Module nav_row 

One navigation row and one navigation section header, painted the same everywhere.

NavList paints every row through paint_nav_row and every section header through paint_nav_section; a painted app that cannot host a NavList calls the same two functions with the same faces, so a sidebar drawn by hand is pixel-for-pixel the widget’s. The geometry (nav_row_layout, nav_section_layout) is public so a painted host hit-tests exactly what was painted.

A row is the list’s s2 inset from both edges; its selection is the neutral lift of the ground it stands on (super::paint_row_selection), with primary ink. Counts are Caption tabular figures in tertiary ink; a NavCount::Live count (unread, needs attention) is the one filled badge, in the person’s own colour. Section headers are sentence-case Subheading in secondary ink.

Every part a row can show, leading to trailing:

Part	Face	Look
check	NavRowFace::checked	a crate::widget::CheckboxFace; the whole row toggles it
icon, swatch or avatar	NavRowFace::icon, NavRowFace::swatch, NavRowFace::avatar	a ui::icons glyph, the content colour the row stands for, or the person it stands for
badge	NavRowFace::badge	a short classifying code on a quiet pill, in a column shared by its section
label	NavRowFace::new	Body; Body.strong() while selected
secondary	NavRowFace::secondary	one Caption line under the label, in secondary ink
level	NavRowFace::level	a usage bar under the text, on the progress bar’s track and fill
presence	NavRowFace::presence	the people on it, as marks in their colour
status label	NavRowFace::status_label	a quiet tinted badge (“Active”)
meta	NavRowFace::meta	a tertiary Caption figure (a size)
count	NavRowFace::count	quiet tabular figures, or the live badge
status	NavRowFace::status	a dot at the trailing edge

Hover and focus swap the trailing parts for the row’s actions.

Draw with the theme of the ground the rows stand on (theme.in_region(Region::Sidebar) in a sidebar, theme.on_ground(..) elsewhere): the painter reads that ground from surfaces.content.

Structs

NavRowFace

Everything a navigation row shows. Build with NavRowFace::new and paint with paint_nav_row.

NavRowLayout

Where each part of a navigation row lands. Painting and hit-testing both read it.

NavSectionFace

A section header in a navigation list.

NavSectionLayout

Where each part of a section header lands.

Enums

NavCount

How many items a navigation row stands for, beside its label.

NavRowStyle

A row laid out as a list row or as a tile in an icon-over-label rail.

Functions

label_measure_style

The heavier of a row’s two weights: elision is measured with it, so a label that fits selected also fits unselected.

label_style

The style a row’s label is set in: Body, or Body.strong() while the row is selected. Measure elision with label_measure_style so the label does not jump when the weight changes.

nav_badge_column

The width of the badge column a section’s rows share: the widest of codes on its pill.

nav_item_height

Height of a list row that carries a secondary line and/or a usage bar under its label: the stacked text inside the row’s s2 padding, never shorter than nav_row_height.

nav_list_width_fitting

How wide an icon-led list of these destination labels must be for every label to stand whole beside its icon: the row’s padding, its icon and gap, and the widest label. Where a sidebar is narrower than this, its destinations read better as a rail’s tiles than as cut-off rows, so this is where a navigation sidebar turns from rail into list.

nav_rail_item_height

Height of the rail tile for label in a rail width wide: one caption line more than nav_rail_row_height when the caption wraps.

nav_rail_row_height

Height of one rail tile: the icon over a caption line inside the row padding.

nav_row_description

The spoken form of a row’s extra parts, for its accessible description: the secondary line, the meta, the state.

nav_row_height

Height of one list row: crate::tokens::Metrics::nav_row_height, grown with the body line at large text.

nav_row_layout

Lay out face inside its row (see NavRowLayout).

nav_section_height

Height of a section header. Every section after the first is separated from the rows above it by s3 of space, not by a line.

nav_section_layout

Lay out a section header (see NavSectionLayout).

paint_nav_row

Paint one navigation row. theme is the theme of the ground the row stands on; its surfaces.content is that ground.

paint_nav_section

Paint a section header: the title in Subheading, secondary ink; a collapsible section’s chevron while the pointer or focus is on it (or while it is collapsed, so a hidden section is never mistaken for an empty one); and its trailing action.

rail_caption_fits

Whether label stands whole in a rail tile width wide: on at most two caption lines, broken only at spaces, with nothing elided.

rail_caption_lines

A rail caption broken into at most two lines of max_w, only at spaces: a single word never breaks inside, it elides when it is longer than the line, and so does the second line.

rail_width_fitting

How wide a rail of these destination labels is: its stock width, grown with the text so its longest single word fits whole, but never past the stock width times the text’s growth nor metrics.rail_max_width. A fragment such as “Cha…” names nothing, so the rail widens before any word is shortened; only past that cap does a word elide.

sidebar_rail_width_fitting

How wide a sidebar’s rail of these destination labels is: its stock width, grown so its longest single word fits whole, up to metrics.rail_max_width. A sidebar the person can widen into a list grows its rail to the word before it shortens one (“Subscriptions”, never “Subscript…”); a fixed rail keeps rail_width_fitting’s cap.