builds React UI

A library of React components that abstract over HTML and CSS, for building UIs from high-level, simple expressions.

Inspired by elm-ui.

API

mount

mount_to_body (options) (layout_box)

Mounts a layout box to the dom body, within a Stack.

Options are not implemented yet, so pass an empty object.

Layout boxes

Layout boxes are 2d boxes that may contain text or other layout boxes.

Box

Box may have only one child and is no different from a Column or Row with a single child.

Column

Column lays out its children across the Y axis (vertical).

Row

Row lays out its children across the X axis (horizontal).

Layout box props

anchor_x={[ number, number ]}, anchor_y={[ number, number ]}

These properties only apply to relatives.

default: [ 0, 0 ]

The first number represents a point on the relative box, and the second number represents a point on the origin box. 0 refers to the start of the box along the axis, and 1 refers to the end of the box along the axis. anchor_x={[ 0.5, 1 ]} means to position the horizontal center (0.5) of the relative box on the right (1) of the origin box.

<Row
	foreground={[
		<Box anchor_x={[ 0.5, 0.5 ]} anchor_y={[ 0.5, 0.5 ]}>
			This box is horizontally and vertically centered in the row and in front of the row's children.
		</Box>
	]}
>
	{children}
</Row>

ascended={[layout_boxes]}

Place components relatively close to the front of the current Stack.

See Stack and relatives.

background={[layout_boxes]}

Place components behind children.

See relatives.

class_name={string}

Apply class attribute to the underlying dom node.

descended={[layout_boxes]}

Place components relatively close to the back of the current Stack.

See Stack and relatives.

element_props={object}

Pass props to the underlying React element. This prop is a temporary approach to accessing some behavior not yet available through this library's API.

<Box element_props={{ onClick: handle_the_click }}></Box>

foreground={[layout_boxes]}

Place components in front of children.

See relatives.

height={length}

default: content

See length.

width={length}

default: content

See length.

layout_x={layout}

See layout.

default: align.start

layout_y={layout}

See layout.

default: align.start

padding={{ bottom = 0, left = 0, right = 0, top = 0 }}

Apply padding to the inner edges of the box. For convenience, use edges (n), edges.x (n) edges.y (n), and edges.xy (nx) (ny).

import { Box, edges } from '#ui'

<Box padding={{ left: 10 }}></Box>

{/* These are equivalent: */}
<Box padding={{ left: 10, right: 10 }}></Box>
<Box padding={edges.x (10)}></Box>

{/* These are equivalent: */}
<Box padding={{ top: 10, bottom: 10 }}></Box>
<Box padding={edges.y (10)}></Box>

{/* These are equivalent: */}
<Box padding={{ bottom: 20, left: 10, right: 10, top: 20 }}></Box>
<Box padding={edges.xy (10) (20)}></Box>

{/* These are equivalent: */}
<Box padding={{ bottom: 10, left: 10, right: 10, top: 10 }}></Box>
<Box padding={edges (10)}></Box>

offset_x={number}

offset_x arbitrarily moves a box along the x axis by the given number of pixels. The layout the box is within is unaffected; it is as though the box is in its original position.

offset_y={number}

offset_y arbitrarily moves a box along the x axis by the given number of pixels. The layout the box is within is unaffected; it is as though the box is in its original position.

overflow={overflow}

See overflow.

default: overflow.visible

Configures the handling of overflow, which is when a box's content exceeds its bounds.

style={{ [property]: value }}

Apply inline styles to the underlying dom node. See React's style prop.

tag={string}

default: 'div'

The tag name to use to create the underlying dom node.

edges

edges (number)

Shorthand for { bottom: number, left: number, right: number, top: number }.

edges.x (number)

Shorthand for { left: number, right: number }.

edges.y (number)

Shorthand for { bottom: number, top: number }.

edges.xy (number_x) (number_y)

Shorthand for { bottom: number_y, left: number_x, right: number_x, top: number_y }.

layout

gap is a number of pixels of space on the layout axis between layout children.

align.start, align.start ({ gap: number })

Layout children from the start of the layout axis (top edge of column, left edge of row).

align.start is shorthand for align.start ({ gap: 0 }).

align.center, align.start ({ gap: number })

Layout children from the center of the layout axis (children or centered on the axis).

align.center is shorthand for align.center ({ gap: 0 }).

align.end, align.end ({ gap: number })

Layout children from the end of the layout axis (botton edge of column, right edge of row).

align.end is shorthand for align.end ({ gap: 0 }).

align.space_around

Distribute equal space on each side of layout children.

align.space_between

Distribute equal space between layout children.

align.space_evenly

Distribute equal space around layout children.

length

These are values that can be provided as height and width. For convenience, a number can be passed as a length, and it will be interpreted as a number of px.

"Content" refers to what is in a box, also known as its "layout child(ren)".

"Remaining length" refers to the parent length minus the lengths specifically claimed by its children (px lengths, grow and content content lengths).

px (number)

A number of pixels.

ratio (number)

A ratio of the parent length not derived from its content.

import { Box, Row, ratio } from '#ui'

<Box height={100}>
	{/* The following box has a height of 50px (100 * 0.5). */}
	<Box height={ratio(0.5)}></Box>
</Box>

Because content and grow lengths are computed from content, a ratio of a content or grow length parent is always 0.

