#include <hikogui/widgets/widget.hpp>

Inheritance diagram for hi::v1::widget:

Public Member Functions
	widget (widget *parent) noexcept

	widget (const widget &)=delete

widget &	operator= (const widget &)=delete

	widget (widget &&)=delete

widget &	operator= (widget &&)=delete

virtual generator< widget const & >	children (bool include_invisible) const noexcept
	Get a list of child widgets.

generator< widget & >	children (bool include_invisible) noexcept

virtual hitbox	hitbox_test (point2i position) const noexcept
	Find the widget that is under the mouse cursor.

virtual hitbox	hitbox_test_from_parent (point2i position) const noexcept
	Call hitbox_test from a parent widget.

virtual hitbox	hitbox_test_from_parent (point2i position, hitbox sibling_hitbox) const noexcept
	Call hitbox_test from a parent widget.

virtual bool	accepts_keyboard_focus (keyboard_focus_group group) const noexcept
	Check if the widget will accept keyboard focus.

virtual box_constraints	update_constraints () noexcept
	Update the constraints of the widget.

virtual void	set_layout (widget_layout const &context) noexcept
	Update the internal layout of the widget.

widget_layout const &	layout () const noexcept
	Get the current layout for this widget.

virtual void	draw (draw_context const &context) noexcept
	Draw the widget.

virtual bool	process_event (gui_event const &event) const noexcept

virtual void	request_redraw () const noexcept
	Request the widget to be redrawn on the next frame.

virtual bool	handle_event (gui_event const &event) noexcept
	Handle command.

virtual bool	handle_event_recursive (gui_event const &event, std::vector< widget_id > const &reject_list=std::vector< widget_id >{}) noexcept
	Handle command recursive.

virtual widget_id	find_next_widget (widget_id current_keyboard_widget, keyboard_focus_group group, keyboard_focus_direction direction) const noexcept
	Find the next widget that handles keyboard focus.

widget_id	find_first_widget (keyboard_focus_group group) const noexcept

widget_id	find_last_widget (keyboard_focus_group group) const noexcept

bool	is_first (keyboard_focus_group group) const noexcept
	Is this widget the first widget in the parent container.

bool	is_last (keyboard_focus_group group) const noexcept
	Is this widget the last widget in the parent container.

virtual void	scroll_to_show (hi::aarectanglei rectangle) noexcept
	Scroll to show the given rectangle on the window.

void	scroll_to_show () noexcept
	Scroll to show the important part of the widget.

std::vector< widget_id >	parent_chain () const noexcept
	Get a list of parents of a given widget.

virtual gui_window *	window () const noexcept

virtual hi::theme const &	theme () const noexcept

virtual gfx_surface const *	surface () const noexcept

virtual color	background_color () const noexcept

virtual color	foreground_color () const noexcept

virtual color	focus_color () const noexcept

virtual color	accent_color () const noexcept

virtual color	label_color () const noexcept

Public Member Functions inherited from std::enable_shared_from_this< widget >
T	enable_shared_from_this (T... args)

T	operator= (T... args)

T	shared_from_this (T... args)

T	~enable_shared_from_this (T... args)

Data Fields
widget *	parent = nullptr
	Pointer to the parent widget.

widget_id	id = {}
	The numeric identifier of a widget.

observer< widget_mode >	mode = widget_mode::enabled
	The widget mode.

observer< bool >	hover = false
	Mouse cursor is hovering over the widget.

observer< bool >	focus = false
	The widget has keyboard focus.

int	semantic_layer = 0
	The draw layer of the widget.

int	logical_layer = 0
	The logical layer of the widget.

observer< extent2i >	minimum = extent2i{}
	The minimum size this widget is allowed to be.

observer< extent2i >	maximum = extent2i::large()
	The maximum size this widget is allowed to be.

Detailed Description

An interactive graphical object as part of the user-interface.

Rendering is done in three distinct phases:

Updating Constraints: widget::update_constraints()
Updating Layout: widget::set_layout()
Drawing: widget::draw()

Constructor & Destructor Documentation

◆ widget()

hi::v1::widget::widget ( widget * parent )

explicitnoexcept

Constructor for creating sub views.

Member Function Documentation

◆ accepts_keyboard_focus()

virtual bool hi::v1::widget::accepts_keyboard_focus ( keyboard_focus_group group ) const

inlinevirtualnoexcept

Check if the widget will accept keyboard focus.

