2083 lines
67 KiB
Rust
2083 lines
67 KiB
Rust
//! Scrollables let users navigate an endless amount of content with a scrollbar.
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//!
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//! # Example
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//! ```no_run
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//! # mod iced { pub mod widget { pub use iced_widget::*; } }
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//! # pub type State = ();
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//! # pub type Element<'a, Message> = iced_widget::core::Element<'a, Message, iced_widget::Theme, iced_widget::Renderer>;
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//! use iced::widget::{column, scrollable, vertical_space};
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//!
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//! enum Message {
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//! // ...
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//! }
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//!
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//! fn view(state: &State) -> Element<'_, Message> {
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//! scrollable(column![
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//! "Scroll me!",
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//! vertical_space().height(3000),
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//! "You did it!",
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//! ]).into()
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//! }
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//! ```
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use crate::container;
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use crate::core::border::{self, Border};
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use crate::core::keyboard;
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use crate::core::layout;
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use crate::core::mouse;
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use crate::core::overlay;
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use crate::core::renderer;
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use crate::core::time::{Duration, Instant};
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use crate::core::touch;
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use crate::core::widget;
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use crate::core::widget::operation::{self, Operation};
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use crate::core::widget::tree::{self, Tree};
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use crate::core::window;
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use crate::core::{
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self, Background, Clipboard, Color, Element, Event, InputMethod, Layout,
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Length, Padding, Pixels, Point, Rectangle, Shell, Size, Theme, Vector,
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Widget,
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};
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use crate::runtime::Action;
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use crate::runtime::task::{self, Task};
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pub use operation::scrollable::{AbsoluteOffset, RelativeOffset};
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/// A widget that can vertically display an infinite amount of content with a
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/// scrollbar.
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///
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/// # Example
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/// ```no_run
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/// # mod iced { pub mod widget { pub use iced_widget::*; } }
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/// # pub type State = ();
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/// # pub type Element<'a, Message> = iced_widget::core::Element<'a, Message, iced_widget::Theme, iced_widget::Renderer>;
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/// use iced::widget::{column, scrollable, vertical_space};
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///
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/// enum Message {
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/// // ...
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/// }
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///
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/// fn view(state: &State) -> Element<'_, Message> {
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/// scrollable(column![
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/// "Scroll me!",
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/// vertical_space().height(3000),
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/// "You did it!",
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/// ]).into()
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/// }
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/// ```
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#[allow(missing_debug_implementations)]
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pub struct Scrollable<
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'a,
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Message,
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Theme = crate::Theme,
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Renderer = crate::Renderer,
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> where
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Theme: Catalog,
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Renderer: core::Renderer,
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{
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id: Option<Id>,
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width: Length,
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height: Length,
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direction: Direction,
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content: Element<'a, Message, Theme, Renderer>,
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on_scroll: Option<Box<dyn Fn(Viewport) -> Message + 'a>>,
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class: Theme::Class<'a>,
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last_status: Option<Status>,
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}
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impl<'a, Message, Theme, Renderer> Scrollable<'a, Message, Theme, Renderer>
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where
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Theme: Catalog,
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Renderer: core::Renderer,
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{
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/// Creates a new vertical [`Scrollable`].
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pub fn new(
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content: impl Into<Element<'a, Message, Theme, Renderer>>,
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) -> Self {
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Self::with_direction(content, Direction::default())
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}
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/// Creates a new [`Scrollable`] with the given [`Direction`].
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pub fn with_direction(
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content: impl Into<Element<'a, Message, Theme, Renderer>>,
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direction: impl Into<Direction>,
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) -> Self {
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Scrollable {
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id: None,
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width: Length::Shrink,
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height: Length::Shrink,
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direction: direction.into(),
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content: content.into(),
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on_scroll: None,
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class: Theme::default(),
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last_status: None,
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}
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.validate()
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}
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fn validate(mut self) -> Self {
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let size_hint = self.content.as_widget().size_hint();
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debug_assert!(
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self.direction.vertical().is_none() || !size_hint.height.is_fill(),
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"scrollable content must not fill its vertical scrolling axis"
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);
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debug_assert!(
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self.direction.horizontal().is_none() || !size_hint.width.is_fill(),
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"scrollable content must not fill its horizontal scrolling axis"
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);
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if self.direction.horizontal().is_none() {
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self.width = self.width.enclose(size_hint.width);
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}
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if self.direction.vertical().is_none() {
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self.height = self.height.enclose(size_hint.height);
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}
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self
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}
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/// Makes the [`Scrollable`] scroll horizontally, with default [`Scrollbar`] settings.
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pub fn horizontal(self) -> Self {
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self.direction(Direction::Horizontal(Scrollbar::default()))
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}
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/// Sets the [`Direction`] of the [`Scrollable`].
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pub fn direction(mut self, direction: impl Into<Direction>) -> Self {
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self.direction = direction.into();
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self.validate()
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}
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/// Sets the [`Id`] of the [`Scrollable`].
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pub fn id(mut self, id: impl Into<Id>) -> Self {
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self.id = Some(id.into());
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self
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}
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/// Sets the width of the [`Scrollable`].
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pub fn width(mut self, width: impl Into<Length>) -> Self {
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self.width = width.into();
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self
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}
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/// Sets the height of the [`Scrollable`].
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pub fn height(mut self, height: impl Into<Length>) -> Self {
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self.height = height.into();
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self
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}
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/// Sets a function to call when the [`Scrollable`] is scrolled.
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///
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/// The function takes the [`Viewport`] of the [`Scrollable`]
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pub fn on_scroll(mut self, f: impl Fn(Viewport) -> Message + 'a) -> Self {
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self.on_scroll = Some(Box::new(f));
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self
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}
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/// Anchors the vertical [`Scrollable`] direction to the top.
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pub fn anchor_top(self) -> Self {
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self.anchor_y(Anchor::Start)
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}
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/// Anchors the vertical [`Scrollable`] direction to the bottom.
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pub fn anchor_bottom(self) -> Self {
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self.anchor_y(Anchor::End)
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}
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/// Anchors the horizontal [`Scrollable`] direction to the left.
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pub fn anchor_left(self) -> Self {
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self.anchor_x(Anchor::Start)
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}
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/// Anchors the horizontal [`Scrollable`] direction to the right.
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pub fn anchor_right(self) -> Self {
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self.anchor_x(Anchor::End)
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}
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/// Sets the [`Anchor`] of the horizontal direction of the [`Scrollable`], if applicable.
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pub fn anchor_x(mut self, alignment: Anchor) -> Self {
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match &mut self.direction {
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Direction::Horizontal(horizontal)
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| Direction::Both { horizontal, .. } => {
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horizontal.alignment = alignment;
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}
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Direction::Vertical { .. } => {}
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}
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self
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}
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/// Sets the [`Anchor`] of the vertical direction of the [`Scrollable`], if applicable.
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pub fn anchor_y(mut self, alignment: Anchor) -> Self {
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match &mut self.direction {
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Direction::Vertical(vertical)
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| Direction::Both { vertical, .. } => {
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vertical.alignment = alignment;
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}
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Direction::Horizontal { .. } => {}
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}
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self
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}
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/// Embeds the [`Scrollbar`] into the [`Scrollable`], instead of floating on top of the
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/// content.
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///
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/// The `spacing` provided will be used as space between the [`Scrollbar`] and the contents
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/// of the [`Scrollable`].
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pub fn spacing(mut self, new_spacing: impl Into<Pixels>) -> Self {
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match &mut self.direction {
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Direction::Horizontal(scrollbar)
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| Direction::Vertical(scrollbar) => {
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scrollbar.spacing = Some(new_spacing.into().0);
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}
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Direction::Both { .. } => {}
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}
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self
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}
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/// Sets the style of this [`Scrollable`].
