procedure TCustomListBox.CreateParams(var Params: TCreateParams);
type
PSelects = ^TSelects;
TSelects = array[Boolean] of DWORD;
const
Styles: array[TListBoxStyle] of DWORD =
(0, LBS_OWNERDRAWFIXED, LBS_OWNERDRAWVARIABLE);
Sorteds: array[Boolean] of DWORD = (0, LBS_SORT);
MultiSelects: array[Boolean] of DWORD = (0, LBS_MULTIPLESEL);
ExtendSelects: array[Boolean] of DWORD = (0, LBS_EXTENDEDSEL);
IntegralHeights: array[Boolean] of DWORD = (LBS_NOINTEGRALHEIGHT, 0);
MultiColumns: array[Boolean] of DWORD = (0, LBS_MULTICOLUMN);
TabStops: array[Boolean] of DWORD = (0, LBS_USETABSTOPS);
CSHREDRAW: array[Boolean] of DWORD = (CS_HREDRAW, 0);
var
Selects: PSelects;
begin
inherited CreateParams(Params);
CreateSubClass(Params, 'LISTBOX');
with Params do
begin
Selects := @MultiSelects;
if FExtendedSelect then Selects := @ExtendSelects;
Style := Style or (WS_HSCROLL or WS_VSCROLL or LBS_HASSTRINGS or
LBS_NOTIFY) or Styles[FStyle] or Sorteds[FSorted] or
Selects^[FMultiSelect] or IntegralHeights[FIntegralHeight] or
MultiColumns[FColumns <> 0] or BorderStyles[FBorderStyle] or
TabStops[FTabWidth <> 0];
if NewStyleControls and Ctl3D and (FBorderStyle = bsSingle) then
begin
Style := Style and not WS_BORDER;
ExStyle := ExStyle or WS_EX_CLIENTEDGE;
end;
WindowClass.style := WindowClass.style and not (CSHREDRAW[UseRightToLeftAlignment] or CS_VREDRAW);
end;
end;