Reimplemented in hi::v1::scroll_bar_widget< Axis >.

◆ children()

virtual generator< widget const & > hi::v1::widget::children ( bool include_invisible ) const

inlinevirtualnoexcept

Get a list of child widgets.

Reimplemented in hi::v1::spacer_widget.

◆ draw()

virtual void hi::v1::widget::draw ( draw_context const & context )

inlinevirtualnoexcept

Draw the widget.

This function is called by the window (optionally) on every frame. It should recursively call this function on every visible child. This function is only called when updateLayout() has returned true.

The overriding function should call the base class's draw(), the place where the call this function will determine the order of the vertices into each buffer. This is important when needing to do the painters algorithm for alpha-compositing. However the pipelines are always drawn in the same order.

Parameters

context The context to where the widget will draw.

Reimplemented in hi::v1::scroll_bar_widget< Axis >, and hi::v1::spacer_widget.

◆ find_next_widget()

virtual widget_id hi::v1::widget::find_next_widget	(	widget_id	current_keyboard_widget,
		keyboard_focus_group	group,
		keyboard_focus_direction	direction ) const

virtualnoexcept

Find the next widget that handles keyboard focus.

This recursively looks for the current keyboard widget, then returns the next (or previous) widget that returns true from accepts_keyboard_focus().

Parameters

current_keyboard_widget	The widget that currently has focus; or nullptr to get the first widget that accepts focus.
group	The group to which the widget must belong.
direction	The direction in which to walk the widget tree.

Returns: A pointer to the next widget.

Return values

current_keyboard_widget	When current_keyboard_widget was found but no next widget that accepts keyboard focus was found.
nullptr	When current_keyboard_widget is not found in this widget.

◆ handle_event()

virtual bool hi::v1::widget::handle_event ( gui_event const & event )

virtualnoexcept

Handle command.

If a widget does not fully handle a command it should pass the command to the super class' handle_event().

Reimplemented in hi::v1::scroll_bar_widget< Axis >.

◆ handle_event_recursive()

virtual bool hi::v1::widget::handle_event_recursive	(	gui_event const &	event,
		std::vector< widget_id > const &	reject_list = std::vector< widget_id >{} )

virtualnoexcept

Handle command recursive.

Handle a command and pass it to each child.

Parameters

event	The command to handle by this widget.
reject_list	The widgets that should ignore this command

Returns: True when the command was handled by this widget or recursed child.

◆ hitbox_test()

virtual hitbox hi::v1::widget::hitbox_test ( point2i position ) const

inlinevirtualnoexcept

Find the widget that is under the mouse cursor.

This function will recursively test with visual child widgets, when widgets overlap on the screen the hitbox object with the highest elevation is returned.

Parameters

position The coordinate of the mouse local to the widget.

Returns: A hit_box object with the cursor-type and a reference to the widget.

Reimplemented in hi::v1::scroll_bar_widget< Axis >, and hi::v1::spacer_widget.

◆ hitbox_test_from_parent() [1/2]

virtual hitbox hi::v1::widget::hitbox_test_from_parent ( point2i position ) const

inlinevirtualnoexcept

Call hitbox_test from a parent widget.

This function will transform the position from parent coordinates to local coordinates.

Parameters

position The coordinate of the mouse local to the parent widget.

◆ hitbox_test_from_parent() [2/2]

virtual hitbox hi::v1::widget::hitbox_test_from_parent	(	point2i	position,
		hitbox	sibling_hitbox ) const

inlinevirtualnoexcept

Call hitbox_test from a parent widget.

This function will transform the position from parent coordinates to local coordinates.

Parameters

position	The coordinate of the mouse local to the parent widget.
sibling_hitbox	The hitbox of a sibling to combine with the hitbox of this widget.

◆ is_first()

bool hi::v1::widget::is_first ( keyboard_focus_group group ) const

noexcept

Is this widget the first widget in the parent container.

◆ is_last()

bool hi::v1::widget::is_last ( keyboard_focus_group group ) const

noexcept

Is this widget the last widget in the parent container.

◆ layout()

widget_layout const & hi::v1::widget::layout ( ) const

inlinenoexcept

Get the current layout for this widget.

◆ parent_chain()

std::vector< widget_id > hi::v1::widget::parent_chain ( ) const

noexcept

Get a list of parents of a given widget.

The chain includes the given widget.

