Operacje graficzne na pasku tytułowym programu

Aby mieć możliwość rysowania po powierzchni paska tytułowego, musimy utworzyć nowy obiekt TCanvas, a następnie przypisać mu uchwyt naszego formularza.

type 

  TForm1 = class(TForm) 

  private 

    procedure WMNCPaint(var Msg: TWMNCPaint); message WM_NCPAINT; 

  public 

  end; 


var 

  Form1: TForm1; 


implementation 


{$r *.dfm} 


procedure TForm1.WMNCPaint(var Msg: TWMNCPaint); 

var 

  ACanvas: TCanvas; 

begin 

  inherited; 

  ACanvas := TCanvas.Create; 

  try 

    ACanvas.Handle := GetWindowDC(Form1.Handle); 

    with ACanvas do  

    begin 

      Brush.Color := clActiveCaption; 

      Font.Name := 'Tahoma'; 

      Font.Size := 8; 

      Font.Color := clred; 

      Font.Style := [fsItalic, fsBold]; 

      TextOut(GetSystemMetrics(SM_CYMENU) + GetSystemMetrics(SM_CXBORDER), 

        Round((GetSystemMetrics(SM_CYCAPTION) - Abs(Font.Height)) / 2) + 1, ' Taki tam tekst'); 

    end; 

  finally 

    ReleaseDC(Form1.Handle, ACanvas.Handle); 

    ACanvas.Free; 

  end; 

end;

type

TForm1 = class(TForm)

private

procedure WMNCPaint(var Msg: TWMNCPaint); message WM_NCPAINT;

public

end;

var

Form1: TForm1;

implementation

{$r *.dfm}

procedure TForm1.WMNCPaint(var Msg: TWMNCPaint);

var

ACanvas: TCanvas;

begin

inherited;

ACanvas := TCanvas.Create;

try

ACanvas.Handle := GetWindowDC(Form1.Handle);

with ACanvas do

begin

Brush.Color := clActiveCaption;

Font.Name := 'Tahoma';

Font.Size := 8;

Font.Color := clred;

Font.Style := [fsItalic, fsBold];

TextOut(GetSystemMetrics(SM_CYMENU) + GetSystemMetrics(SM_CXBORDER),

Round((GetSystemMetrics(SM_CYCAPTION) - Abs(Font.Height)) / 2) + 1, ' Taki tam tekst');

end;

finally

ReleaseDC(Form1.Handle, ACanvas.Handle);

ACanvas.Free;

end;

Autor: Nakiel