Simpelt spørgsmål om komponent

Kunne du eventuelt uddybe dine fejlbeskeder? Husk hvis den Class som du laver
proceduren under har en Resize procedure skal du enten Rename din egen eller override den.

I får lige hele kilde-koden.
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unit Effect;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, JPEG,
  Dialogs, StdCtrls, Forms, extctrls, WinIoCtl;

type
  TEffect = class(TComponent)
  private
    { Private declarations }

  protected
    { Protected declarations }

  public
    { Public declarations }
    Constructor Create(AOwner: TComponent); override;
    Destructor Destroy; override;

  published
    { Published declarations }
    Procedure GrayScale(Value: TImage); overload;
    Procedure Resize(Value: TImage; Width: Integer; Height: Integer);
  end;

procedure Register;

implementation

procedure Register;
begin
  RegisterComponents('PDJ', [TEffect]);
end;

constructor TEffect.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
end;

destructor TEffect.Destroy;
begin
  inherited Destroy;
end;

procedure TEffect.GrayScale(Value: TImage);
var
Gray, X, Y : Integer;
PByte : PByteArray;
begin
with Value.Picture.Bitmap do
begin
  for Y := 0 to Height -1 do
  begin
    PByte := ScanLine[Y];
    for X := 0 to Width -1 do
    begin
      Gray := Round(PByte[X * 3] * 0.3 + PByte[X * 3 + 1] * 0.59 + PByte[X * 3 + 2] * 0.11);
      PByte[X * 3] := Gray;
      PByte[X * 3 + 1] := Gray;
      PByte[X * 3 + 2] := Gray;
    end;
  end;
end;
  Value.Refresh;
end;

Procedure Resize(Value: TImage; Width: Integer; Height: Integer);
var
    BitmapOriginal:  TBitmap;
    BItmapNew    :  TBitmap;
begin
  BitmapOriginal := TBitmap.Create;
  try
    BitmapOriginal.LoadFromFile(Value.Picture.Bitmap.GetNamePath);
    BitmapNew := TBitmap.Create;
    try
      BitmapNew.Width  := Width;
      BitmapNew.Height := Height;
      BitmapNew.PixelFormat := pf24bit;
      BitmapNew.Canvas.StretchDraw(
          BitmapNew.Canvas.ClipRect,
          BitmapOriginal);
      Value.Picture.Graphic := BitmapNew
    finally
      BitmapNew.Free
    end
  finally
    BitmapOriginal.Free
  end
end;

end.
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Overload og override har jeg forsøgt mig med, uden held.
Når jeg vil compile den for jeg følgende besked "Unsatisfied forward or external declaration".

Det er fordi du mangler class navnet TEffect i din procedure erklæring. som her: TEffect.Resize du har kun Resize stående.

Hvis jeg mangler class navnet, hvorfor virker det så med grayscale?

Fordi der har du skrevet det rigtigt.Viser lige:
Denne er rigtig
procedure TEffect.GrayScale(Value: TImage);

Denne er forkert
Procedure Resize(Value: TImage; Width: Integer; Height: Integer);

Denne er rigtig
Procedure TEffect.Resize(Value: TImage; Width: Integer; Height: Integer);

tg

Hvad så virker det?