This should explain it. Start a new project with a blank Form.
uses Windows;
procedure RTLCtrl(ACtrl: TObject);
begin
if ACtrl is TWinControl then
with TWinControl(ACtrl) do begin
SetWindowLong(Handle, GWL_EXSTYLE, GetWindowLong(Handle, GWL_EXSTYLE)
or WS_EX_LAYOUTRTL);
end;
end;
procedure TForm1.FormCreate(Sender: TObject);
var
ACombo: TComboBox;
ALabel: TLabel;
begin
ACombo:= TComboBox.Create(Self);
ACombo.Parent:= Self;
ALabel:= TLabel.Create(Self);
ALabel.Parent:= Self;
ALabel.Anchors:= [];
RtlCtrl(Self);
end;