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#[must_use]
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pub fn style(mut self, style: impl Fn(&Theme, Status) -> Style + 'a) -> Self
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where
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Theme::Class<'a>: From<StyleFn<'a, Theme>>,
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{
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self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
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self
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}
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/// Sets the style class of the [`Scrollable`].
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#[cfg(feature = "advanced")]
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#[must_use]
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pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
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self.class = class.into();
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self
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}
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}
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/// The direction of [`Scrollable`].
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#[derive(Debug, Clone, Copy, PartialEq)]
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pub enum Direction {
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/// Vertical scrolling
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Vertical(Scrollbar),
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/// Horizontal scrolling
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Horizontal(Scrollbar),
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/// Both vertical and horizontal scrolling
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Both {
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/// The properties of the vertical scrollbar.
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vertical: Scrollbar,
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/// The properties of the horizontal scrollbar.
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horizontal: Scrollbar,
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},
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}
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impl Direction {
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/// Returns the horizontal [`Scrollbar`], if any.
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pub fn horizontal(&self) -> Option<&Scrollbar> {
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match self {
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Self::Horizontal(scrollbar) => Some(scrollbar),
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Self::Both { horizontal, .. } => Some(horizontal),
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Self::Vertical(_) => None,
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}
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}
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/// Returns the vertical [`Scrollbar`], if any.
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pub fn vertical(&self) -> Option<&Scrollbar> {
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match self {
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Self::Vertical(scrollbar) => Some(scrollbar),
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Self::Both { vertical, .. } => Some(vertical),
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Self::Horizontal(_) => None,
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}
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}
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fn align(&self, delta: Vector) -> Vector {
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let horizontal_alignment =
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self.horizontal().map(|p| p.alignment).unwrap_or_default();
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let vertical_alignment =
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self.vertical().map(|p| p.alignment).unwrap_or_default();
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let align = |alignment: Anchor, delta: f32| match alignment {
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Anchor::Start => delta,
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Anchor::End => -delta,
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};
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Vector::new(
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align(horizontal_alignment, delta.x),
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align(vertical_alignment, delta.y),
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)
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}
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}
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impl Default for Direction {
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fn default() -> Self {
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Self::Vertical(Scrollbar::default())
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}
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}
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/// A scrollbar within a [`Scrollable`].
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#[derive(Debug, Clone, Copy, PartialEq)]
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pub struct Scrollbar {
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width: f32,
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margin: f32,
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scroller_width: f32,
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alignment: Anchor,
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spacing: Option<f32>,
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}
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impl Default for Scrollbar {
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fn default() -> Self {
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Self {
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width: 10.0,
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margin: 0.0,
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scroller_width: 10.0,
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alignment: Anchor::Start,
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spacing: None,
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}
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}
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}
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impl Scrollbar {
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/// Creates new [`Scrollbar`] for use in a [`Scrollable`].
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pub fn new() -> Self {
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Self::default()
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}
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/// Sets the scrollbar width of the [`Scrollbar`] .
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pub fn width(mut self, width: impl Into<Pixels>) -> Self {
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self.width = width.into().0.max(0.0);
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self
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}
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/// Sets the scrollbar margin of the [`Scrollbar`] .
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pub fn margin(mut self, margin: impl Into<Pixels>) -> Self {
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self.margin = margin.into().0;
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self
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}
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/// Sets the scroller width of the [`Scrollbar`] .
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pub fn scroller_width(mut self, scroller_width: impl Into<Pixels>) -> Self {
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self.scroller_width = scroller_width.into().0.max(0.0);
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self
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}
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/// Sets the [`Anchor`] of the [`Scrollbar`] .
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pub fn anchor(mut self, alignment: Anchor) -> Self {
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self.alignment = alignment;
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self
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}
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/// Sets whether the [`Scrollbar`] should be embedded in the [`Scrollable`], using
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/// the given spacing between itself and the contents.
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///
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/// An embedded [`Scrollbar`] will always be displayed, will take layout space,
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/// and will not float over the contents.
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pub fn spacing(mut self, spacing: impl Into<Pixels>) -> Self {
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self.spacing = Some(spacing.into().0);
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self
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}
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}
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/// The anchor of the scroller of the [`Scrollable`] relative to its [`Viewport`]
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/// on a given axis.
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#[derive(Debug, Clone, Copy, Default, PartialEq, Eq)]
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pub enum Anchor {
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/// Scroller is anchoer to the start of the [`Viewport`].
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#[default]
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Start,
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/// Content is aligned to the end of the [`Viewport`].
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End,
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}
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impl<Message, Theme, Renderer> Widget<Message, Theme, Renderer>
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for Scrollable<'_, Message, Theme, Renderer>
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where
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Theme: Catalog,
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Renderer: core::Renderer,
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{
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fn tag(&self) -> tree::Tag {
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tree::Tag::of::<State>()
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}
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fn state(&self) -> tree::State {
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tree::State::new(State::new())
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}
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fn children(&self) -> Vec<Tree> {
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vec![Tree::new(&self.content)]
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}
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fn diff(&self, tree: &mut Tree) {
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tree.diff_children(std::slice::from_ref(&self.content));
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}
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fn size(&self) -> Size<Length> {
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Size {
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width: self.width,
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height: self.height,
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}
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}
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fn layout(
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&self,
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tree: &mut Tree,
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renderer: &Renderer,
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limits: &layout::Limits,
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) -> layout::Node {
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let (right_padding, bottom_padding) = match self.direction {
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Direction::Vertical(Scrollbar {
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width,
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margin,
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spacing: Some(spacing),
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..
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}) => (width + margin * 2.0 + spacing, 0.0),
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Direction::Horizontal(Scrollbar {
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width,
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margin,
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spacing: Some(spacing),
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..
