Enum Breakpoint 

pub enum Breakpoint {
    Compact,
    Medium,
    Wide,
}

The one size class a surface derives from the rect it is laid out in.

A window’s shape is a fact about its current allocation, never a decision an app (or the host that launched it) stores: every layout pass asks this of the rect it was just handed, so a window narrowed or widened shows the layout that rect asks for on the very next frame.

• Compact — one column at a time: phone width, a tablet held upright, a window dragged narrow. The sidebar, list and content are screens the person moves between.
• Medium — a docked sidebar and one primary column beside it: a small laptop, a large tablet on its side.
• Wide — a sidebar, a primary column and a second column (an overview beside a detail, a document beside an inspector).

The thresholds come from Metrics, so they grow with ui_scale and the text scale exactly as the panels they separate do. A surface that holds a class across frames uses BreakpointTracker, which keeps a threshold from flapping when a window is dragged across it.

Variants

Compact

One column at a time.

Medium

A docked sidebar and a primary column.

Wide

A sidebar, a primary column and a column beside it.

Implementations

impl Breakpoint

pub fn thresholds(m: &Metrics) -> (f64, f64)

The widths this class asks for, from the tokens: (compact, wide) — below the first a surface shows one column at a time, at or above the second it shows a column beside the primary one. Between them it docks its sidebar and keeps one column.

The compact threshold is the sidebar beside the content it has to keep (Metrics::compact_breakpoint); a second column joins at the overview’s width past it, which is where a list beside a detail fits beside a docked sidebar.

pub fn of(width: f64, m: &Metrics) -> Breakpoint

The class width asks for, without hysteresis: the answer a fresh rect gets. A surface that lays out repeatedly asks BreakpointTracker::derive instead.

width is in the space m is measured in. A surface whose text has grown divides its rect’s width by Metrics::text_growth first, so a window at 200 % text reaches each class where a 1× window half its width does — the rule every text-sized breakpoint in the toolkit already follows.

pub fn is_compact(self) -> bool

Whether the surface shows one column at a time.

pub fn is_wide(self) -> bool

Whether the surface has room for a column beside its primary one.

Trait Implementations

impl Clone for Breakpoint

fn clone(&self) -> Breakpoint

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Breakpoint

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for Breakpoint

fn default() -> Breakpoint

Returns the “default value” for a type.

impl Hash for Breakpoint

fn hash<__H>(&self, state: &mut __H)

where __H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Breakpoint

fn cmp(&self, other: &Breakpoint) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Breakpoint

fn eq(&self, other: &Breakpoint) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for Breakpoint

fn partial_cmp(&self, other: &Breakpoint) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Copy for Breakpoint

impl Eq for Breakpoint

impl StructuralPartialEq for Breakpoint