Struct DragTrack 

pub struct DragTrack {
    pub inset: f32,
    pub mirrored: bool,
    pub mode: DragMode,
}

Where a drag lands along a widget that takes one: see Widget::drag_track.

Fields

inset: f32

How far in from each end the travel starts, in logical pixels.

mirrored: bool

Whether the travel runs from the right in a right-to-left reading direction.

mode: DragMode

How a press and a slide move the value (milestone 650).

Implementations

impl DragTrack

pub const WHOLE: Self

The whole width, left to right, following the pointer: what a widget with no opinion answers.

pub fn fraction(self, rect: Rect, x: f32, rtl: bool) -> f32

Where x falls along rect’s travel, as a fraction 0..=1, for a reading direction that is right to left when rtl.

One function, used by a drag’s start, every move and its end alike: three copies of this arithmetic would agree on every slider until one of them did not.

pub fn engages(self, rect: Rect, x: f32, rtl: bool) -> bool

Whether a press at x starts anything at all: always, but for DragMode::SlideThumb, which wants the press on its thumb.

pub fn value_at( self, rect: Rect, press_x: f32, x: f32, moved: bool, rtl: bool, ) -> Option<f32>

The value a drag pressed at press_x and now at x stands for, as a fraction of the travel; None when this moment changes nothing. moved is false for the press itself and true for every movement after it — and for the release, which is where the slide ended.

A slide that started from the value moves it by the pointer’s movement, as the reference’s does, so a thumb grabbed off its centre does not jump to the pointer.

pub fn pick_thumb( self, rect: Rect, press_x: f32, dx: f32, rtl: bool, ) -> Option<usize>

Which thumb a press at press_x takes on a DragMode::Thumbs track, 0 for the start and 1 for the end, the movement since the press being dx — the reference’s _defaultRangeThumbSelector. The nearer thumb, unless the press is on both, when the first movement decides: towards the start takes the start. None while that is undecided, or on a track without thumbs.

pub fn released_at(self, rect: Rect, press_x: f32, x: f32, rtl: bool) -> f32

The value a drag pressed at press_x lets go of at x: where the pointer is, where the press set it, or where the slide took it.

Trait Implementations

impl Clone for DragTrack

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for DragTrack

impl Debug for DragTrack

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

Formats the value using the given formatter.

impl PartialEq for DragTrack

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for DragTrack