Struct nannou::ui::widget::scroll::State [−][src]
pub struct State<A> { pub offset: f64, pub offset_bounds: Range, pub scrollable_range_len: f64, pub is_scrolling: bool, // some fields omitted }
Expand description
Scroll state calculated for a single axis.
Fields
offset: f64
The distance that has been scrolled from the origin.
A positive offset pushes the scrollable range that is under the kid_area upwards.
A negative offset pushes the scrollable range that is under the kid_area downwards.
offset_bounds: Range
The start and end bounds for the offset along the axis.
scrollable_range_len: f64
The total range which may be “offset” from the “root” range (aka the kid_area
).
The scrollable_range
is determined as the bounding range around both the kid_area
and
all un-scrolled visible children widgets.
is_scrolling: bool
Whether or not the this axis is currently scrolling.
Implementations
Calculate the new scroll state for the single axis of a Widget
.
> +---+
| | |
| =========================
| | | a | scroll root |
| | +---+ aka `kid_area` |
| | +--------+ |
| | | | |
| =========================
| | b |
| +--------+
scrollable| +--------+
range y| | |
| | | +------+
| | c | | |
| +--------+ | d |
| | |
> +------+
^--------------------^
scrollable
range x
kid_area
is the cropped area of the container widget in which kid widgets may be viewed.a
,b
,c
andd
are widgets that are kids of the “scroll root” widget in their original, un-scrolled positions.scrollable_range
is the total range occuppied by all children widgets in their original, un-scrolled positions.
Everything above and below the set of ==== bars of the parent widget is hidden, i.e:
=========================
| | a | scroll root |
| +---+ aka `kid_area` |
| +--------+ |
| | b | |
=========================
The scrollable_range
on each axis only becomes scrollable if its length exceeds the
length of the kid_area
on the same axis. Thus, in the above example, only the y
scrollable_range is scrollable.
The offset_bounds
are calculated as the amount which the original, un-scrolled,
scrollable_range
may be offset from its origin.
offset + >
bounds v |
.start > | =========================
| | |
| | kid_area |
| | |
| | |
> scrollable | =========================
^ range y |
^ |
^ |
offset ^ |
bounds ^ |
.end ^ |
^ |
^ |
+ >
Trait Implementations
Auto Trait Implementations
impl<A> RefUnwindSafe for State<A> where
A: RefUnwindSafe,
impl<A> UnwindSafe for State<A> where
A: UnwindSafe,
Blanket Implementations
impl<S, D, Swp, Dwp, T> AdaptInto<D, Swp, Dwp, T> for S where
T: Component + Float,
D: AdaptFrom<S, Swp, Dwp, T>,
Swp: WhitePoint,
Dwp: WhitePoint,
impl<S, D, Swp, Dwp, T> AdaptInto<D, Swp, Dwp, T> for S where
T: Component + Float,
D: AdaptFrom<S, Swp, Dwp, T>,
Swp: WhitePoint,
Dwp: WhitePoint,
Mutably borrows from an owned value. Read more
Convert into T with values clamped to the color defined bounds Read more
Convert into T. The resulting color might be invalid in its color space Read more
Convert into T, returning ok if the color is inside of its defined range,
otherwise an OutOfBounds
error is returned which contains the unclamped color. Read more
pub fn vzip(self) -> V