Scrollbar Class Reference

Scrollbar data structure. More...

#include <widget_type.h>

Inheritance diagram for Scrollbar:

Public Types
enum	ScrollbarStepping { SS_RAW, SS_SMALL, SS_BIG }
	Stepping sizes when scrolling. More...
using	size_type = int32_t

Public Member Functions
	Scrollbar (bool is_vertical)
size_type	GetCount () const
	Gets the number of elements in the list. More...
size_type	GetCapacity () const
	Gets the number of visible elements of the scrollbar. More...
size_type	GetPosition () const
	Gets the position of the first visible element in the list. More...
bool	IsVisible (size_type item) const
	Checks whether given current item is visible in the list. More...
bool	IsVertical () const
	Is the scrollbar vertical or not? More...
void	SetStepSize (size_t stepsize)
	Set the distance to scroll when using the buttons or the wheel. More...
void	SetCount (size_t num)
	Sets the number of elements in the list. More...
void	SetCapacity (size_t capacity)
	Set the capacity of visible elements. More...
void	SetCapacityFromWidget (Window *w, WidgetID widget, int padding=0)
	Set capacity of visible elements from the size and resize properties of a widget. More...
bool	SetPosition (size_type position)
	Sets the position of the first visible element. More...
bool	UpdatePosition (int difference, ScrollbarStepping unit=SS_SMALL)
	Updates the position of the first visible element by the given amount. More...
void	ScrollTowards (size_type position)
	Scroll towards the given position; if the item is visible nothing happens, otherwise it will be shown either at the bottom or top of the window depending on where in the list it was. More...
size_type	GetScrolledRowFromWidget (int clickpos, const Window *const w, WidgetID widget, int padding=0, int line_height=-1) const
	Compute the row of a scrolled widget that a user clicked in. More...
template<typename Tcontainer >
auto	GetVisibleRangeIterators (Tcontainer &container) const
	Get a pair of iterators for the range of visible elements in a container. More...
template<typename Tcontainer >
auto	GetScrolledItemFromWidget (Tcontainer &container, int clickpos, const Window *const w, WidgetID widget, int padding=0, int line_height=-1) const
	Return an iterator pointing to the element of a scrolled widget that a user clicked in. More...
EventState	UpdateListPositionOnKeyPress (int &list_position, uint16_t keycode) const
	Update the given list position as if it were on this scroll bar when the given keycode was pressed. More...

Static Public Attributes
static constexpr size_type	max_size_type = std::numeric_limits<size_type>::max()
static constexpr size_type	npos = max_size_type

Private Attributes
const bool	is_vertical
	Scrollbar has vertical orientation.
size_type	count
	Number of elements in the list.
size_type	cap
	Number of visible elements of the scroll bar.
size_type	pos
	Index of first visible item of the list.
size_type	stepsize
	Distance to scroll, when pressing the buttons or using the wheel.

Detailed Description

Scrollbar data structure.

Definition at line 696 of file widget_type.h.

Member Enumeration Documentation

ScrollbarStepping

enum Scrollbar::ScrollbarStepping

Stepping sizes when scrolling.

Enumerator
SS_RAW	Step in single units.
SS_SMALL	Step in stepsize units.
SS_BIG	Step in cap units.

Definition at line 710 of file widget_type.h.

Member Function Documentation

GetCapacity()

size_type Scrollbar::GetCapacity ( ) const

inline

Gets the number of visible elements of the scrollbar.

Returns

the number of visible elements

Definition at line 733 of file widget_type.h.

References cap.

Referenced by DispatchMouseWheelEvent(), GoalListWindow::DrawListColumn(), NewGRFInspectWindow::DrawString(), GetVisibleRangeIterators(), HandleScrollbarHittest(), IsVisible(), ScrollTowards(), and ScriptDebugWindow::UpdateLogScroll().

GetCount()

size_type Scrollbar::GetCount ( ) const

inline

Gets the number of elements in the list.

Returns

the number of elements

Definition at line 724 of file widget_type.h.

References count.

