Struct Scroll 

pub struct Scroll { /* private fields */ }

A scroll view

Implementations

impl Scroll

pub fn new(child: impl IntoView) -> Self

Creates a new scroll view wrapping the given child view.

Example

use floem::views::*;

let content = Label::new("Scrollable content");
let scrollable = Scroll::new(content);

pub fn on_scroll(self, onscroll: impl Fn(Rect) + 'static) -> Self

Sets a callback that will be triggered whenever the scroll position changes.

This callback receives the viewport rectangle that represents the currently visible portion of the scrollable content.

pub fn on_child_size(self, callback: impl Fn(Size) + 'static) -> Self

Sets a callback that will be triggered whenever the child’s size changes after layout.

This is useful for reactive code that needs to depend on the actual laid-out size of the scroll content, ensuring proper ordering when combined with ensure_visible.

pub fn ensure_visible(self, to: impl Fn() -> Rect + 'static) -> Self

Ensures that a specific rectangular area is visible within the scroll view by automatically scrolling to it if necessary.

Reactivity

The viewport will automatically update to include the target rectangle whenever the rectangle’s position or size changes, as determined by the to function which will update any time there are changes in the signals that it depends on.

pub fn scroll_delta(self, delta: impl Fn() -> Vec2 + 'static) -> Self

Scrolls the view by the specified delta vector.

Reactivity

The scroll position will automatically update whenever the delta vector changes, as determined by the delta function which will update any time there are changes in the signals that it depends on.

pub fn scroll_to(self, origin: impl Fn() -> Option<Point> + 'static) -> Self

Scrolls the view to the specified target point.

Reactivity

The scroll position will automatically update whenever the target point changes, as determined by the origin function which will update any time there are changes in the signals that it depends on.

pub fn scroll_to_percent(self, percent: impl Fn() -> f32 + 'static) -> Self

Scrolls the view to the specified percentage (0-100) of its scrollable content.

Reactivity

The scroll position will automatically update whenever the target percentage changes, as determined by the percent function which will update any time there are changes in the signals that it depends on.

pub fn scroll_to_view(self, view: impl Fn() -> Option<ViewId> + 'static) -> Self

Scrolls the view to make a specific view visible.

Reactivity

The scroll position will automatically update whenever the target view changes, as determined by the view function which will update any time there are changes in the signals that it depends on.

pub fn ensure_area_visible( &mut self, window_state: &mut WindowState, rect: Rect, )

Ensure that an entire area is visible in the scroll view.

pub fn pan_to_visible(&mut self, window_state: &mut WindowState, rect: Rect)

Pan the smallest distance that makes the target Rect visible.

If the target rect is larger than viewport size, we will prioritize the region of the target closest to its origin.

pub fn scroll_style( self, style: impl Fn(ScrollCustomStyle) -> ScrollCustomStyle + 'static, ) -> Self

Sets the custom style properties of the Scroll.

Trait Implementations

impl CustomStylable<ScrollCustomStyle> for Scroll

type DV = Scroll

The view type that this custom stylable converts to.

fn custom_style(self, style: impl Fn(S) -> S + 'static) -> Self::DV

Applies custom styling to the view with access to specialized custom style methods.

impl View for Scroll

fn id(&self) -> ViewId

fn debug_name(&self) -> Cow<'static, str>

fn view_style(&self) -> Option<Style>

fn update(&mut self, cx: &mut UpdateCx<'_>, state: Box<dyn Any>)

Use this method to react to changes in view-related state. You will usually send state to this hook manually using the View’s Id handle

fn scroll_to( &mut self, cx: &mut WindowState, target: ViewId, rect: Option<Rect>, ) -> bool

Scrolls the view and all direct and indirect children to bring the target view to be visible. Returns true if this view contains or is the target.

fn style_pass(&mut self, cx: &mut StyleCx<'_>)

Use this method to style the view’s children.

fn compute_layout(&mut self, cx: &mut ComputeLayoutCx<'_>) -> Option<Rect>

Responsible for computing the layout of the view’s children.

fn event_before_children( &mut self, cx: &mut EventCx<'_>, event: &Event, ) -> EventPropagation

fn event_after_children( &mut self, cx: &mut EventCx<'_>, event: &Event, ) -> EventPropagation

fn paint(&mut self, cx: &mut PaintCx<'_>)

View-specific implementation. Will be called in PaintCx::paint_view. Usually you’ll call paint_view for every child view. But you might also draw text, adjust the offset, clip or draw text.

fn view_class(&self) -> Option<StyleClassRef>

fn layout(&mut self, cx: &mut LayoutCx<'_>) -> NodeId

Use this method to layout the view’s children. Usually you’ll do this by calling LayoutCx::layout_node.