Transparente Listbox

[shmia]

Im folgenden eine transparente Listbox (ungetestet):

Delphi-Quellcode:

type
  TTransparentListBox = class(TListBox)
  private
    procedure WMEraseBkgnd(var Message: TWmEraseBkgnd); message WM_ERASEBKGND;
  protected
    procedure CreateParams(var Params: TCreateParams); override;
  end;

implementation

procedure TTransparentListBox.CreateParams(var Params: TCreateParams);
begin
  inherited CreateParams(Params);
  Params.ExStyle:= Params.ExStyle or WS_EX_TRANSPARENT;
end;

procedure TTransparentListBox.WMEraseBkgnd(var Message: TWmEraseBkgnd);
begin
  // in this case, we want to intercept the windows message. if we would want to
  // pass the message to the ancestor classes, we could use the keyword
  // "inherited" without the procedure name. example:
  //   inherited;
  Message.Result := 1;
end;

PS: Verschwende deine Zeit nicht mit nutzlosen optischen Gimmicks.