Referenced by DispatchMouseWheelEvent(), GetScrolledItemFromWidget(), GetScrolledRowFromWidget(), GetVisibleRangeIterators(), HandleScrollbarHittest(), NewGRFParametersWindow::OnInvalidateData(), StoryBookWindow::OnPaint(), and ScriptDebugWindow::UpdateLogScroll().

GetPosition()

size_type Scrollbar::GetPosition ( ) const

inline

Gets the position of the first visible element in the list.

Returns

the position of the element

Definition at line 742 of file widget_type.h.

References pos.

Referenced by IndustryCargoesWindow::CalculatePositionInWidget(), ScriptDebugWindow::ChangeToScript(), TextfileWindow::CheckHyperlinkClick(), TimetableWindow::DrawArrivalDeparturePanel(), GoalListWindow::DrawListColumn(), NewGRFInspectWindow::DrawString(), TimetableWindow::DrawTimetablePanel(), GetScrolledRowFromWidget(), NWidgetMatrix::GetScrollOffsets(), GetVisibleRangeIterators(), HandleScrollbarHittest(), IsVisible(), ScrollTowards(), NWidgetMatrix::SetClicked(), TextfileWindow::UpdateHistoryScrollpos(), and ScriptDebugWindow::UpdateLogScroll().

GetScrolledItemFromWidget()

template<typename Tcontainer >

auto Scrollbar::GetScrolledItemFromWidget ( Tcontainer &  container, int  clickpos, const Window *const  w, WidgetID  widget, int  padding = 0, int  line_height = -1  ) const

inline

Return an iterator pointing to the element of a scrolled widget that a user clicked in.

Parameters

container	Container of elements represented by the scrollbar.
clickpos	Vertical position of the mouse click (without taking scrolling into account).
w	The window the click was in.
widget	Widget number of the widget clicked in.
padding	Amount of empty space between the widget edge and the top of the first row. Default value is 0.
line_height	Height of a single row. A negative value means using the vertical resize step of the widget.

Returns

Iterator to the element clicked at. If clicked at a wrong position, returns as interator to the end of the container.

Definition at line 881 of file widget_type.h.

References GetCount(), and GetScrolledRowFromWidget().

GetScrolledRowFromWidget()

Scrollbar::size_type Scrollbar::GetScrolledRowFromWidget	(	int	clickpos,
		const Window *const	w,
		WidgetID	widget,
		int	padding = 0,
		int	line_height = -1
	)		const

Compute the row of a scrolled widget that a user clicked in.

Parameters

clickpos	Vertical position of the mouse click (without taking scrolling into account).
w	The window the click was in.
widget	Widget number of the widget clicked in.
padding	Amount of empty space between the widget edge and the top of the first row. Default value is 0.
line_height	Height of a single row. A negative value means using the vertical resize step of the widget.

Returns

Row number clicked at. If clicked at a wrong position, #Scrollbar::npos is returned.

Definition at line 2320 of file widget.cpp.

References GetCount(), GetPosition(), Window::GetRowFromWidget(), and pos.

Referenced by NetworkClientListWindow::GetButtonAtPoint(), and GetScrolledItemFromWidget().

GetVisibleRangeIterators()

template<typename Tcontainer >

auto Scrollbar::GetVisibleRangeIterators ( Tcontainer &  container ) const

inline

Get a pair of iterators for the range of visible elements in a container.

Parameters

container

Container of elements represented by the scrollbar.

Returns

Pair of iterators of visible elements.

Definition at line 862 of file widget_type.h.

References GetCapacity(), GetCount(), and GetPosition().

Referenced by DrawEngineList(), and NetworkContentListWindow::DrawMatrix().

IsVertical()

bool Scrollbar::IsVertical ( ) const

inline

Is the scrollbar vertical or not?

Returns

True iff the scrollbar is vertical.

Definition at line 761 of file widget_type.h.

References is_vertical.

Referenced by NWidgetMatrix::GetScrollOffsets(), SetCapacityFromWidget(), and NWidgetMatrix::SetCount().

IsVisible()

bool Scrollbar::IsVisible ( size_type  item ) const

inline

Checks whether given current item is visible in the list.