◆ request_redraw()

virtual void hi::v1::widget::request_redraw ( ) const

inlinevirtualnoexcept

Request the widget to be redrawn on the next frame.

Reimplemented in hi::v1::toolbar_tab_button_widget.

◆ scroll_to_show() [1/2]

void hi::v1::widget::scroll_to_show ( )

inlinenoexcept

Scroll to show the important part of the widget.

◆ scroll_to_show() [2/2]

virtual void hi::v1::widget::scroll_to_show ( hi::aarectanglei rectangle )

virtualnoexcept

Scroll to show the given rectangle on the window.

This will call parents, until all parents have scrolled the rectangle to be shown on the window.

Parameters

rectangle The rectangle in window coordinates.

◆ set_layout()

virtual void hi::v1::widget::set_layout ( widget_layout const & context )

inlinevirtualnoexcept

Update the internal layout of the widget.

This function is called when the size of this widget must change, or if any of the widget request a re-layout.

This function may be used for expensive calculations, such as geometry calculations, which should only be done when the data or sizes change; it should cache these calculations.

Postcondition: This function will change what is returned by widget::size() and the transformation matrices.

Parameters

context The layout for this child.

Reimplemented in hi::v1::scroll_bar_widget< Axis >, and hi::v1::spacer_widget.

◆ update_constraints()

virtual box_constraints hi::v1::widget::update_constraints ( )

inlinevirtualnoexcept

Update the constraints of the widget.

Typically the implementation of this function starts with recursively calling update_constraints() on its children.

If the container, due to a change in constraints, wants the window to resize to the minimum size it should call request_resize().

Postcondition: This function will change what is returned by widget::minimum_size(), widget::preferred_size() and widget::maximum_size().

Reimplemented in hi::v1::scroll_bar_widget< Axis >, and hi::v1::spacer_widget.

Field Documentation

◆ focus

observer<bool> hi::v1::widget::focus = false

The widget has keyboard focus.

◆ hover

observer<bool> hi::v1::widget::hover = false

Mouse cursor is hovering over the widget.

◆ id

widget_id hi::v1::widget::id = {}

The numeric identifier of a widget.

Note: This is a uint32_t equal to the operating system's accessibility identifier.

◆ logical_layer

int hi::v1::widget::logical_layer = 0

The logical layer of the widget.

The logical layer can be used to determine how far away from the window-widget (root) the current widget is.

Logical layers start at 0 for the window-widget. Each child widget increases the logical layer by 1.

◆ maximum

observer<extent2i> hi::v1::widget::maximum = extent2i::large()

The maximum size this widget is allowed to be.

◆ minimum

observer<extent2i> hi::v1::widget::minimum = extent2i{}

The minimum size this widget is allowed to be.

◆ mode

observer<widget_mode> hi::v1::widget::mode = widget_mode::enabled

The widget mode.

The current visibility and interactivity of a widget.

◆ parent

widget* hi::v1::widget::parent = nullptr

Pointer to the parent widget.

May be a nullptr only when this is the top level widget.

◆ semantic_layer

int hi::v1::widget::semantic_layer = 0

The draw layer of the widget.

The semantic layer is used mostly by the draw() function for selecting colors from the theme, to denote nesting widgets inside other widgets.

Semantic layers start at 0 for the window-widget and for any pop-up widgets.

The semantic layer is increased by one, whenever a user of the user-interface would understand the next layer to begin.

In most cases it would mean that a container widget that does not draw itself will not increase the semantic_layer number.

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

hikogui/src/hikogui/widgets/widget.hpp

Public Member Functions

Data Fields

Detailed Description

Constructor & Destructor Documentation

◆ widget()

Member Function Documentation

◆ accepts_keyboard_focus()

◆ children()

◆ draw()

◆ find_next_widget()

◆ handle_event()

◆ handle_event_recursive()

◆ hitbox_test()

◆ hitbox_test_from_parent() [1/2]

◆ hitbox_test_from_parent() [2/2]

◆ is_first()

◆ is_last()

◆ layout()

◆ parent_chain()

◆ request_redraw()

◆ scroll_to_show() [1/2]

◆ scroll_to_show() [2/2]

◆ set_layout()

◆ update_constraints()

Field Documentation

◆ focus

◆ hover

◆ id

◆ logical_layer

◆ maximum

◆ minimum

◆ mode

◆ parent

◆ semantic_layer