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}) => (0.0, width + margin * 2.0 + spacing),
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_ => (0.0, 0.0),
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};
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layout::padded(
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limits,
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self.width,
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self.height,
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Padding {
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right: right_padding,
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bottom: bottom_padding,
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..Padding::ZERO
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},
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|limits| {
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let child_limits = layout::Limits::new(
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Size::new(limits.min().width, limits.min().height),
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Size::new(
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if self.direction.horizontal().is_some() {
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f32::INFINITY
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} else {
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limits.max().width
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},
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if self.direction.vertical().is_some() {
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f32::MAX
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} else {
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limits.max().height
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},
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),
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);
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self.content.as_widget().layout(
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&mut tree.children[0],
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renderer,
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&child_limits,
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)
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},
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)
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}
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|
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fn operate(
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&self,
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tree: &mut Tree,
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layout: Layout<'_>,
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renderer: &Renderer,
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operation: &mut dyn Operation,
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) {
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let state = tree.state.downcast_mut::<State>();
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let bounds = layout.bounds();
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let content_layout = layout.children().next().unwrap();
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let content_bounds = content_layout.bounds();
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let translation =
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state.translation(self.direction, bounds, content_bounds);
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operation.scrollable(
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self.id.as_ref().map(|id| &id.0),
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bounds,
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content_bounds,
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translation,
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state,
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);
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|
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operation.container(
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self.id.as_ref().map(|id| &id.0),
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bounds,
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&mut |operation| {
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self.content.as_widget().operate(
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&mut tree.children[0],
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layout.children().next().unwrap(),
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renderer,
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operation,
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);
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},
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);
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}
|
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|
|
fn update(
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&mut self,
|
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tree: &mut Tree,
|
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event: &Event,
|
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layout: Layout<'_>,
|
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cursor: mouse::Cursor,
|
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renderer: &Renderer,
|
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clipboard: &mut dyn Clipboard,
|
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shell: &mut Shell<'_, Message>,
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_viewport: &Rectangle,
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) {
|
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let state = tree.state.downcast_mut::<State>();
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let bounds = layout.bounds();
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let cursor_over_scrollable = cursor.position_over(bounds);
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let content = layout.children().next().unwrap();
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let content_bounds = content.bounds();
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let scrollbars =
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Scrollbars::new(state, self.direction, bounds, content_bounds);
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|
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let (mouse_over_y_scrollbar, mouse_over_x_scrollbar) =
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scrollbars.is_mouse_over(cursor);
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let last_offsets = (state.offset_x, state.offset_y);
|
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|
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if let Some(last_scrolled) = state.last_scrolled {
|
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let clear_transaction = match event {
|
|
Event::Mouse(
|
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mouse::Event::ButtonPressed(_)
|
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| mouse::Event::ButtonReleased(_)
|
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| mouse::Event::CursorLeft,
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) => true,
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Event::Mouse(mouse::Event::CursorMoved { .. }) => {
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last_scrolled.elapsed() > Duration::from_millis(100)
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}
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_ => last_scrolled.elapsed() > Duration::from_millis(1500),
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};
|
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|
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if clear_transaction {
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state.last_scrolled = None;
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}
|
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}
|
|
|
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let mut update = || {
|
|
if let Some(scroller_grabbed_at) = state.y_scroller_grabbed_at {
|
|
match event {
|
|
Event::Mouse(mouse::Event::CursorMoved { .. })
|
|
| Event::Touch(touch::Event::FingerMoved { .. }) => {
|
|
if let Some(scrollbar) = scrollbars.y {
|
|
let Some(cursor_position) =
|
|
cursor.land().position()
|
|
else {
|
|
return;
|
|
};
|
|
|
|
state.scroll_y_to(
|
|
scrollbar.scroll_percentage_y(
|
|
scroller_grabbed_at,
|
|
cursor_position,
|
|
),
|
|
bounds,
|
|
content_bounds,
|
|
);
|
|
|
|
let _ = notify_scroll(
|
|
state,
|
|
&self.on_scroll,
|
|
bounds,
|
|
content_bounds,
|
|
shell,
|
|
);
|
|
|
|
shell.capture_event();
|
|
}
|
|
}
|
|
_ => {}
|
|
}
|
|
} else if mouse_over_y_scrollbar {
|
|
match event {
|
|
Event::Mouse(mouse::Event::ButtonPressed(
|
|
mouse::Button::Left,
|
|
))
|
|
| Event::Touch(touch::Event::FingerPressed { .. }) => {
|
|
let Some(cursor_position) = cursor.position() else {
|
|
return;
|
|
};
|
|
|
|
if let (Some(scroller_grabbed_at), Some(scrollbar)) = (
|
|
scrollbars.grab_y_scroller(cursor_position),
|
|
scrollbars.y,
|
|
) {
|
|
state.scroll_y_to(
|
|
scrollbar.scroll_percentage_y(
|
|
scroller_grabbed_at,
|
|
cursor_position,
|
|
),
|
|
bounds,
|
|
content_bounds,
|
|
);
|
|
|
|
state.y_scroller_grabbed_at =
|
|
Some(scroller_grabbed_at);
|
|
|
|
let _ = notify_scroll(
|
|
state,
|
|
&self.on_scroll,
|
|
bounds,
|
|
content_bounds,
|
|
shell,
|
|
);
|
|
}
|
|
|
|
shell.capture_event();
|
|
}
|
|
_ => {}
|
|
}
|
|
}
|
|
|
|
if let Some(scroller_grabbed_at) = state.x_scroller_grabbed_at {
|
|
match event {
|
|
Event::Mouse(mouse::Event::CursorMoved { .. })
|
|
| Event::Touch(touch::Event::FingerMoved { .. }) => {
|
|
let Some(cursor_position) = cursor.land().position()
|
|
else {
|
|
return;
|
|
};
|
|
|
|
if let Some(scrollbar) = scrollbars.x {
|
|
state.scroll_x_to(
|
|
scrollbar.scroll_percentage_x(
|
|
scroller_grabbed_at,
|
|
cursor_position,
|
|
),
|
|
bounds,
|
|
content_bounds,
|
|
);
|
|
|
|
let _ = notify_scroll(
|
|
state,
|
|
&self.on_scroll,
|
|
bounds,
|
|
content_bounds,
|
|
shell,
|
|
);
|
|
}
|
|
|
|
shell.capture_event();
|
|
}
|
|
_ => {}
|
|
}
|
|
} else if mouse_over_x_scrollbar {
|
|
match event {
|
|
Event::Mouse(mouse::Event::ButtonPressed(
|
|
mouse::Button::Left,
|
|
))
|
|
| Event::Touch(touch::Event::FingerPressed { .. }) => {
|
|
let Some(cursor_position) = cursor.position() else {
|
|
return;
|
|
};
|
|
|
|
if let (Some(scroller_grabbed_at), Some(scrollbar)) = (
|
|
scrollbars.grab_x_scroller(cursor_position),
|
|
scrollbars.x,
|
|
) {
|
|
state.scroll_x_to(
|
|
scrollbar.scroll_percentage_x(
|
|
scroller_grabbed_at,
|
|
cursor_position,
|
|
),
|
|
bounds,
|
|
content_bounds,
|
|
);
|
|
|
|
state.x_scroller_grabbed_at =
|
|
Some(scroller_grabbed_at);
|
|
|
|
let _ = notify_scroll(
|
|
state,
|
|
&self.on_scroll,
|
|
bounds,
|
|
content_bounds,
|
|
shell,
|
|
);
|
|
|
|
shell.capture_event();
|
|
}
|
|
}
|
|
_ => {}
|
|
}
|
|
}
|
|
|
|
if state.last_scrolled.is_none()
|
|
|| !matches!(
|
|
event,
|
|
Event::Mouse(mouse::Event::WheelScrolled { .. })
|
|
)
|
|
{
|
|
let cursor = match cursor_over_scrollable {
|
|
Some(cursor_position)
|
|
if !(mouse_over_x_scrollbar
|
|
|| mouse_over_y_scrollbar) =>
|
|
{
|
|
mouse::Cursor::Available(
|
|
cursor_position
|
|
+ state.translation(
|
|
self.direction,
|
|
bounds,
|
|
content_bounds,
|
|
),
|
|
)
|
|
}
|
|
_ => mouse::Cursor::Unavailable,
|
|
};
|
|
|
|
let had_input_method = shell.input_method().is_enabled();
|
|
|
|
let translation =
|
|
state.translation(self.direction, bounds, content_bounds);
|
|
|
|
self.content.as_widget_mut().update(
|
|
&mut tree.children[0],
|
|
event,
|
|
content,
|
|
cursor,
|
|
renderer,
|
|
clipboard,
|
|
shell,
|
|
&Rectangle {
|
|
y: bounds.y + translation.y,
|
|
x: bounds.x + translation.x,
|
|
..bounds
|
|
},
|
|
);
|
|
|
|
if !had_input_method {
|
|
if let InputMethod::Enabled { position, .. } =
|
|
shell.input_method_mut()
|
|
{
|
|
*position = *position - translation;
|
|
}
|
|
}
|
|
};
|
|
|
|
if matches!(
|
|
event,
|
|
Event::Mouse(mouse::Event::ButtonReleased(mouse::Button::Left))
|
|
| Event::Touch(
|
|
touch::Event::FingerLifted { .. }
|
|
| touch::Event::FingerLost { .. }
|
|
)
|
|
) {
|
|
state.scroll_area_touched_at = None;
|
|
state.x_scroller_grabbed_at = None;
|
|
state.y_scroller_grabbed_at = None;
|
|
|
|
return;
|
|
}
|
|
|
|
if shell.is_event_captured() {
|
|
return;
|
|
}
|
|
|
|
if let Event::Keyboard(keyboard::Event::ModifiersChanged(
|
|
modifiers,
|
|
)) = event
|
|
{
|
|
state.keyboard_modifiers = *modifiers;
|
|
|
|
return;
|
|
}
|
|
|
|
match event {
|
|
Event::Mouse(mouse::Event::WheelScrolled { delta }) => {
|
|
if cursor_over_scrollable.is_none() {
|
|
return;
|
|
}
|
|
|
|
let delta = match *delta {
|
|
mouse::ScrollDelta::Lines { x, y } => {
|
|
let is_shift_pressed =
|
|
state.keyboard_modifiers.shift();
|
|
|
|
// macOS automatically inverts the axes when Shift is pressed
|
|
let (x, y) = if cfg!(target_os = "macos")
|
|
&& is_shift_pressed
|
|
{
|
|
(y, x)
|
|
} else {
|
|
(x, y)
|
|
};
|
|
|
|
let movement = if !is_shift_pressed {
|
|
Vector::new(x, y)
|
|
} else {
|
|
Vector::new(y, x)
|
|
};
|
|
|
|
// TODO: Configurable speed/friction (?)
