mewin/nana
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

add methods for listbox visible range

Browse Source
This commit is contained in:
Jinhao 2018-12-02 06:44:11 +08:00
parent 07a971c6ef
commit 54cfd3075d
2 changed files with 69 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
include/nana/gui/widgets/listbox.hpp
View File

@ -1555,6 +1555,27 @@ the nana::detail::basic_window member pointer scheme
* @return the reference of *this.
*/
listbox& category_icon(const paint::image& img_expanded, const paint::image&& img_collapsed);
/// Returns first visible element
/**
* It may return an item or a category item.
* @return the index of first visible element.
*/
index_pair first_visible() const;
/// Returns last visible element
/**
* It may return an item or a category item.
* @return the index of last visible element.
*/
index_pair last_visible() const;
/// Returns all visible items
/**
* It returns all visible items that are displayed in listbox window.
* @return index_pairs containing all visible items.
*/
index_pairs visibles() const;
private:
drawerbase::listbox::essence & _m_ess() const;
nana::any* _m_anyobj(size_type cat, size_type index, bool allocate_if_empty) const override;

48
source/gui/widgets/listbox.cpp
View File

@ -5989,6 +5989,54 @@ namespace nana
return *this;
}
auto listbox::first_visible() const ->index_pair
{
return _m_ess().first_display();
}
auto listbox::last_visible() const -> index_pair
{
return _m_ess().lister.advance(_m_ess().first_display(), _m_ess().count_of_exposed(true));
}
auto listbox::visibles() const -> index_pairs
{
index_pairs indexes;
auto idx = _m_ess().first_display();
auto n = _m_ess().count_of_exposed(true);
while (n > 0)
{
if (idx.empty())
break;
if (idx.is_category())
{
indexes.push_back(idx);
--n;
}
else
{
auto const count = (std::min)(_m_ess().lister.size_item(idx.cat) - idx.item, n);
for (std::size_t i = 0; i < count; ++i)
{
indexes.push_back(idx);
++idx.item;
}
if (count)
{
n -= count;
--idx.item;
}
}
idx = _m_ess().lister.advance(idx, 1);
}
return indexes;
}
drawerbase::listbox::essence & listbox::_m_ess() const
{
return get_drawer_trigger().ess();