/**
* Find the dropdown item under the cursor.
* @param value [out] Selected item, if function returns \c true.
* @return Cursor points to a dropdown item.
*/
bool GetDropDownItem(int &value)
{
if (GetWidgetFromPos(this, _cursor.pos.x - this->left, _cursor.pos.y - this->top) < 0) return false;
NWidgetBase *nwi = this->GetWidget<NWidgetBase>(WID_DM_ITEMS);
int y = _cursor.pos.y - this->top - nwi->pos_y - 2;
int width = nwi->current_x - 4;
int pos = this->vscroll->GetPosition();
const DropDownList *list = this->list;
for (const DropDownListItem * const *it = list->Begin(); it != list->End(); ++it) {
/* Skip items that are scrolled up */
if (--pos >= 0) continue;
const DropDownListItem *item = *it;
int item_height = item->Height(width);
if (y < item_height) {
if (item->masked || !item->Selectable()) return false;
value = item->result;
return true;
}
y -= item_height;
}
return false;
}
/**
* Create a dropdown menu.
* @param parent Parent window.
* @param list Dropdown item list.
* @param selected Index of the selected item in the list.
* @param button Widget of the parent window doing the dropdown.
* @param instant_close Close the window when the mouse button is raised.
* @param position Topleft position of the dropdown menu window.
* @param size Size of the dropdown menu window.
* @param wi_colour Colour of the parent widget.
* @param scroll Dropdown menu has a scrollbar.
* @param widget Widgets of the dropdown menu window.
*/
DropdownWindow(Window *parent, const DropDownList *list, int selected, int button, bool instant_close, const Point &position, const Dimension &size, Colours wi_colour, bool scroll)
: Window(&_dropdown_desc)
{
assert(list->Length() > 0);
this->position = position;
this->CreateNestedTree();
this->vscroll = this->GetScrollbar(WID_DM_SCROLL);
uint items_width = size.width - (scroll ? NWidgetScrollbar::GetVerticalDimension().width : 0);
NWidgetCore *nwi = this->GetWidget<NWidgetCore>(WID_DM_ITEMS);
nwi->SetMinimalSize(items_width, size.height + 4);
nwi->colour = wi_colour;
nwi = this->GetWidget<NWidgetCore>(WID_DM_SCROLL);
nwi->colour = wi_colour;
this->GetWidget<NWidgetStacked>(WID_DM_SHOW_SCROLL)->SetDisplayedPlane(scroll ? 0 : SZSP_NONE);
this->FinishInitNested(0);
CLRBITS(this->flags, WF_WHITE_BORDER);
/* Total length of list */
int list_height = 0;
for (const DropDownListItem * const *it = list->Begin(); it != list->End(); ++it) {
const DropDownListItem *item = *it;
list_height += item->Height(items_width);
}
/* Capacity is the average number of items visible */
this->vscroll->SetCapacity(size.height * (uint16)list->Length() / list_height);
this->vscroll->SetCount((uint16)list->Length());
this->parent_wnd_class = parent->window_class;
this->parent_wnd_num = parent->window_number;
this->parent_button = button;
this->list = list;
this->selected_index = selected;
this->click_delay = 0;
this->drag_mode = instant_close;
this->instant_close = instant_close;
this->left_button_state = _left_button_down;
}