|
|
-movement * 60.0
|
|
}
|
|
mouse::ScrollDelta::Pixels { x, y } => {
|
|
-Vector::new(x, y)
|
|
}
|
|
};
|
|
|
|
state.scroll(
|
|
self.direction.align(delta),
|
|
bounds,
|
|
content_bounds,
|
|
);
|
|
|
|
let has_scrolled = notify_scroll(
|
|
state,
|
|
&self.on_scroll,
|
|
bounds,
|
|
content_bounds,
|
|
shell,
|
|
);
|
|
|
|
let in_transaction = state.last_scrolled.is_some();
|
|
|
|
if has_scrolled || in_transaction {
|
|
shell.capture_event();
|
|
}
|
|
}
|
|
Event::Touch(event)
|
|
if state.scroll_area_touched_at.is_some()
|
|
|| !mouse_over_y_scrollbar
|
|
&& !mouse_over_x_scrollbar =>
|
|
{
|
|
match event {
|
|
touch::Event::FingerPressed { .. } => {
|
|
let Some(cursor_position) = cursor.position()
|
|
else {
|
|
return;
|
|
};
|
|
|
|
state.scroll_area_touched_at =
|
|
Some(cursor_position);
|
|
}
|
|
touch::Event::FingerMoved { .. } => {
|
|
if let Some(scroll_box_touched_at) =
|
|
state.scroll_area_touched_at
|
|
{
|
|
let Some(cursor_position) = cursor.position()
|
|
else {
|
|
return;
|
|
};
|
|
|
|
let delta = Vector::new(
|
|
scroll_box_touched_at.x - cursor_position.x,
|
|
scroll_box_touched_at.y - cursor_position.y,
|
|
);
|
|
|
|
state.scroll(
|
|
self.direction.align(delta),
|
|
bounds,
|
|
content_bounds,
|
|
);
|
|
|
|
state.scroll_area_touched_at =
|
|
Some(cursor_position);
|
|
|
|
// TODO: bubble up touch movements if not consumed.
|
|
let _ = notify_scroll(
|
|
state,
|
|
&self.on_scroll,
|
|
bounds,
|
|
content_bounds,
|
|
shell,
|
|
);
|
|
}
|
|
}
|
|
_ => {}
|
|
}
|
|
|
|
shell.capture_event();
|
|
}
|
|
Event::Window(window::Event::RedrawRequested(_)) => {
|
|
let _ = notify_viewport(
|
|
state,
|
|
&self.on_scroll,
|
|
bounds,
|
|
content_bounds,
|
|
shell,
|
|
);
|
|
}
|
|
_ => {}
|
|
}
|
|
};
|
|
|
|
update();
|
|
|
|
let status = if state.y_scroller_grabbed_at.is_some()
|
|
|| state.x_scroller_grabbed_at.is_some()
|
|
{
|
|
Status::Dragged {
|
|
is_horizontal_scrollbar_dragged: state
|
|
.x_scroller_grabbed_at
|
|
.is_some(),
|
|
is_vertical_scrollbar_dragged: state
|
|
.y_scroller_grabbed_at
|
|
.is_some(),
|
|
is_horizontal_scrollbar_disabled: scrollbars.is_x_disabled(),
|
|
is_vertical_scrollbar_disabled: scrollbars.is_y_disabled(),
|
|
}
|
|
} else if cursor_over_scrollable.is_some() {
|
|
Status::Hovered {
|
|
is_horizontal_scrollbar_hovered: mouse_over_x_scrollbar,
|
|
is_vertical_scrollbar_hovered: mouse_over_y_scrollbar,
|
|
is_horizontal_scrollbar_disabled: scrollbars.is_x_disabled(),
|
|
is_vertical_scrollbar_disabled: scrollbars.is_y_disabled(),
|
|
}
|
|
} else {
|
|
Status::Active {
|
|
is_horizontal_scrollbar_disabled: scrollbars.is_x_disabled(),
|
|
is_vertical_scrollbar_disabled: scrollbars.is_y_disabled(),
|
|
}
|
|
};
|
|
|
|
if let Event::Window(window::Event::RedrawRequested(_now)) = event {
|
|
self.last_status = Some(status);
|
|
}
|
|
|
|
if last_offsets != (state.offset_x, state.offset_y)
|
|
|| self
|
|
.last_status
|
|
.is_some_and(|last_status| last_status != status)
|
|
{
|
|
shell.request_redraw();
|
|
}
|
|
}
|
|
|
|
fn draw(
|
|
&self,
|
|
tree: &Tree,
|
|
renderer: &mut Renderer,
|
|
theme: &Theme,
|
|
defaults: &renderer::Style,
|
|
layout: Layout<'_>,
|
|
cursor: mouse::Cursor,
|
|
viewport: &Rectangle,
|
|
) {
|
|
let state = tree.state.downcast_ref::<State>();
|
|
|
|
let bounds = layout.bounds();
|
|
let content_layout = layout.children().next().unwrap();
|
|
let content_bounds = content_layout.bounds();
|
|
|
|
let Some(visible_bounds) = bounds.intersection(viewport) else {
|
|
return;
|
|
};
|
|
|
|
let scrollbars =
|
|
Scrollbars::new(state, self.direction, bounds, content_bounds);
|
|
|
|
let cursor_over_scrollable = cursor.position_over(bounds);
|
|
let (mouse_over_y_scrollbar, mouse_over_x_scrollbar) =
|
|
scrollbars.is_mouse_over(cursor);
|
|
|
|
let translation =
|
|
state.translation(self.direction, bounds, content_bounds);
|
|
|
|
let cursor = match cursor_over_scrollable {
|
|
Some(cursor_position)
|
|
if !(mouse_over_x_scrollbar || mouse_over_y_scrollbar) =>
|
|
{
|
|
mouse::Cursor::Available(cursor_position + translation)
|
|
}
|
|
_ => mouse::Cursor::Unavailable,
|
|
};
|
|
|
|
let style = theme.style(
|
|
&self.class,
|
|
self.last_status.unwrap_or(Status::Active {
|
|
is_horizontal_scrollbar_disabled: false,
|
|
is_vertical_scrollbar_disabled: false,
|
|
}),
|
|
);
|
|
|
|
container::draw_background(renderer, &style.container, layout.bounds());
|
|
|
|
// Draw inner content
|
|
if scrollbars.active() {
|
|
renderer.with_layer(visible_bounds, |renderer| {
|
|
renderer.with_translation(
|
|
Vector::new(-translation.x, -translation.y),
|
|
|renderer| {
|
|
self.content.as_widget().draw(
|
|
&tree.children[0],
|
|
renderer,
|
|
theme,
|
|
defaults,
|
|
content_layout,
|
|
cursor,
|
|
&Rectangle {
|
|
y: visible_bounds.y + translation.y,
|
|
x: visible_bounds.x + translation.x,
|
|
..visible_bounds
|
|
},
|
|
);
|
|
},
|
|
);
|
|
});
|
|
|
|
let draw_scrollbar =
|
|
|renderer: &mut Renderer,
|
|
style: Rail,
|
|
