OOP-TRealEdit von TEdit abgeleitet und Fähigkeiten erweitert

[Hansa]

hier ist noch der momentane Code (das Label will einfach noch nicht) :

Code:

Unit RealEdit;

interface

uses
  Windows, Messages, SysUtils,
  Variants, Classes, Graphics,
  Controls, Forms, Dialogs, StdCtrls,ExtCtrls;

procedure Register;

type
  TRealEdit = class(TCustomEdit)
  private
    fAlignment:TAlignment;
    fOnlyReals:boolean;
    fLabel:TLabel;
    procedure SetAlignment(Value:TAlignment);
    procedure SetOnlyReals(Value:boolean);
  protected
    procedure SetLabel(Value:TLabel);
    procedure CreateParams(var Params:TCreateParams); override;
    procedure KeyPress(var Key:Char); override;
  public
    constructor Create(AOwner: TComponent); override;
    destructor destroy; override;
  published
    property Alignment: TAlignment read fAlignment write SetAlignment;
    property OnlyReals: Boolean read fOnlyReals write SetOnlyReals;
    property RealLabel: TLabel read fLabel write SetLabel;
  end;

implementation

procedure TRealEdit.SetLabel (Value : TLabel);
  begin
   fLabel := value;
   flabel.SetSubComponent(true);
  end;

constructor TRealEdit.Create(AOwner: TComponent);
begin
  inherited;
  FAlignment := taRightJustify;
  OnlyReals := true;
  FLabel := TLabel.Create(AOwner);
//  FLabel.Parent := AOwner;
  FLabel.Name := 'RealLabel';
  FLabel.SetSubComponent(true);
  FLabel.Caption := 'CAPTION';
end;

destructor TRealEdit.Destroy;
  begin
    FLabel.Destroy;
    inherited;
  end;

procedure TRealEdit.CreateParams(var Params: TCreateParams);
const Alignments: array[TAlignment] of byte=(ES_Left, ES_Right, ES_Center);
begin
  inherited CreateParams(Params);
  Params.Style := Params.Style or Alignments[fAlignment];
  fAlignMent := taRightJustify;
end;

procedure TRealEdit.KeyPress(var Key:Char);
var ZulZeichen : SET OF char;
begin
  inherited KeyPress(Key);
  if OnlyReals then begin
    ZulZeichen := ['0'..'9',#8];
    if pos (DecimalSeparator,text) = 0 THEN  // kein . im RealEdit.text . zulassen
      ZulZeichen := ZulZeichen + [DecimalSeparator]
    else
      ZulZeichen := ZulZeichen - [DecimalSeparator]; // zweiten .  verhindern
    if not (Key in ZulZeichen) then
      Key := #0;
  end;
end;

procedure TRealEdit.SetAlignment (value:TAlignment);
begin
  fAlignment:=value;
  RecreateWnd;
end;

procedure TRealEdit.SetOnlyReals (value:boolean);
begin
  fOnlyReals:=value;
  RecreateWnd;
end;

procedure Register;
begin
  RegisterComponents('Eigene', [TRealEdit]);
end;

end.