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Article #16079: Draw on frame

 Question and Answer Database

FAQ1079D.txt   Draw on frame
Category   :VCL
Platform    :All
Product    :All 32 bit  

Question:
Is it possible to draw on the frame of a form?

Answer:
Create a message handler for the Windows Message WM_NCPAINT
message. The following example paints a 1 pixel red border around the
frame of the form.

Example:

type
  TForm1 = class(TForm)
  private
    { Private declarations }
    procedure WMNCPaint(var Msg : TWMNCPaint); message WM_NCPAINT;
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.WMNCPaint(var Msg: TWMNCPaint);
var
  dc : hDc;
  Pen : hPen;
  OldPen : hPen;
  OldBrush : hBrush;
begin
  inherited;
  dc := GetWindowDC(Handle);
  msg.Result := 1;
  Pen := CreatePen(PS_SOLID, 1, RGB(255, 0, 0));
  OldPen := SelectObject(dc, Pen);
  OldBrush := SelectObject(dc, GetStockObject(NULL_BRUSH));
  Rectangle(dc, 0,0, Form1.Width, Form1.Height);
  SelectObject(dc, OldBrush);
  SelectObject(dc, OldPen);
  DeleteObject(Pen);
  ReleaseDC(Handle, Canvas.Handle);
end;



7/16/98 4:31:28 PM
 

Last Modified: 01-SEP-99