scrollbar: &internals::Scrollbar| {
|
|
if scrollbar.bounds.width > 0.0
|
|
&& scrollbar.bounds.height > 0.0
|
|
&& (style.background.is_some()
|
|
|| (style.border.color != Color::TRANSPARENT
|
|
&& style.border.width > 0.0))
|
|
{
|
|
renderer.fill_quad(
|
|
renderer::Quad {
|
|
bounds: scrollbar.bounds,
|
|
border: style.border,
|
|
..renderer::Quad::default()
|
|
},
|
|
style.background.unwrap_or(Background::Color(
|
|
Color::TRANSPARENT,
|
|
)),
|
|
);
|
|
}
|
|
|
|
if let Some(scroller) = scrollbar.scroller {
|
|
if scroller.bounds.width > 0.0
|
|
&& scroller.bounds.height > 0.0
|
|
&& (style.scroller.color != Color::TRANSPARENT
|
|
|| (style.scroller.border.color
|
|
!= Color::TRANSPARENT
|
|
&& style.scroller.border.width > 0.0))
|
|
{
|
|
renderer.fill_quad(
|
|
renderer::Quad {
|
|
bounds: scroller.bounds,
|
|
border: style.scroller.border,
|
|
..renderer::Quad::default()
|
|
},
|
|
style.scroller.color,
|
|
);
|
|
}
|
|
}
|
|
};
|
|
|
|
renderer.with_layer(
|
|
Rectangle {
|
|
width: (visible_bounds.width + 2.0).min(viewport.width),
|
|
height: (visible_bounds.height + 2.0).min(viewport.height),
|
|
..visible_bounds
|
|
},
|
|
|renderer| {
|
|
if let Some(scrollbar) = scrollbars.y {
|
|
draw_scrollbar(
|
|
renderer,
|
|
style.vertical_rail,
|
|
&scrollbar,
|
|
);
|
|
}
|
|
|
|
if let Some(scrollbar) = scrollbars.x {
|
|
draw_scrollbar(
|
|
renderer,
|
|
style.horizontal_rail,
|
|
&scrollbar,
|
|
);
|
|
}
|
|
|
|
if let (Some(x), Some(y)) = (scrollbars.x, scrollbars.y) {
|
|
let background =
|
|
style.gap.or(style.container.background);
|
|
|
|
if let Some(background) = background {
|
|
renderer.fill_quad(
|
|
renderer::Quad {
|
|
bounds: Rectangle {
|
|
x: y.bounds.x,
|
|
y: x.bounds.y,
|
|
width: y.bounds.width,
|
|
height: x.bounds.height,
|
|
},
|
|
..renderer::Quad::default()
|
|
},
|
|
background,
|
|
);
|
|
}
|
|
}
|
|
},
|
|
);
|
|
} else {
|
|
self.content.as_widget().draw(
|
|
&tree.children[0],
|
|
renderer,
|
|
theme,
|
|
defaults,
|
|
content_layout,
|
|
cursor,
|
|
&Rectangle {
|
|
x: visible_bounds.x + translation.x,
|
|
y: visible_bounds.y + translation.y,
|
|
..visible_bounds
|
|
},
|
|
);
|
|
}
|
|
}
|
|
|
|
fn mouse_interaction(
|
|
&self,
|
|
tree: &Tree,
|
|
layout: Layout<'_>,
|
|
cursor: mouse::Cursor,
|
|
_viewport: &Rectangle,
|
|
renderer: &Renderer,
|
|
) -> mouse::Interaction {
|
|
let state = tree.state.downcast_ref::<State>();
|
|
let bounds = layout.bounds();
|
|
let cursor_over_scrollable = cursor.position_over(bounds);
|
|
|
|
let content_layout = layout.children().next().unwrap();
|
|
let content_bounds = content_layout.bounds();
|
|
|
|
let scrollbars =
|
|
Scrollbars::new(state, self.direction, bounds, content_bounds);
|
|
|
|
let (mouse_over_y_scrollbar, mouse_over_x_scrollbar) =
|
|
scrollbars.is_mouse_over(cursor);
|
|
|
|
if (mouse_over_x_scrollbar || mouse_over_y_scrollbar)
|
|
|| state.scrollers_grabbed()
|
|
{
|
|
mouse::Interaction::None
|
|
} else {
|
|
let translation =
|
|
state.translation(self.direction, bounds, content_bounds);
|
|
|
|
let cursor = match cursor_over_scrollable {
|
|
Some(cursor_position)
|
|
if !(mouse_over_x_scrollbar || mouse_over_y_scrollbar) =>
|
|
{
|
|
mouse::Cursor::Available(cursor_position + translation)
|
|
}
|
|
_ => mouse::Cursor::Unavailable,
|
|
};
|
|
|
|
self.content.as_widget().mouse_interaction(
|
|
&tree.children[0],
|
|
content_layout,
|
|
cursor,
|
|
&Rectangle {
|
|
y: bounds.y + translation.y,
|
|
x: bounds.x + translation.x,
|
|
..bounds
|
|
},
|
|
renderer,
|
|
)
|
|
}
|
|
}
|
|
|
|
fn overlay<'b>(
|
|
&'b mut self,
|
|
tree: &'b mut Tree,
|
|
layout: Layout<'_>,
|
|
renderer: &Renderer,
|
|
translation: Vector,
|
|
) -> Option<overlay::Element<'b, Message, Theme, Renderer>> {
|
|
let bounds = layout.bounds();
|
|
let content_layout = layout.children().next().unwrap();
|
|
let content_bounds = content_layout.bounds();
|
|
|
|
let offset = tree.state.downcast_ref::<State>().translation(
|
|
self.direction,
|
|
bounds,
|
|
content_bounds,
|
|
);
|
|
|
|
self.content.as_widget_mut().overlay(
|
|
&mut tree.children[0],
|
|
layout.children().next().unwrap(),
|
|
renderer,
|
|
translation - offset,
|
|
)
|
|
}
|
|
}
|
|
|
|
impl<'a, Message, Theme, Renderer>
|
|
From<Scrollable<'a, Message, Theme, Renderer>>
|
|
for Element<'a, Message, Theme, Renderer>
|
|
where
|
|
Message: 'a,
|
|
Theme: 'a + Catalog,
|
|
Renderer: 'a + core::Renderer,
|
|
{
|
|
fn from(
|
|
text_input: Scrollable<'a, Message, Theme, Renderer>,
|
|
) -> Element<'a, Message, Theme, Renderer> {
|
|
Element::new(text_input)
|
|
}
|
|
}
|
|
|
|
/// The identifier of a [`Scrollable`].
|
|
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
|
|
pub struct Id(widget::Id);
|
|
|
|
impl Id {
|
|
/// Creates a custom [`Id`].
|
|
pub fn new(id: impl Into<std::borrow::Cow<'static, str>>) -> Self {
|
|
Self(widget::Id::new(id))
|
|
}
|
|
|
|
/// Creates a unique [`Id`].
|
|
///
|
|
/// This function produces a different [`Id`] every time it is called.
