Pt ModalListPicker::DetermineListHeight(const Pt& _drop_down_size) {
auto drop_down_size = _drop_down_size;
// Determine the expected height
auto border_thick = 2 * GG::Y(ListBox::BORDER_THICK);
auto num_rows = std::min<int>(m_num_shown_rows, LB()->NumRows());
auto row_height = (*LB()->FirstRowShown())->Height();
auto expected_height = num_rows * row_height + border_thick;
// Shrink the height if too near app edge.
auto dist_to_app_edge = GUI::GetGUI()->AppHeight() - m_relative_to_wnd->Bottom();
if (expected_height > dist_to_app_edge && row_height > 0) {
auto reduced_num_rows = std::max(GG::Y(1), (dist_to_app_edge - border_thick) / row_height);
expected_height = reduced_num_rows * row_height + border_thick;
}
drop_down_size.y = expected_height;
LB()->Resize(drop_down_size);
if (!LB()->Selections().empty())
LB()->BringRowIntoView(*(LB()->Selections().begin()));
GUI::GetGUI()->PreRenderWindow(LB());
return drop_down_size;
}
void ModalListPicker::CompleteConstruction()
{
m_lb_wnd->SelRowsChangedSignal.connect(
boost::bind(&ModalListPicker::LBSelChangedSlot, this, _1));
m_lb_wnd->LeftClickedRowSignal.connect(
boost::bind(&ModalListPicker::LBLeftClickSlot, this, _1, _2, _3));
GUI::GetGUI()->WindowResizedSignal.connect(
boost::bind(&ModalListPicker::WindowResizedSlot, this, _1, _2));
AttachChild(m_lb_wnd);
m_lb_wnd->InstallEventFilter(shared_from_this());
if (INSTRUMENT_ALL_SIGNALS)
SelChangedSignal.connect(ModalListPickerSelChangedEcho(*this));
if (m_relative_to_wnd)
m_lb_wnd->MoveTo(Pt(m_relative_to_wnd->Left(), m_relative_to_wnd->Bottom()));
m_lb_wnd->Hide();
}
void ModalListPicker::CorrectListSize() {
// reset size of displayed drop list based on number of shown rows set.
// assumes that all rows have the same height.
// adds some magic padding for now to prevent the scroll bars showing up.
if (!m_relative_to_wnd)
return;
if (LB()->Visible())
return;
LB()->MoveTo(Pt(m_relative_to_wnd->Left(), m_relative_to_wnd->Bottom()));
Pt drop_down_size(m_relative_to_wnd->DroppedRowWidth(), m_relative_to_wnd->ClientHeight());
if (LB()->Empty()) {
LB()->Resize(drop_down_size);
} else {
LB()->Show();
// The purpose of this code is to produce a drop down list that
// will be exactly m_num_shown_rows high and make sure that the
// selected row is prerendered in the same way when the drop down
// list is open or closed.
// The list needs to be resized twice. The first resize with an
// estimated row height will add any list box chrome, like scroll
// bars to the list and may change the height of the row. The
// second resize uses the corrected row height to finalize the drop
// down list size.
// Note: Placing a tighter constraint on valid DropDownList rows
// of always returning the same fixed height regardless of status
// (width, prerender etc.) would mean this code could be reduced to
// check height and resize list just once.
drop_down_size = DetermineListHeight(drop_down_size);
DetermineListHeight(drop_down_size);
LB()->Hide();
}
}