View and layout reference

This page is the task-oriented index to the View API. Use the generated Rust API reference for every signature, generic bound, trait implementation, and source link:

Complete urushi API
View, BlockTitle, and GridStyle
BlockStyle, Border, Length, and Overflow
Viewport, Key, and ResolvedView
Available, LayoutError, and LayoutErrorKind

Block geometry

BlockStyle::new() starts empty. from_text_style installs one complete text style for block-created cells; text_style() returns it.

Color, attributes, underline, hyperlink, and their resets/getters are indexed under BlockStyle cell appearance. They style cells created by the block and do not cascade into its child.

Area	Builders
Spacing	`padding`, `margin` and their resets
Border	`border`, four edge toggles, border text style/foreground/background, and resets
Size	`width`, `height`, min/max width/height, and resets
Content	`overflow`, `align`, `vertical_align`, and resets

Every field has a corresponding get_* accessor. frame_size() returns the fixed margin, enabled border, and padding contribution, excluding content and content-dependent dimensions.

Built-in Border repertoires are NORMAL, ROUNDED, THICK, DOUBLE, ASCII, and HIDDEN. Its fields are public for custom repertoires.

Dimensions and alignment

Length::Cells(u16) is fixed.
Length::Fill(non-zero weight) divides remaining parent space.
Length::fill panics on zero; try_fill returns InvalidFillWeight.
Align is Left, Center, or Right.
VerticalAlign is Top, Center, or Bottom.
Sides stores top, right, bottom, and left spacing and accepts the supported scalar and tuple conversions.

Overflow is Wrap (the default) or Clip(marker). Constructors clip, ellipsis, and clip_with select clipping markers; clip_marker() returns the optional marker.

Grid layout

GridStyle::new() uses content-sized columns and no cell padding. columns sets optional Length values by position; cell_padding sets default cell padding. Reset and getter methods are available for both settings.

View constructors

Constructor	Result
`View::text(text, style)`	Plain text flow with one complete `TextStyle`
`View::styled_text(text)`	One `StyledText` flow with multiple spans
`View::block(style, child)`	One child in a box model
`View::titled_block(style, title, child)`	Block with a one-line top-border title
`View::row(align, children)`	Horizontal children with vertical cross-axis alignment
`View::column(align, children)`	Vertical children with horizontal cross-axis alignment
`View::grid(style, rows)`	Rectangular grid with shared column widths
`View::canvas(canvas)`	Finite free-positioned surface
`View::viewport(viewport, child)`	Finite projection of one child
`View::anchor_block(key, style, child)`	Block that reports its content rectangle
`View::titled_anchor_block(key, style, title, child)`	Titled block that reports its content rectangle
`View::anchor(key)`	Zero-size reported origin
`View::empty()`	Empty rectangle

View::default() is View::empty().

Text accepts newlines and tabs but not terminal controls or raw ANSI. Every grid row must have the same number of cells. A titled block requires an enabled top border.

Resolution

API	Purpose
`measure(view)`	Intrinsic `Size`; panics on layout error
`try_measure(view)`	Intrinsic `Size` or `LayoutError`
`resolve(view, available)`	One `ResolvedView` under an available area
`Resolver::new()`	Reusable resolver with a layout cache
`Resolver::resolve(view, available)`	Resolve through that cache
`Resolver::clear()`	Clear reusable state

Use the two-frame Resolver guide for the stateless-versus-retained choice, viewport reprojection, invalidation, clear, and host-state ownership.

`Available`

Value	Meaning
`Available::NONE`	Both axes unbounded
`Available::new(width, height)`	Optional bound per axis
`Available::columns(width)`	Width bounded, height unbounded
`Available::size(width, height)`	Both axes bounded

width() and height() return the optional bounds.

`ResolvedView`

API	Meaning
`size()`	Settled cell rectangle
`rows()`	Rows of `StyledGrapheme` values
`anchors()`	Every reported `AnchoredRect`
`anchor(key)`	One anchor by opaque key

StyledGrapheme exposes symbol, width, and style.

Projection

Projection::new(origin, boundary) stores a signed origin and either ProjectionBoundary::Preserve or Clamp. Accessors are origin() and boundary().

Viewport::horizontal, vertical, and both select projected axes. horizontal_projection() and vertical_projection() return their optional definitions. Construction always selects at least one axis.

Block titles

BlockTitle::new(text) creates a left-aligned, one-line title with one preferred blank cell on each side. Builders are align and padding; accessors are text, alignment, and horizontal_padding. &str, String, and StyledText convert into a title.

Anchored geometry

AnchoredRect exposes its key, signed x and y, width, height, is_empty, is_within_resolved_view, and optional clipped visible rectangle. VisibleRect exposes signed position and finite dimensions.

Layout errors

LayoutError::axis() identifies the failing Axis; kind() identifies the LayoutErrorKind. Missing Canvas extents and missing allocations for Views placed in Canvas are reported rather than silently choosing a size.