Function ShowDropDownList

src/dropdown.cpp:418–445

* Show a drop down list. * @param w Parent window for the list. * @param list Prepopulated DropDownList. * @param selected The initially selected list item. * @param button The widget within the parent window that is used to determine * the list's location. * @param width Override the minimum width determined by the selected widget and list contents. * @param

 * @param options Drop Down options for this menu.
 */
void ShowDropDownList(Window *w, DropDownList &&list, int selected, WidgetID button, uint width, DropDownOptions options)
{
	/* Handle the beep of the player's click. */
	SndClickBeep();

	/* Our parent's button widget is used to determine where to place the drop
	 * down list window. */
	NWidgetCore *nwi = w->GetWidget<NWidgetCore>(button);
	Rect wi_rect      = nwi->GetCurrentRect();
	Colours wi_colour = nwi->colour;

	if ((nwi->type & WWT_MASK) == NWID_BUTTON_DROPDOWN) {
		nwi->disp_flags.Set(NWidgetDisplayFlag::DropdownActive);
	} else {
		nwi->SetLowered(true);
	}
	nwi->SetDirty(w);

	if (width != 0) {
		if (_current_text_dir == TD_RTL) {
			wi_rect.left = wi_rect.right + 1 - ScaleGUITrad(width);
		} else {
			wi_rect.right = wi_rect.left + ScaleGUITrad(width) - 1;
		}
	}

	ShowDropDownListAt(w, std::move(list), selected, button, wi_rect, wi_colour, options);
}

/**
 * Show a dropdown menu window near a widget of the parent window.