Box

The primary layout component. Uses Flexily for CSS-spec-compliant flexbox layout.

Import

import { Box } from "silvery"

Usage

<Box flexDirection="row" padding={1} borderStyle="single">
  <Text>Hello</Text>
  <Text>World</Text>
</Box>

Props

Layout - Flex Direction

Prop	Type	Default	Description
flexDirection	"row" | "column" | "row-reverse" | "column-reverse"	"column"	Main axis direction
flexWrap	"wrap" | "nowrap" | "wrap-reverse"	"nowrap"	Whether to wrap children
gap	number	0	Gap between children (in both directions)

Layout - Flex Item

Prop	Type	Default	Description
flexGrow	number	0	How much to grow relative to siblings
flexShrink	number	1	How much to shrink relative to siblings
flexBasis	number | string	-	Initial size before grow/shrink

Layout - Alignment

Prop	Type	Default	Description
alignItems	"flex-start" | "flex-end" | "center" | "stretch" | "baseline"	"stretch"	Cross-axis alignment of children
alignSelf	"auto" | "flex-start" | "flex-end" | "center" | "stretch" | "baseline"	"auto"	Override parent's alignItems
alignContent	"flex-start" | "flex-end" | "center" | "stretch" | "space-between" | "space-around"	-	Alignment of wrapped lines
justifyContent	"flex-start" | "flex-end" | "center" | "space-between" | "space-around" | "space-evenly"	"flex-start"	Main-axis alignment of children

Sizing

Prop	Type	Default	Description
width	number | string	-	Fixed width or percentage (e.g., "50%")
height	number | string	-	Fixed height or percentage
minWidth	number | string	-	Minimum width
minHeight	number | string	-	Minimum height
maxWidth	number | string	-	Maximum width
maxHeight	number | string	-	Maximum height

Spacing - Padding

Prop	Type	Default	Description
padding	number	0	Padding on all sides
paddingTop	number	0	Top padding
paddingBottom	number	0	Bottom padding
paddingLeft	number	0	Left padding
paddingRight	number	0	Right padding
paddingX	number	0	Horizontal padding (left + right)
paddingY	number	0	Vertical padding (top + bottom)

Spacing - Margin

Prop	Type	Default	Description
margin	number	0	Margin on all sides
marginTop	number	0	Top margin
marginBottom	number	0	Bottom margin
marginLeft	number	0	Left margin
marginRight	number	0	Right margin
marginX	number	0	Horizontal margin
marginY	number	0	Vertical margin

Position

Prop	Type	Default	Description
position	"relative" | "absolute" | "sticky"	"relative"	Positioning mode
stickyTop	number	0	Offset from top when sticky (only with position="sticky")
stickyBottom	number	-	Offset from bottom when sticky. Works in scroll containers and as a bottom-pinning primitive in any parent with explicit height.

Display

Prop	Type	Default	Description
display	"flex" | "none"	"flex"	Whether to display the element

Border

Prop	Type	Default	Description
borderStyle	"single" | "double" | "round" | "bold" | "singleDouble" | "doubleSingle" | "classic"	-	Border style
borderColor	string	-	Border color
borderTop	boolean	true	Show top border
borderBottom	boolean	true	Show bottom border
borderLeft	boolean	true	Show left border
borderRight	boolean	true	Show right border

Style (Colors and Text Formatting)

Prop	Type	Default	Description
backgroundColor	string	-	Fill the entire box area with a background color
color	string	-	Text color for child content
bold	boolean	false	Bold text
dim	boolean	false	Dimmed (faint) text
dimColor	boolean	false	Alias for dim (Ink compatibility)
italic	boolean	false	Italic text
underline	boolean	false	Underlined text
strikethrough	boolean	false	Strikethrough text
inverse	boolean	false	Swap foreground/background colors

Box vs Text backgroundColor

Unlike Ink, Silvery's Box supports backgroundColor directly. The background fills the entire computed layout area, so you don't need Text elements with spaces to create filled regions.

Overflow (Silvery Only)

Prop	Type	Default	Description
overflow	"visible" | "hidden" | "scroll"	"visible"	Overflow behavior
scrollTo	number	-	Child index to keep visible (for overflow="scroll")

Callbacks

Prop	Type	Default	Description
onLayout	(layout: ComputedLayout) => void	-	Called when layout is computed

The ComputedLayout type:

interface ComputedLayout {
  x: number // X position relative to root
  y: number // Y position relative to root
  width: number // Computed width in columns
  height: number // Computed height in rows
}

Border Styles Reference

Style	Example	Characters Used
single	┌─┐ │ │ └─┘	Light box-drawing characters
double	╔═╗ ║ ║ ╚═╝	Double-line box-drawing
round	╭─╮ │ │ ╰─╯	Rounded corners, single lines
bold	┏━┓ ┃ ┃ ┗━┛	Heavy/bold box-drawing
singleDouble	╓─╖ ║ ║ ╙─╜	Single horizontal, double vertical
doubleSingle	╒═╕ │ │ ╘═╛	Double horizontal, single vertical
classic	+-+ | | +-+	ASCII characters only

