direktive "message"

[sniper_w]

Delphi-Quellcode:

type
  TmyRichEdit = class(TRichEdit)
   procedure WMSetFocus(var msg: TWMSetFocus); message WM_SETFOCUS;
  end;

  TForm1 = class(TForm)
    RichEdit1: TRichEdit;
    Edit1: TEdit;
    procedure FormCreate(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    REdit : TmyRichEdit;
  end;

var
  Form1: TForm1;
  done : boolean = false;

implementation

{$R *.dfm}

procedure TmyRichEdit.WMSetFocus(var msg: TWMSetFocus);
begin
 inherited;

 if not done then
        begin
         Application.MessageBox('Und jetzt ist die schon ausgeführt.','FOCUS MESSAGE');
         done := true;// damit nur einmal diese Meldung kommt
        end;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
 REdit := TmyRichEdit.Create(self);

 with REdit do
 begin
  Parent := Self;
  Align := alLeft;
  Visible := true;
 end;
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
 REdit.Free;
end;

Es sollte genug selbserklärend sein.