Probleme mit TDBLookupListBox und Mausrad (scrollen)

[marabu]

Hallo,

Zitat von Beg:

kann man in einer TDBLookupListBox mit dem Mausrad scrollen?

aber sicher kann man das:

Delphi-Quellcode:

type
  TDemoForm = class(TForm)
    DBLookupListBox: TDBLookupListBox;
    procedure FormCreate(Sender: TObject);
  private
    procedure DBLookupListBoxMouseWheelDown(Sender: TObject;
      Shift: TShiftState; MousePos: TPoint; var Handled: Boolean);
    procedure DBLookupListBoxMouseWheelUp(Sender: TObject;
      Shift: TShiftState; MousePos: TPoint; var Handled: Boolean);
  end;
implementation

type
  THackedDBLookupListBox = class(TDBLookupListBox);

procedure TDemoForm.FormCreate(Sender: TObject);
begin
  with THackedDBLookupListBox(DBLookupListBox) do
  begin
    OnMouseWheelDown := DBLookupListBoxMouseWheelDown;
    OnMouseWheelUp := DBLookupListBoxMouseWheelUp;
  end;
end;

procedure TDemoForm.DBLookupListBoxMouseWheelDown(Sender: TObject;
  Shift: TShiftState; MousePos: TPoint; var Handled: Boolean);
begin
  with Sender as TDBLookupListBox do
  begin
    DataSource.Edit;
    ListSource.DataSet.MoveBy(1);
    DataSource.DataSet.FieldValues[DataField] := ListSource.DataSet.FieldValues[KeyField];
  end;
  Handled := true;
end;

procedure TDemoForm.DBLookupListBoxMouseWheelUp(Sender: TObject;
  Shift: TShiftState; MousePos: TPoint; var Handled: Boolean);
begin
  with Sender as TDBLookupListBox do
  begin
    DataSource.Edit;
    ListSource.DataSet.MoveBy(-1);
    DataSource.DataSet.FieldValues[DataField] := ListSource.DataSet.FieldValues[KeyField];
  end;
  Handled := true;
end;

Grüße vom marabu