Struct Scrollable 

pub struct Scrollable<'a, Message, W = Element<'a, Message>, Theme = Theme>
where
    Theme: Catalog,
{ /* private fields */ }

A widget that can vertically display an infinite amount of content with a scrollbar.

Example

use iced::widget::{column, scrollable, space};

enum Message {
    // ...
}

fn view(state: &State) -> impl Widget<Message> {
    scrollable(column![
        "Scroll me!",
        space().height(3000),
        "You did it!",
    ])
}

Scrollbars

A scrollbar has two interactive parts: the scroller (the draggable thumb) and the rail (the track it slides on).

• Pressing and dragging the scroller moves it 1:1 with the pointer.
• Pressing the rail scrolls one page (animated like a wheel scroll when Self::smooth_scroll is enabled). While the button is held, the scroller then slides toward the pointer at a constant speed, stopping when its edge reaches the pointer; moving the pointer moves the target with it. This mirrors the track autoscroll of most toolkits.
• Shift-clicking the rail instead jumps the scroller so that its center is under the pointer, and then drags it from there.

With Self::click_to_scroll enabled, the behavior of the rail press and the Shift-click is inverted.

Implementations

impl<'a, Message, W, Theme> Scrollable<'a, Message, W, Theme>

where Theme: Catalog,

pub fn new(content: W) -> Self

Creates a new vertical Scrollable.

pub fn with_direction(content: W, direction: impl Into<Direction>) -> Self

Creates a new Scrollable with the given Direction.

pub fn horizontal(self) -> Self

Makes the Scrollable scroll horizontally, with default Scrollbar settings.

pub fn direction(self, direction: impl Into<Direction>) -> Self

Sets the Direction of the Scrollable.

pub fn id(self, id: impl Into<Id>) -> Self

Sets the widget::Id of the Scrollable.

pub fn width(self, width: impl Into<Length>) -> Self

Sets the width of the Scrollable.

pub fn height(self, height: impl Into<Length>) -> Self

Sets the height of the Scrollable.

pub fn on_scroll<T>(self, f: impl Fn(Scroll) -> T + 'a) -> Self

where T: Into<Action<Message>>,

Sets a handler to call when the Scrollable is scrolled.

The function takes a Scroll, which contains the Viewport of the Scrollable and the Source of the scroll that caused the notification.

pub fn anchor_top(self) -> Self

Anchors the vertical Scrollable direction to the top.

pub fn anchor_bottom(self) -> Self

Anchors the vertical Scrollable direction to the bottom.

pub fn anchor_left(self) -> Self

Anchors the horizontal Scrollable direction to the left.

pub fn anchor_right(self) -> Self

Anchors the horizontal Scrollable direction to the right.

pub fn anchor_x(self, alignment: Anchor) -> Self

Sets the Anchor of the horizontal direction of the Scrollable, if applicable.

pub fn anchor_y(self, alignment: Anchor) -> Self

Sets the Anchor of the vertical direction of the Scrollable, if applicable.

pub fn spacing(self, new_spacing: impl Into<Pixels>) -> Self

Embeds the Scrollbar into the Scrollable, instead of floating on top of the content.

The spacing provided will be used as space between the Scrollbar and the contents of the Scrollable.

pub fn padding(self, new_padding: impl Into<Pixels>) -> Self

Adds padding at the ends of the Scrollbars of the Scrollable.

The padding provided will be used as space at the top and bottom of a vertical Scrollbar, and at the left and right ends of a horizontal Scrollbar, when they are visible.

Unlike Self::spacing, the padding does not affect the layout of the Scrollable.

pub fn auto_scroll(self, auto_scroll: bool) -> Self

Sets whether the user should be allowed to auto-scroll the Scrollable with the middle mouse button.

By default, it is disabled.

pub fn smooth_scroll(self, smooth_scroll: bool) -> Self

Sets whether wheel scrolling should be smoothed out over time, instead of moving the Scrollable immediately.

When enabled, discrete scrolls (e.g. from a mouse wheel) move a target scroll offset — carrying the momentum of the wheel notches — and the Scrollable eases towards it over a few frames. High-precision scrolls (e.g. from a touchpad), which are already smooth, are always applied immediately.

The setting also acts as the default behavior of the scroll operations (snap_to, scroll_to, scroll_by): operations with [Animation::Auto] scroll smoothly if and only if it is enabled.

By default, it is enabled.

pub fn click_to_scroll(self, click_to_scroll: bool) -> Self

Sets whether a plain click on the scrollbar rail should jump the scroller to the click position, instead of scrolling one page.

By default, a press on the rail scrolls one page (and autoscrolls while the button is held), while a Shift-click jumps the scroller so that its center is under the pointer and drags it from there.

When enabled, the behavior is inverted: a plain click jumps the scroller so that its center is under the pointer (and drags it from there), while a Shift-click scrolls one page (and autoscrolls while the button is held).

By default, it is disabled.

pub fn style(self, style: impl Fn(&Theme, Status) -> Style + 'a) -> Self

where Theme::Class<'a>: From<StyleFn<'a, Theme>>,

Sets the style of this Scrollable.

pub fn class(self, class: impl Into<Theme::Class<'a>>) -> Self

Available on crate feature advanced only.

Sets the style class of the Scrollable.

Trait Implementations

impl<Message, W, Theme> Meta for Scrollable<'_, Message, W, Theme>

where Theme: Catalog,

fn is_void(&self) -> bool

Returns whether the [Widget] is Void.

impl<Message, W, Theme, Renderer> Widget<Message, Theme, Renderer> for Scrollable<'_, Message, W, Theme>

where Theme: Catalog, Renderer: Renderer, W: Widget<Message, Theme, Renderer>,

fn tag(&self) -> Tag

Returns the Tag of the [Widget].

fn state(&self) -> State

Returns the State of the [Widget].

fn diff(&mut self, tree: &mut Tree)

Reconciles the [Widget] with the provided [Tree].

fn size(&self) -> Size<Length>

Returns the [Size] of the [Widget] in lengths.

fn layout(&mut self, tree: &mut Tree, renderer: &Renderer, limits: &Limits)

Lays out the [Widget].

fn operate( &mut self, tree: &mut Tree, layout: Layout, viewport: &Rectangle, renderer: &Renderer, operation: &mut dyn Operation, )

Applies an [Operation] to the [Widget].

fn update( &mut self, tree: &mut Tree, event: &Event, layout: Layout, cursor: Cursor, renderer: &Renderer, shell: &mut Shell<'_, Message>, viewport: &Rectangle, )

Processes a runtime Event.

fn draw( &self, tree: &Tree, renderer: &mut Renderer, theme: &Theme, defaults: &Style, layout: Layout, cursor: Cursor, viewport: &Rectangle, )

Draws the [Widget] using the associated Renderer.

fn mouse_interaction( &self, tree: &Tree, layout: Layout, cursor: Cursor, viewport: &Rectangle, renderer: &Renderer, ) -> Interaction

Returns the current [mouse::Interaction] of the [Widget].

fn overlay<'b>( &'b mut self, tree: &'b mut Tree, layout: Layout, renderer: &Renderer, viewport: &Rectangle, translation: Vector, window: Size, ) -> Vec<Element<'b, Message, Theme, Renderer>>

Returns the overlays of the [Widget].

fn _map<F, B>(self, f: F) -> Map<Self, F, Message>

where Self: Sized, F: Fn(Message) -> B,

Applies a transformation to the produced message of this [Widget], returning a [Map].

fn _boxed<'a>(self) -> Element<'a, Message, Theme, Renderer>

where Self: Sized + 'a,

Boxes this [Widget], turning it into a generic [Element].