Parameters

item

to check

Returns

true iff the item is visible

Definition at line 752 of file widget_type.h.

References GetCapacity(), GetPosition(), and IsInsideBS().

Referenced by TimetableWindow::DrawArrivalDeparturePanel(), and OrdersWindow::OnInvalidateData().

ScrollTowards()

void Scrollbar::ScrollTowards ( size_type  position )

inline

Scroll towards the given position; if the item is visible nothing happens, otherwise it will be shown either at the bottom or top of the window depending on where in the list it was.

Parameters

position

the position to scroll towards.

Definition at line 843 of file widget_type.h.

References GetCapacity(), GetPosition(), and SetPosition().

Referenced by ReplaceVehicleWindow::GenerateLists(), OrdersWindow::OnInvalidateData(), NetworkContentListWindow::ScrollToSelected(), VehicleGroupWindow::SelectGroup(), NWidgetMatrix::SetClicked(), and NewGRFWindow::UpdateScrollBars().

SetCapacity()

void Scrollbar::SetCapacity ( size_t  capacity )

inline

Set the capacity of visible elements.

Parameters

capacity

the new capacity

Note

updates the position if needed

Definition at line 796 of file widget_type.h.

References SetPosition().

Referenced by DepotWindow::OnResize(), SetCapacityFromWidget(), NWidgetMatrix::SetCount(), and DropdownWindow::UpdateSizeAndPosition().

SetCapacityFromWidget()

void Scrollbar::SetCapacityFromWidget	(	Window *	w,
		WidgetID	widget,
		int	padding = 0
	)

Set capacity of visible elements from the size and resize properties of a widget.

Parameters

w	Window.
widget	Widget with size and resize properties.
padding	Padding to subtract from the size.

Note

Updates the position if needed.

Definition at line 2394 of file widget.cpp.

References NWidgetBase::current_x, NWidgetBase::current_y, Window::GetWidget(), IsVertical(), NWidgetBase::resize_x, NWidgetBase::resize_y, and SetCapacity().

Referenced by TextfileWindow::OnResize(), PickerWindow::OnResize(), ScriptListWindow::OnResize(), SubsidyListWindow::OnResize(), SignListWindow::OnResize(), GoalListWindow::OnResize(), BuildBridgeWindow::OnResize(), GSConfigWindow::OnResize(), NewGRFParametersWindow::OnResize(), ScriptSettingsWindow::OnResize(), NewGRFInspectWindow::OnResize(), ReplaceVehicleWindow::OnResize(), BuildIndustryWindow::OnResize(), CompanyStationsWindow::OnResize(), TimetableWindow::OnResize(), StoryBookWindow::OnResize(), NewGRFWindow::OnResize(), SaveLoadWindow::OnResize(), NetworkGameWindow::OnResize(), NetworkContentListWindow::OnResize(), SelectCompanyLiveryWindow::OnResize(), VehicleGroupWindow::OnResize(), TownDirectoryWindow::OnResize(), PaymentRatesGraphWindow::OnResize(), DepotWindow::OnResize(), SpriteAlignerWindow::OnResize(), MessageHistoryWindow::OnResize(), ScriptDebugWindow::OnResize(), RefitWindow::OnResize(), OrdersWindow::OnResize(), NetworkClientListWindow::OnResize(), IndustryDirectoryWindow::OnResize(), BuildVehicleWindow::OnResize(), StationViewWindow::OnResize(), SavePresetWindow::OnResize(), VehicleListWindow::OnResize(), SelectStationWindow< T >::OnResize(), VehicleDetailsWindow::OnResize(), GameSettingsWindow::OnResize(), and IndustryCargoesWindow::OnResize().

SetCount()

void Scrollbar::SetCount ( size_t  num )

inline

Sets the number of elements in the list.

Parameters

num	the number of elements in the list

Note

updates the position if needed

Definition at line 782 of file widget_type.h.

References SetPosition().