|
|
pub fn unique() -> Self {
|
|
Self(widget::Id::unique())
|
|
}
|
|
}
|
|
|
|
impl From<Id> for widget::Id {
|
|
fn from(id: Id) -> Self {
|
|
id.0
|
|
}
|
|
}
|
|
|
|
impl From<&'static str> for Id {
|
|
fn from(id: &'static str) -> Self {
|
|
Self::new(id)
|
|
}
|
|
}
|
|
|
|
/// Produces a [`Task`] that snaps the [`Scrollable`] with the given [`Id`]
|
|
/// to the provided [`RelativeOffset`].
|
|
pub fn snap_to<T>(id: impl Into<Id>, offset: RelativeOffset) -> Task<T> {
|
|
task::effect(Action::widget(operation::scrollable::snap_to(
|
|
id.into().0,
|
|
offset,
|
|
)))
|
|
}
|
|
|
|
/// Produces a [`Task`] that scrolls the [`Scrollable`] with the given [`Id`]
|
|
/// to the provided [`AbsoluteOffset`].
|
|
pub fn scroll_to<T>(id: impl Into<Id>, offset: AbsoluteOffset) -> Task<T> {
|
|
task::effect(Action::widget(operation::scrollable::scroll_to(
|
|
id.into().0,
|
|
offset,
|
|
)))
|
|
}
|
|
|
|
/// Produces a [`Task`] that scrolls the [`Scrollable`] with the given [`Id`]
|
|
/// by the provided [`AbsoluteOffset`].
|
|
pub fn scroll_by<T>(id: impl Into<Id>, offset: AbsoluteOffset) -> Task<T> {
|
|
task::effect(Action::widget(operation::scrollable::scroll_by(
|
|
id.into().0,
|
|
offset,
|
|
)))
|
|
}
|
|
|
|
fn notify_scroll<Message>(
|
|
state: &mut State,
|
|
on_scroll: &Option<Box<dyn Fn(Viewport) -> Message + '_>>,
|
|
bounds: Rectangle,
|
|
content_bounds: Rectangle,
|
|
shell: &mut Shell<'_, Message>,
|
|
) -> bool {
|
|
if notify_viewport(state, on_scroll, bounds, content_bounds, shell) {
|
|
state.last_scrolled = Some(Instant::now());
|
|
|
|
true
|
|
} else {
|
|
false
|
|
}
|
|
}
|
|
|
|
fn notify_viewport<Message>(
|
|
state: &mut State,
|
|
on_scroll: &Option<Box<dyn Fn(Viewport) -> Message + '_>>,
|
|
bounds: Rectangle,
|
|
content_bounds: Rectangle,
|
|
shell: &mut Shell<'_, Message>,
|
|
) -> bool {
|
|
if content_bounds.width <= bounds.width
|
|
&& content_bounds.height <= bounds.height
|
|
{
|
|
return false;
|
|
}
|
|
|
|
let viewport = Viewport {
|
|
offset_x: state.offset_x,
|
|
offset_y: state.offset_y,
|
|
bounds,
|
|
content_bounds,
|
|
};
|
|
|
|
// Don't publish redundant viewports to shell
|
|
if let Some(last_notified) = state.last_notified {
|
|
let last_relative_offset = last_notified.relative_offset();
|
|
let current_relative_offset = viewport.relative_offset();
|
|
|
|
let last_absolute_offset = last_notified.absolute_offset();
|
|
let current_absolute_offset = viewport.absolute_offset();
|
|
|
|
let unchanged = |a: f32, b: f32| {
|
|
(a - b).abs() <= f32::EPSILON || (a.is_nan() && b.is_nan())
|
|
};
|
|
|
|
if last_notified.bounds == bounds
|
|
&& last_notified.content_bounds == content_bounds
|
|
&& unchanged(last_relative_offset.x, current_relative_offset.x)
|
|
&& unchanged(last_relative_offset.y, current_relative_offset.y)
|
|
&& unchanged(last_absolute_offset.x, current_absolute_offset.x)
|
|
&& unchanged(last_absolute_offset.y, current_absolute_offset.y)
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
|
|
state.last_notified = Some(viewport);
|
|
|
|
if let Some(on_scroll) = on_scroll {
|
|
shell.publish(on_scroll(viewport));
|
|
}
|
|
|
|
true
|
|
}
|
|
|
|
#[derive(Debug, Clone, Copy)]
|
|
struct State {
|
|
scroll_area_touched_at: Option<Point>,
|
|
offset_y: Offset,
|
|
y_scroller_grabbed_at: Option<f32>,
|
|
offset_x: Offset,
|
|
x_scroller_grabbed_at: Option<f32>,
|
|
keyboard_modifiers: keyboard::Modifiers,
|
|
last_notified: Option<Viewport>,
|
|
last_scrolled: Option<Instant>,
|
|
}
|
|
|
|
impl Default for State {
|
|
fn default() -> Self {
|
|
Self {
|
|
scroll_area_touched_at: None,
|
|
offset_y: Offset::Absolute(0.0),
|
|
y_scroller_grabbed_at: None,
|
|
offset_x: Offset::Absolute(0.0),
|
|
x_scroller_grabbed_at: None,
|
|
keyboard_modifiers: keyboard::Modifiers::default(),
|
|
last_notified: None,
|
|
last_scrolled: None,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl operation::Scrollable for State {
|
|
fn snap_to(&mut self, offset: RelativeOffset) {
|
|
State::snap_to(self, offset);
|
|
}
|
|
|
|
fn scroll_to(&mut self, offset: AbsoluteOffset) {
|
|
State::scroll_to(self, offset);
|
|
}
|
|
|
|
fn scroll_by(
|
|
&mut self,
|
|
offset: AbsoluteOffset,
|
|
bounds: Rectangle,
|
|
content_bounds: Rectangle,
|
|
) {
|
|
State::scroll_by(self, offset, bounds, content_bounds);
|
|
}
|
|
}
|
|
|
|
#[derive(Debug, Clone, Copy, PartialEq)]
|
|
enum Offset {
|
|
Absolute(f32),
|
|
Relative(f32),
|
|
}
|
|
|
|
impl Offset {
|
|
fn absolute(self, viewport: f32, content: f32) -> f32 {
|
|
match self {
|
|
Offset::Absolute(absolute) => {
|
|
absolute.min((content - viewport).max(0.0))
|
|
}
|
|
Offset::Relative(percentage) => {
|
|
((content - viewport) * percentage).max(0.0)
|
|
}
|
|
}
|
|
}
|
|
|
|
fn translation(
|
|
self,
|
|
viewport: f32,
|
|
content: f32,
|
|
alignment: Anchor,
|
|
) -> f32 {
|
|
let offset = self.absolute(viewport, content);
|
|
|
|
match alignment {
|
|
Anchor::Start => offset,
|
|
Anchor::End => ((content - viewport).max(0.0) - offset).max(0.0),
|
|
}
|
|
}
|
|
}
|
|
|
|
/// The current [`Viewport`] of the [`Scrollable`].
|
|
#[derive(Debug, Clone, Copy)]
|
|
pub struct Viewport {
|
|
offset_x: Offset,
|
|
offset_y: Offset,
|
|
bounds: Rectangle,
|
|
content_bounds: Rectangle,
|
|
}
|
|
|
|
impl Viewport {
|
|
/// Returns the [`AbsoluteOffset`] of the current [`Viewport`].
|
|
pub fn absolute_offset(&self) -> AbsoluteOffset {
|
|
let x = self
|
|
.offset_x
|
|
.absolute(self.bounds.width, self.content_bounds.width);
|
|
let y = self
|
|
.offset_y
|
|
.absolute(self.bounds.height, self.content_bounds.height);
|
|
|
|
AbsoluteOffset { x, y }
|
|
}
|
|
|
|
/// Returns the [`AbsoluteOffset`] of the current [`Viewport`], but with its
|
|
/// alignment reversed.
|
|
///
|
|
/// This method can be useful to switch the alignment of a [`Scrollable`]
|
|
/// while maintaining its scrolling position.