<Row height={content} width={content}>
	<Box height={100} width={100}></Box>
	{/* The following box has a height and width of 0, because its parent's height and width are `content` */}
	<Box height={ratio(0.5)} width={ratio(0.5)}></Box>
</Row>

grow, grow ({ factor: number })

grow means to be at least the length of content plus a portion of remaining parent length, which is distributed according to factor. Siblings with grow ({ factor: 1 }) will grow by equal amounts.

grow is shorthand for grow ({ factor: 1 }).

content

content means to be same length as content (what is in the box). This is the default value for box height and width.

content is equivalent to grow ({ factor: 0 }).

expand, expand({ factor = 1 })

NOTE: expand does not work as a value of height on children of Column due to implementation difficulty. Help is welcome!

expand means the length is expanded by content, within a portion of parent length, which is distributed according to factor.

expand is shorthand for expand ({ factor: 1 })

fill, fill ({ factor = 1, maximum = Infinity })

fill means to have a length that is a portion of remaining parent length, which is distrubuted according to factor, but no greater than maximum.

fill is shorthand for fill ({ factor: 1, maximum: Infinity }).

overflow

Note that scroll_x hides overflow on the y axis and scroll_y hides overflow on the x axis. This is by necessity, as there cannot be overflow across a scrollbar.

overflow.clip

Hide all overflow.

overflow.clip_x

Hide overflow on the x axis.

overflow.clip_y

Hide overflow on the y axis.

overflow.scroll ({ overscroll = { x = overscroll_default, y = overscroll_default } })

All overflow is scrollable.

overflow.scroll_x ({ overscroll = overscroll_default })

Overflow on the x axis is scrollable. Overflow on the y axis is hidden.

overflow.scroll_y ({ overscroll = overscroll_default })

Overflow on the y axis is scrollable. Overflow on the x axis is hidden.

overflow.visible

Render all overflow. This is the default.

overscroll

overscroll configures scroll chaining and boundary default actions.

overscroll_default

Use the default scroll chaining and boundary default actions of the user agent.

overscroll_disabled

Disable scroll chaining and boundary default actions.

overscroll_contained

Disable scroll chaining. Boundary default actions local to the scroll container (e.g. overscroll glow effect) remain enabled.

relatives

A relative is a component that is expressed in the ascended, background, descended, or foreground properties of a layout box.

A relative is positioned and sized relative to the layout box (origin) on which it is expressed.

A relative has no effect on the size or position of its origin or its origin's children.

Relatives use properties anchor_x and anchor_y to express x and y position relative to the origin box.

import { Box } from '#ui'

{/* This box has a relative box that is horizontally and vertically centered, twice as tall, the same width, and behind its layout children.*/}
<Box
	background={[
		<Box anchor_x={[ 0.5, 0.5 ]} anchor_y={[ 0.5, 0.5 ]} height={ratio(2)} width={fill}></Box>
	]}
>
</Box>

{/* This box has a relative box that is the same height and width and in front of its layout children.*/}
<Box
	foreground={[
		<Box height={fill} width={fill}></Box>
	]}
>
</Box>

Stack

Stack is a span of z space, in which all children stack. Each successive child (including its children) is higher than the former (including its children).

Every layout box has a natural position in z space, above the box before it, and before the box after it. It can place other boxes in z space relative to its z position via its ascended, background, descended, and foreground properties. These further subdivide z space, and so do not conflict with the natural z stacking of boxes e.g. the foreground of a box is behind the background of its next sibling.

background is the z space before the box's children.

foreground is the z space after the box's children.

ascended expresses the intent for boxes to be as in front as possible without imposing exact opinions of 'how much in front'. This is conceptually similar to <Box width={fill}>, where the box expresses intent to take up as much width as possible, leaving the determination of how much width that is to the surrounding context. If from a higher view, you see that some ascended relatives should be restrained to a z space prior to others, you can wrap them in a Stack to specify the highest point in z space they can reach.

ascended is a nested Stack in the z space relatively close to the front of the most immediate Stack.

What is meant by "relatively close" is that how close it is to the front of the stack depends the z position of the origin box. If the first and second child of a stack ascend a relative, the second child's relative is closer to the front of the stack because the second child is closer to the front of the stack.

The ascended z space from a box is itself a Stack, so if box A ascends a box, A1, and box B ascends a box, B1, and A1 ascends a box, A1A, then A1A is not above B1, because A1 and A1A are in a stack that is below the stack containing B1.

descended is analogous to ascended, except it pertains to the back of the stack, rather than the front.

This depicts the relative z space positions a layout box can place components.

ascended<---
           |
           |
foreground |
         >--
children
         >--
background |
           |
           |
descended<--

This depicts the order of relative z space positions including complex combinations e.g. a box in the foreground with a descended box.

					foreground ascendants
				ascendants
			children ascendants
		background ascendants
	foreground
children
	background
		foreground descendants
			children descendants
				descendants
					background descendants

Many applications will likely have all their z position concerns handled with this pattern:

const App = () => {
	return <>
		<Stack>
			{/* most UI goes here */}
		</Stack>
		{/* modals and other such components go here */}
	</>
}