
 Form1: TForm1;
 
implementation
 
{$R *.dfm}
 
procedure TForm1.Button1Click(Sender: TObject);
var dc: hdc;
 ocolor: COLORREF;
 oBKM : integer;
 OurText: PAnsiChar;
begin
 OurText := 'Hello, World!';
 dc := GetWindowDC(GetDesktopWindow);
 try
 ocolor := SetTextColor(DC, RGB(0, 255, 0));
 oBKM := SetBkMode(DC, TRANSPARENT);
 TextOut(DC, 500, 300, OurText, Length(OurText));
 SetBkMode(DC, oBKM);
 SetTextColor(DC, ocolor);
 finally
 ReleaseDC(GetDesktopWindow, DC);
 end;
end;
 
end.

unit Unit1;

interface

uses

Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

Dialogs, StdCtrls;

type

TForm1 = class(TForm)

Button1: TButton;

procedure Button1Click(Sender: TObject);

private

{ Private declarations }

public

{ Public declarations }

end;

var

Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);

var dc: hdc;

ocolor: COLORREF;

oBKM : integer;

OurText: PAnsiChar;

begin

OurText := 'Hello, World!';

dc := GetWindowDC(GetDesktopWindow);

try

ocolor := SetTextColor(DC, RGB(0, 255, 0));

oBKM := SetBkMode(DC, TRANSPARENT);

TextOut(DC, 500, 300, OurText, Length(OurText));

SetBkMode(DC, oBKM);

SetTextColor(DC, ocolor);

finally

ReleaseDC(GetDesktopWindow, DC);

end;

end.

Make a question and you'll have an answer…

Make a question and you'll have an answer…

Drawing text on desktop