|
|
pub fn absolute_offset_reversed(&self) -> AbsoluteOffset {
|
|
let AbsoluteOffset { x, y } = self.absolute_offset();
|
|
|
|
AbsoluteOffset {
|
|
x: (self.content_bounds.width - self.bounds.width).max(0.0) - x,
|
|
y: (self.content_bounds.height - self.bounds.height).max(0.0) - y,
|
|
}
|
|
}
|
|
|
|
/// Returns the [`RelativeOffset`] of the current [`Viewport`].
|
|
pub fn relative_offset(&self) -> RelativeOffset {
|
|
let AbsoluteOffset { x, y } = self.absolute_offset();
|
|
|
|
let x = x / (self.content_bounds.width - self.bounds.width);
|
|
let y = y / (self.content_bounds.height - self.bounds.height);
|
|
|
|
RelativeOffset { x, y }
|
|
}
|
|
|
|
/// Returns the bounds of the current [`Viewport`].
|
|
pub fn bounds(&self) -> Rectangle {
|
|
self.bounds
|
|
}
|
|
|
|
/// Returns the content bounds of the current [`Viewport`].
|
|
pub fn content_bounds(&self) -> Rectangle {
|
|
self.content_bounds
|
|
}
|
|
}
|
|
|
|
impl State {
|
|
/// Creates a new [`State`] with the scrollbar(s) at the beginning.
|
|
pub fn new() -> Self {
|
|
State::default()
|
|
}
|
|
|
|
/// Apply a scrolling offset to the current [`State`], given the bounds of
|
|
/// the [`Scrollable`] and its contents.
|
|
pub fn scroll(
|
|
&mut self,
|
|
delta: Vector<f32>,
|
|
bounds: Rectangle,
|
|
content_bounds: Rectangle,
|
|
) {
|
|
if bounds.height < content_bounds.height {
|
|
self.offset_y = Offset::Absolute(
|
|
(self.offset_y.absolute(bounds.height, content_bounds.height)
|
|
+ delta.y)
|
|
.clamp(0.0, content_bounds.height - bounds.height),
|
|
);
|
|
}
|
|
|
|
if bounds.width < content_bounds.width {
|
|
self.offset_x = Offset::Absolute(
|
|
(self.offset_x.absolute(bounds.width, content_bounds.width)
|
|
+ delta.x)
|
|
.clamp(0.0, content_bounds.width - bounds.width),
|
|
);
|
|
}
|
|
}
|
|
|
|
/// Scrolls the [`Scrollable`] to a relative amount along the y axis.
|
|
///
|
|
/// `0` represents scrollbar at the beginning, while `1` represents scrollbar at
|
|
/// the end.
|
|
pub fn scroll_y_to(
|
|
&mut self,
|
|
percentage: f32,
|
|
bounds: Rectangle,
|
|
content_bounds: Rectangle,
|
|
) {
|
|
self.offset_y = Offset::Relative(percentage.clamp(0.0, 1.0));
|
|
self.unsnap(bounds, content_bounds);
|
|
}
|
|
|
|
/// Scrolls the [`Scrollable`] to a relative amount along the x axis.
|
|
///
|
|
/// `0` represents scrollbar at the beginning, while `1` represents scrollbar at
|
|
/// the end.
|
|
pub fn scroll_x_to(
|
|
&mut self,
|
|
percentage: f32,
|
|
bounds: Rectangle,
|
|
content_bounds: Rectangle,
|
|
) {
|
|
self.offset_x = Offset::Relative(percentage.clamp(0.0, 1.0));
|
|
self.unsnap(bounds, content_bounds);
|
|
}
|
|
|
|
/// Snaps the scroll position to a [`RelativeOffset`].
|
|
pub fn snap_to(&mut self, offset: RelativeOffset) {
|
|
self.offset_x = Offset::Relative(offset.x.clamp(0.0, 1.0));
|
|
self.offset_y = Offset::Relative(offset.y.clamp(0.0, 1.0));
|
|
}
|
|
|
|
/// Scroll to the provided [`AbsoluteOffset`].
|
|
pub fn scroll_to(&mut self, offset: AbsoluteOffset) {
|
|
self.offset_x = Offset::Absolute(offset.x.max(0.0));
|
|
self.offset_y = Offset::Absolute(offset.y.max(0.0));
|
|
}
|
|
|
|
/// Scroll by the provided [`AbsoluteOffset`].
|
|
pub fn scroll_by(
|
|
&mut self,
|
|
offset: AbsoluteOffset,
|
|
bounds: Rectangle,
|
|
content_bounds: Rectangle,
|
|
) {
|
|
self.scroll(Vector::new(offset.x, offset.y), bounds, content_bounds);
|
|
}
|
|
|
|
/// Unsnaps the current scroll position, if snapped, given the bounds of the
|
|
/// [`Scrollable`] and its contents.
|
|
pub fn unsnap(&mut self, bounds: Rectangle, content_bounds: Rectangle) {
|
|
self.offset_x = Offset::Absolute(
|
|
self.offset_x.absolute(bounds.width, content_bounds.width),
|
|
);
|
|
self.offset_y = Offset::Absolute(
|
|
self.offset_y.absolute(bounds.height, content_bounds.height),
|
|
);
|
|
}
|
|
|
|
/// Returns the scrolling translation of the [`State`], given a [`Direction`],
|
|
/// the bounds of the [`Scrollable`] and its contents.
|
|
fn translation(
|
|
&self,
|
|
direction: Direction,
|
|
bounds: Rectangle,
|
|
content_bounds: Rectangle,
|
|
) -> Vector {
|
|
Vector::new(
|
|
if let Some(horizontal) = direction.horizontal() {
|
|
self.offset_x.translation(
|
|
bounds.width,
|
|
content_bounds.width,
|
|
horizontal.alignment,
|
|
)
|
|
} else {
|
|
0.0
|
|
},
|
|
if let Some(vertical) = direction.vertical() {
|
|
self.offset_y.translation(
|
|
bounds.height,
|
|
content_bounds.height,
|
|
vertical.alignment,
|
|
)
|
|
} else {
|
|
0.0
|
|
},
|
|
)
|
|
}
|
|
|
|
/// Returns whether any scroller is currently grabbed or not.
|
|
pub fn scrollers_grabbed(&self) -> bool {
|
|
self.x_scroller_grabbed_at.is_some()
|
|
|| self.y_scroller_grabbed_at.is_some()
|
|
}
|
|
}
|
|
|
|
#[derive(Debug)]
|
|
/// State of both [`Scrollbar`]s.
|
|
struct Scrollbars {
|
|
y: Option<internals::Scrollbar>,
|
|
x: Option<internals::Scrollbar>,
|
|
}
|
|
|
|
impl Scrollbars {
|
|
/// Create y and/or x scrollbar(s) if content is overflowing the [`Scrollable`] bounds.
|
|
fn new(
|
|
state: &State,
|
|
direction: Direction,
|
|
bounds: Rectangle,
|
|
content_bounds: Rectangle,
|
|
) -> Self {
|
|
let translation = state.translation(direction, bounds, content_bounds);
|
|
|
|
let show_scrollbar_x = direction.horizontal().filter(|scrollbar| {
|
|
scrollbar.spacing.is_some() || content_bounds.width > bounds.width
|
|
});
|
|
|
|
let show_scrollbar_y = direction.vertical().filter(|scrollbar| {
|
|
scrollbar.spacing.is_some() || content_bounds.height > bounds.height
|
|
});
|
|
|
|
let y_scrollbar = if let Some(vertical) = show_scrollbar_y {
|
|
let Scrollbar {
|
|
width,
|
|
margin,
|
|
scroller_width,
|
|
..
