// Copyright (c) 2017-2021, Mudita Sp. z.o.o. All rights reserved.
// For licensing, see https://github.com/mudita/MuditaOS/LICENSE.md
#pragma once
#include <list>
#include "Rect.hpp"
#include "BoxLayout.hpp"
#include "Span.hpp"
#include "ListItemProvider.hpp"
#include "Style.hpp"
namespace gui
{
namespace listview
{
inline constexpr auto nPos = std::numeric_limits<unsigned int>::max();
/// Possible List boundaries handling types
enum class Boundaries
{
Fixed, ///< Fixed - list will stop scrolling on first or last elements on appropriate top or bottom
///< directions.
Continuous ///< Continuous - list will continue to beginning or end on first or last elements on
///< appropriate top or bottom directions.
};
/// Possible List scrolling directions
enum class Direction
{
Top,
Bottom
};
/// Possible List rebuild types
enum class RebuildType
{
Full, ///< Full rebuild - resets lists to all initial conditions and request data from beginning.
InPlace, ///< InPlace rebuild - stores currently focused part of list and rebuild from that part.
OnPageElement, ///< OnPageElement rebuild - same page but focus changed on provided element index.
OnOffset ///< OnOffset rebuild - resets lists to all initial conditions and request data from provided
///< offset.
};
/// Possible List ScrollBar types
enum class ScrollBarType
{
None, ///< None - list without scroll bar (but with scrolling).
Proportional, ///< Proportional - scroll bar size calculated based on elements count in model and currently
///< displayed number of elements. Use with large unequal heights lists elements.
Fixed, ///< Fixed - scroll bar size calculated based on fixed equal elements sizes in list.
///< Use when all elements have equal heights.
PreRendered ///< PreRendered - scroll bar size calculated based on pre rendered pages on whole list. Use
///< when elements are not equal heights but there are few of them as its renders whole
///< context and can be time consuming.
};
enum class Orientation
{
TopBottom,
BottomTop
};
} // namespace listview
class ListItemProvider;
using rebuildRequest = std::pair<listview::RebuildType, unsigned int>;
struct ListViewScrollUpdateData
{
const unsigned int startIndex;
const unsigned int listPageSize;
const unsigned int elementsCount;
const unsigned int elementMinimalHeight;
const listview::Direction direction;
const listview::Boundaries boundaries;
const int topMargin;
};
class ListViewScroll : public Rect
{
private:
unsigned int storedStartIndex = 0;
unsigned int currentPage = listview::nPos;
unsigned int pagesCount = 0;
void updateProportional(const ListViewScrollUpdateData &data);
void updateFixed(const ListViewScrollUpdateData &data);
void updatePreRendered(const ListViewScrollUpdateData &data);
public:
listview::ScrollBarType type = listview::ScrollBarType::None;
ListViewScroll(
Item *parent, unsigned int x, unsigned int y, unsigned int w, unsigned int h, listview::ScrollBarType type);
bool shouldShowScroll(unsigned int listPageSize, unsigned int elementsCount);
void updateStartConditions(const unsigned int storedStartIndex,
const unsigned int currentPage,
const unsigned int pagesCount);
void update(const ListViewScrollUpdateData &data);
};
class ListView : public Rect
{
protected:
unsigned int startIndex = 0;
unsigned int storedFocusIndex = listview::nPos;
unsigned int elementsCount = 0;
std::shared_ptr<ListItemProvider> provider = nullptr;
VBox *body = nullptr;
ListViewScroll *scroll = nullptr;
std::list<rebuildRequest> rebuildRequests;
rebuildRequest lastRebuildRequest = {listview::RebuildType::Full, 0};
unsigned int currentPageSize = 0;
bool pageLoaded = true;
bool focusOnLastItem = false;
int scrollTopMargin = style::margins::big;
listview::Boundaries boundaries = listview::Boundaries::Fixed;
listview::Direction direction = listview::Direction::Bottom;
listview::Orientation orientation = listview::Orientation::TopBottom;
virtual void addItemsOnPage();
bool requestCompleteData = false;
bool requestFullListRender = false;
bool renderFullList();
void checkFullRenderRequirement();
void prepareFullRebuild();
void prepareOnOffsetRebuild(unsigned int dataOffset);
void prepareInPlaceRebuild();
void prepareOnPageElementRebuild(unsigned int dataOffset);
void setFocus();
void refresh();
void resizeWithScroll();
void recalculateStartIndex();
void fillFirstPage();
void setStartIndex();
void recalculateOnBoxRequestedResize();
void setFocusOnElement(unsigned int elementNumber);
[[nodiscard]] unsigned int getFocusItemIndex();
/// Default empty list to inform that there is no elements - callback should be override in applications
void onElementsCountChanged();
unsigned int calculateMaxItemsOnPage();
unsigned int calculateLimit(listview::Direction value = listview::Direction::Bottom);
[[nodiscard]] Order getOrderFromDirection() const noexcept;
[[nodiscard]] Order getOppositeOrderFromDirection() const noexcept;
virtual bool requestNextPage();
virtual bool requestPreviousPage();
void setup(listview::RebuildType rebuildType, unsigned int dataOffset = 0);
public:
ListView();
ListView(Item *parent,
unsigned int x,
unsigned int y,
unsigned int w,
unsigned int h,
std::shared_ptr<ListItemProvider> prov,
listview::ScrollBarType scrollType = listview::ScrollBarType::Proportional);
~ListView();
void setElementsCount(unsigned int count);
void setProvider(std::shared_ptr<ListItemProvider> provider);
void rebuildList(listview::RebuildType rebuildType = listview::RebuildType::Full,
unsigned int dataOffset = 0,
bool forceRebuild = false);
/// In case of elements count change there can be a need to resend request in case of having one async query for
/// count and records.
void reSendLastRebuildRequest();
/// Callback to be called on rebuild preparation - in example to on demand clear provider data.
std::function<void()> prepareRebuildCallback;
void reset();
void clear();
void onClose();
std::shared_ptr<ListItemProvider> getProvider();
void setOrientation(listview::Orientation value);
void setBoundaries(listview::Boundaries value);
void setScrollTopMargin(int value);
void setAlignment(const Alignment &value) override;
void onProviderDataUpdate();
[[nodiscard]] bool isEmpty() const noexcept;
std::function<void()> emptyListCallback;
std::function<void()> notEmptyListCallback;
// virtual methods from Item
bool onInput(const InputEvent &inputEvent) override;
bool onDimensionChanged(const BoundingBox &oldDim, const BoundingBox &newDim) override;
auto handleRequestResize(const Item *, Length request_w, Length request_h) -> Size override;
};
} /* namespace gui */