FlexBox Class Reference

Represents a FlexBox container, which contains and manages the layout of a set of FlexItem objects. More...

Public Types
enum class	Direction { row , rowReverse , column , columnReverse }
	Possible values for the flexDirection property. More...
enum class	Wrap { noWrap , wrap , wrapReverse }
	Possible values for the flexWrap property. More...
enum class	AlignContent {   stretch , flexStart , flexEnd , center ,   spaceBetween , spaceAround }
	Possible values for the alignContent property. More...
enum class	AlignItems { stretch , flexStart , flexEnd , center }
	Possible values for the alignItems property. More...
enum class	JustifyContent {   flexStart , flexEnd , center , spaceBetween ,   spaceAround }
	Possible values for the justifyContent property. More...

Public Member Functions
	FlexBox () noexcept=default
	Creates an empty FlexBox container with default parameters.
	FlexBox (Direction, Wrap, AlignContent, AlignItems, JustifyContent) noexcept
	Creates an empty FlexBox container with these parameters.
	FlexBox (JustifyContent) noexcept
	Creates an empty FlexBox container with the given content-justification mode.
void	performLayout (Rectangle< float > targetArea)
	Lays-out the box's items within the given rectangle.
void	performLayout (Rectangle< int > targetArea)
	Lays-out the box's items within the given rectangle.

Public Attributes
Direction	flexDirection = Direction::row
	Specifies how flex items are placed in the flex container, and defines the direction of the main axis.
Wrap	flexWrap = Wrap::noWrap
	Specifies whether items are forced into a single line or can be wrapped onto multiple lines.
AlignContent	alignContent = AlignContent::stretch
	Specifies how a flex container's lines are placed within the flex container when there is extra space on the cross-axis.
AlignItems	alignItems = AlignItems::stretch
	Specifies the alignment of flex items along the cross-axis of each line.
JustifyContent	justifyContent = JustifyContent::flexStart
	Defines how the container distributes space between and around items along the main-axis.
Array< FlexItem >	items
	The set of items to lay-out.

Detailed Description

Represents a FlexBox container, which contains and manages the layout of a set of FlexItem objects.

To use this class, set its parameters appropriately (you can search online for more help on exactly how the FlexBox protocol works!), then add your sub-items to the items array, and call performLayout() in the resized() function of your Component.

See also

FlexItem

Member Enumeration Documentation

Direction

enum class FlexBox::Direction

strong

Possible values for the flexDirection property.

Enumerator
row	Set the main axis direction from left to right.
rowReverse	Set the main axis direction from right to left.
column	Set the main axis direction from top to bottom.
columnReverse	Set the main axis direction from bottom to top.

Wrap

enum class FlexBox::Wrap

strong

Possible values for the flexWrap property.

Enumerator
noWrap	Items are forced into a single line.
wrap	Items are wrapped onto multiple lines from top to bottom.
wrapReverse	Items are wrapped onto multiple lines from bottom to top.

AlignContent

enum class FlexBox::AlignContent

strong

Possible values for the alignContent property.

Enumerator
stretch	Lines of items are stretched from start to end of the cross axis.
flexStart	Lines of items are aligned towards the start of the cross axis.
flexEnd	Lines of items are aligned towards the end of the cross axis.
center	Lines of items are aligned towards the center of the cross axis.
spaceBetween	Lines of items are evenly spaced along the cross axis with spaces between them.
spaceAround	Lines of items are evenly spaced along the cross axis with spaces around them.

AlignItems

enum class FlexBox::AlignItems

strong

Possible values for the alignItems property.

Enumerator
stretch	Items are stretched from start to end of the cross axis.
flexStart	Items are aligned towards the start of the cross axis.
flexEnd	Items are aligned towards the end of the cross axis.
center	Items are aligned towards the center of the cross axis.

JustifyContent

enum class FlexBox::JustifyContent

strong

Possible values for the justifyContent property.

Enumerator
flexStart	Items are justified towards the start of the main axis.
flexEnd	Items are justified towards the end of the main axis.
center	Items are justified towards the center of the main axis.
spaceBetween	Items are evenly spaced along the main axis with spaces between them.
spaceAround	Items are evenly spaced along the main axis with spaces around them.

Constructor & Destructor Documentation

FlexBox() [1/3]

FlexBox::FlexBox ( )

defaultnoexcept

Creates an empty FlexBox container with default parameters.

FlexBox() [2/3]

FlexBox::FlexBox ( Direction , Wrap , AlignContent , AlignItems , JustifyContent  )

noexcept

Creates an empty FlexBox container with these parameters.

FlexBox() [3/3]

FlexBox::FlexBox ( JustifyContent )

noexcept

Creates an empty FlexBox container with the given content-justification mode.

Member Function Documentation

performLayout() [1/2]

void FlexBox::performLayout

(

Rectangle< float >

targetArea

)

Lays-out the box's items within the given rectangle.

performLayout() [2/2]

void FlexBox::performLayout

(

Rectangle< int >

targetArea

)

Lays-out the box's items within the given rectangle.

Member Data Documentation

flexDirection

Direction FlexBox::flexDirection = Direction::row

Specifies how flex items are placed in the flex container, and defines the direction of the main axis.

flexWrap

Wrap FlexBox::flexWrap = Wrap::noWrap

Specifies whether items are forced into a single line or can be wrapped onto multiple lines.

If wrapping is allowed, this property also controls the direction in which lines are stacked.

alignContent

AlignContent FlexBox::alignContent = AlignContent::stretch

Specifies how a flex container's lines are placed within the flex container when there is extra space on the cross-axis.

This property has no effect on single line layouts.

alignItems

AlignItems FlexBox::alignItems = AlignItems::stretch

Specifies the alignment of flex items along the cross-axis of each line.

justifyContent

JustifyContent FlexBox::justifyContent = JustifyContent::flexStart

Defines how the container distributes space between and around items along the main-axis.

The alignment is done after the lengths and auto margins are applied, so that if there is at least one flexible element, with flex-grow different from 0, it will have no effect as there won't be any available space.

items

Array<FlexItem> FlexBox::items

The set of items to lay-out.