Referenced by NetworkContentListWindow::BuildContentList(), PickerWindow::BuildPickerClassList(), IndustryDirectoryWindow::BuildSortIndustriesList(), CompanyStationsWindow::BuildStationsList(), IndustryCargoesWindow::ComputeCargoDisplay(), IndustryCargoesWindow::ComputeIndustryDisplay(), ReplaceVehicleWindow::GenerateLists(), SubsidyListWindow::OnInvalidateData(), GoalListWindow::OnInvalidateData(), NewGRFParametersWindow::OnInvalidateData(), OrdersWindow::OnInvalidateData(), SpriteAlignerWindow::OnInvalidateData(), ScriptDebugWindow::OnInvalidateData(), MessageHistoryWindow::OnInvalidateData(), SelectStationWindow< T >::OnInvalidateData(), GameSettingsWindow::OnInvalidateData(), TimetableWindow::OnPaint(), VehicleGroupWindow::OnPaint(), StoryBookWindow::OnPaint(), RefitWindow::OnPaint(), StationViewWindow::OnPaint(), BuildVehicleWindow::OnPaint(), VehicleDetailsWindow::OnPaint(), StoryBookWindow::OnResize(), GSConfigWindow::RebuildVisibleSettings(), ScriptSettingsWindow::RebuildVisibleSettings(), StoryBookWindow::RefreshSelectedPage(), SavePresetWindow::SavePresetWindow(), ScriptListWindow::ScriptListWindow(), BuildAirportWindow::SelectFirstAvailableAirport(), VehicleGroupWindow::SelectGroup(), NWidgetMatrix::SetCount(), TextfileWindow::SetupScrollbars(), ScriptDebugWindow::UpdateLogScroll(), NewGRFWindow::UpdateScrollBars(), and DropdownWindow::UpdateSizeAndPosition().

SetPosition()

bool Scrollbar::SetPosition ( size_type  position )

inline

Sets the position of the first visible element.

Parameters

position

the position of the element

Returns

true iff the position has changed

Definition at line 812 of file widget_type.h.

References Clamp(), and pos.

Referenced by ReplaceVehicleWindow::OnRailRoadTypeChange(), ScrollTowards(), SetCapacity(), SetCount(), ScriptDebugWindow::UpdateLogScroll(), and UpdatePosition().

SetStepSize()

void Scrollbar::SetStepSize ( size_t  stepsize )

inline

Set the distance to scroll when using the buttons or the wheel.

Parameters

stepsize

Scrolling speed.

Definition at line 770 of file widget_type.h.

References stepsize.

Referenced by ScriptDebugWindow::ScriptDebugWindow(), and NWidgetMatrix::SetCount().

UpdateListPositionOnKeyPress()

EventState Scrollbar::UpdateListPositionOnKeyPress	(	int &	list_position,
		uint16_t	keycode
	)		const

Update the given list position as if it were on this scroll bar when the given keycode was pressed.

This does not update the actual position of this scroll bar, that is left to the caller. It does, however use the capacity and count of the scroll bar for the bounds and amount to scroll.

When the count is 0 or the return is ES_NOT_HANDLED, then the position is not updated. With WKC_UP and WKC_DOWN the position goes one up or down respectively. With WKC_PAGEUP and WKC_PAGEDOWN the position goes one capacity up or down respectively. With WKC_HOME the first position is selected and with WKC_END the last position is selected. This function ensures that pos is in the range [0..count).

Parameters

list_position	The current position in the list.
key_code	The pressed key code.

Returns

ES_NOT_HANDLED when another key than the 6 specific keys was pressed, otherwise ES_HANDLED.

Definition at line 2341 of file widget.cpp.

UpdatePosition()

bool Scrollbar::UpdatePosition ( int  difference, ScrollbarStepping  unit = SS_SMALL  )

inline

Updates the position of the first visible element by the given amount.

If the position would be too low or high it will be clamped appropriately

Parameters

difference	the amount of change requested
unit	The stepping unit of difference

Returns

true iff the position has changed

Definition at line 826 of file widget_type.h.

References cap, SetPosition(), SS_BIG, SS_SMALL, and stepsize.

Referenced by DispatchMouseWheelEvent(), and DropdownWindow::UpdateSizeAndPosition().

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The documentation for this class was generated from the following files:

• src/widget_type.h
• src/widget.cpp