Examples

Row Layout

<Box flexDirection="row" gap={2}>
  <Text>Left</Text>
  <Text>Middle</Text>
  <Text>Right</Text>
</Box>

Output:

Left  Middle  Right

Column Layout

<Box flexDirection="column">
  <Text>Line 1</Text>
  <Text>Line 2</Text>
  <Text>Line 3</Text>
</Box>

Output:

Line 1
Line 2
Line 3

Equal Width Columns

<Box flexDirection="row">
  <Box flexGrow={1} borderStyle="single">
    <Text>Column 1</Text>
  </Box>
  <Box flexGrow={1} borderStyle="single">
    <Text>Column 2</Text>
  </Box>
  <Box flexGrow={1} borderStyle="single">
    <Text>Column 3</Text>
  </Box>
</Box>

Centered Content

<Box justifyContent="center" alignItems="center" height={10}>
  <Text>Centered!</Text>
</Box>

Fixed and Flexible Layout

Use flexShrink={0} for fixed elements and flexGrow={1} for flexible areas:

<Box flexDirection="column" height="100%">
  {/* Fixed header - won't shrink */}
  <Box height={1} flexShrink={0} backgroundColor="blue">
    <Text color="white" bold>
      Header
    </Text>
  </Box>

  {/* Flexible content - fills remaining space */}
  <Box flexGrow={1}>
    <Text>Content area</Text>
  </Box>

  {/* Fixed footer - won't shrink */}
  <Box height={1} flexShrink={0}>
    <Text dimColor>Footer</Text>
  </Box>
</Box>

Scrollable List

const [selected, setSelected] = useState(0)

<Box flexDirection="column" height={5} overflow="scroll" scrollTo={selected}>
  {items.map((item, i) => (
    <Text key={i} inverse={i === selected}>
      {item}
    </Text>
  ))}
</Box>

Sticky Header in Scrollable Container

<Box flexDirection="column" height={10} overflow="scroll" scrollTo={selected}>
  {/* This header stays visible when scrolling */}
  <Box position="sticky" stickyTop={0} backgroundColor="blue">
    <Text color="white" bold>
      Pinned Header
    </Text>
  </Box>

  {items.map((item, i) => (
    <Text key={i} inverse={i === selected}>
      {item}
    </Text>
  ))}
</Box>

Absolute Positioning

<Box position="relative" width={40} height={10}>
  <Text>Background content</Text>

  {/* Positioned absolutely within the parent */}
  <Box position="absolute">
    <Text color="red">Overlay</Text>
  </Box>
</Box>

Border Styles

// Single line border
<Box borderStyle="single">
  <Text>Content</Text>
</Box>

// Rounded corners
<Box borderStyle="round">
  <Text>Content</Text>
</Box>

// Double line border
<Box borderStyle="double">
  <Text>Content</Text>
</Box>

// Colored border
<Box borderStyle="single" borderColor="green">
  <Text>Content</Text>
</Box>

// Partial borders
<Box borderStyle="single" borderTop borderBottom borderLeft={false} borderRight={false}>
  <Text>Top and bottom only</Text>
</Box>

Filled Background

// Header bar with cyan background
<Box backgroundColor="cyan" paddingX={1}>
  <Text color="black" bold>
    Title
  </Text>
</Box>

// Sidebar indicator that fills available height
<Box
  width={1}
  flexGrow={1}
  backgroundColor="gray"
  justifyContent="center"
  alignItems="center"
>
  <Text color="white">›</Text>
</Box>

Using onLayout

function MeasuredBox() {
  const [size, setSize] = useState({ width: 0, height: 0 })

  return (
    <Box
      flexGrow={1}
      onLayout={(layout) => setSize({ width: layout.width, height: layout.height })}
    >
      <Text>
        Size: {size.width}x{size.height}
      </Text>
    </Box>
  )
}

Conditional Display

<Box flexDirection="column">
  <Text>Always visible</Text>
  <Box display={showDetails ? "flex" : "none"}>
    <Text>Conditionally shown</Text>
  </Box>
</Box>

Space Distribution

// Evenly distributed items
<Box flexDirection="row" justifyContent="space-between" width={40}>
  <Text>Left</Text>
  <Text>Center</Text>
  <Text>Right</Text>
</Box>

// Equal spacing around items
<Box flexDirection="row" justifyContent="space-around" width={40}>
  <Text>A</Text>
  <Text>B</Text>
  <Text>C</Text>
</Box>

// Equal spacing between items (including edges)
<Box flexDirection="row" justifyContent="space-evenly" width={40}>
  <Text>A</Text>
  <Text>B</Text>
  <Text>C</Text>
</Box>

Percentage Sizing

<Box flexDirection="row" width="100%">
  {/* Takes 30% of parent width */}
  <Box width="30%" backgroundColor="blue">
    <Text>Sidebar</Text>
  </Box>

  {/* Takes 70% of parent width */}
  <Box width="70%" backgroundColor="gray">
    <Text>Main content</Text>
  </Box>
</Box>