|
|
} = *vertical;
|
|
|
|
// Adjust the height of the vertical scrollbar if the horizontal scrollbar
|
|
// is present
|
|
let x_scrollbar_height = show_scrollbar_x
|
|
.map_or(0.0, |h| h.width.max(h.scroller_width) + h.margin);
|
|
|
|
let total_scrollbar_width =
|
|
width.max(scroller_width) + 2.0 * margin;
|
|
|
|
// Total bounds of the scrollbar + margin + scroller width
|
|
let total_scrollbar_bounds = Rectangle {
|
|
x: bounds.x + bounds.width - total_scrollbar_width,
|
|
y: bounds.y,
|
|
width: total_scrollbar_width,
|
|
height: (bounds.height - x_scrollbar_height).max(0.0),
|
|
};
|
|
|
|
// Bounds of just the scrollbar
|
|
let scrollbar_bounds = Rectangle {
|
|
x: bounds.x + bounds.width
|
|
- total_scrollbar_width / 2.0
|
|
- width / 2.0,
|
|
y: bounds.y,
|
|
width,
|
|
height: (bounds.height - x_scrollbar_height).max(0.0),
|
|
};
|
|
|
|
let ratio = bounds.height / content_bounds.height;
|
|
|
|
let scroller = if ratio >= 1.0 {
|
|
None
|
|
} else {
|
|
// min height for easier grabbing with super tall content
|
|
let scroller_height =
|
|
(scrollbar_bounds.height * ratio).max(2.0);
|
|
let scroller_offset =
|
|
translation.y * ratio * scrollbar_bounds.height
|
|
/ bounds.height;
|
|
|
|
let scroller_bounds = Rectangle {
|
|
x: bounds.x + bounds.width
|
|
- total_scrollbar_width / 2.0
|
|
- scroller_width / 2.0,
|
|
y: (scrollbar_bounds.y + scroller_offset).max(0.0),
|
|
width: scroller_width,
|
|
height: scroller_height,
|
|
};
|
|
|
|
Some(internals::Scroller {
|
|
bounds: scroller_bounds,
|
|
})
|
|
};
|
|
|
|
Some(internals::Scrollbar {
|
|
total_bounds: total_scrollbar_bounds,
|
|
bounds: scrollbar_bounds,
|
|
scroller,
|
|
alignment: vertical.alignment,
|
|
disabled: content_bounds.height <= bounds.height,
|
|
})
|
|
} else {
|
|
None
|
|
};
|
|
|
|
let x_scrollbar = if let Some(horizontal) = show_scrollbar_x {
|
|
let Scrollbar {
|
|
width,
|
|
margin,
|
|
scroller_width,
|
|
..
|
|
} = *horizontal;
|
|
|
|
// Need to adjust the width of the horizontal scrollbar if the vertical scrollbar
|
|
// is present
|
|
let scrollbar_y_width = y_scrollbar
|
|
.map_or(0.0, |scrollbar| scrollbar.total_bounds.width);
|
|
|
|
let total_scrollbar_height =
|
|
width.max(scroller_width) + 2.0 * margin;
|
|
|
|
// Total bounds of the scrollbar + margin + scroller width
|
|
let total_scrollbar_bounds = Rectangle {
|
|
x: bounds.x,
|
|
y: bounds.y + bounds.height - total_scrollbar_height,
|
|
width: (bounds.width - scrollbar_y_width).max(0.0),
|
|
height: total_scrollbar_height,
|
|
};
|
|
|
|
// Bounds of just the scrollbar
|
|
let scrollbar_bounds = Rectangle {
|
|
x: bounds.x,
|
|
y: bounds.y + bounds.height
|
|
- total_scrollbar_height / 2.0
|
|
- width / 2.0,
|
|
width: (bounds.width - scrollbar_y_width).max(0.0),
|
|
height: width,
|
|
};
|
|
|
|
let ratio = bounds.width / content_bounds.width;
|
|
|
|
let scroller = if ratio >= 1.0 {
|
|
None
|
|
} else {
|
|
// min width for easier grabbing with extra wide content
|
|
let scroller_length = (scrollbar_bounds.width * ratio).max(2.0);
|
|
let scroller_offset =
|
|
translation.x * ratio * scrollbar_bounds.width
|
|
/ bounds.width;
|
|
|
|
let scroller_bounds = Rectangle {
|
|
x: (scrollbar_bounds.x + scroller_offset).max(0.0),
|
|
y: bounds.y + bounds.height
|
|
- total_scrollbar_height / 2.0
|
|
- scroller_width / 2.0,
|
|
width: scroller_length,
|
|
height: scroller_width,
|
|
};
|
|
|
|
Some(internals::Scroller {
|
|
bounds: scroller_bounds,
|
|
})
|
|
};
|
|
|
|
Some(internals::Scrollbar {
|
|
total_bounds: total_scrollbar_bounds,
|
|
bounds: scrollbar_bounds,
|
|
scroller,
|
|
alignment: horizontal.alignment,
|
|
disabled: content_bounds.width <= bounds.width,
|
|
})
|
|
} else {
|
|
None
|
|
};
|
|
|
|
Self {
|
|
y: y_scrollbar,
|
|
x: x_scrollbar,
|
|
}
|
|
}
|
|
|
|
fn is_mouse_over(&self, cursor: mouse::Cursor) -> (bool, bool) {
|
|
if let Some(cursor_position) = cursor.position() {
|
|
(
|
|
self.y
|
|
.as_ref()
|
|
.map(|scrollbar| scrollbar.is_mouse_over(cursor_position))
|
|
.unwrap_or(false),
|
|
self.x
|
|
.as_ref()
|
|
.map(|scrollbar| scrollbar.is_mouse_over(cursor_position))
|
|
.unwrap_or(false),
|
|
)
|
|
} else {
|
|
(false, false)
|
|
}
|
|
}
|
|
|
|
fn is_y_disabled(&self) -> bool {
|
|
self.y.map(|y| y.disabled).unwrap_or(false)
|
|
}
|
|
|
|
fn is_x_disabled(&self) -> bool {
|
|
self.x.map(|x| x.disabled).unwrap_or(false)
|
|
}
|
|
|
|
fn grab_y_scroller(&self, cursor_position: Point) -> Option<f32> {
|
|
let scrollbar = self.y?;
|
|
let scroller = scrollbar.scroller?;
|
|
|
|
if scrollbar.total_bounds.contains(cursor_position) {
|
|
Some(if scroller.bounds.contains(cursor_position) {
|
|
(cursor_position.y - scroller.bounds.y) / scroller.bounds.height
|
|
} else {
|
|
0.5
|
|
})
|
|
} else {
|
|
None
|
|
}
|
|
}
|
|
|
|
fn grab_x_scroller(&self, cursor_position: Point) -> Option<f32> {
|
|
let scrollbar = self.x?;
|
|
let scroller = scrollbar.scroller?;
|
|
|
|
if scrollbar.total_bounds.contains(cursor_position) {
|
|
Some(if scroller.bounds.contains(cursor_position) {
|
|
(cursor_position.x - scroller.bounds.x) / scroller.bounds.width
|
|
} else {
|
|
0.5
|
|
})
|
|
} else {
|
|
None
|
|
}
|
|
}
|
|
|
|
fn active(&self) -> bool {
|
|
self.y.is_some() || self.x.is_some()
|
|
}
|
|
}
|
|
|
|
pub(super) mod internals {
|
|
use crate::core::{Point, Rectangle};
|
|
|
|
use super::Anchor;
|
|
|
|
#[derive(Debug, Copy, Clone)]
|
|
pub struct Scrollbar {
|
|
pub total_bounds: Rectangle,
|
|
pub bounds: Rectangle,
|
|
pub scroller: Option<Scroller>,
|
|
pub alignment: Anchor,
|
|
pub disabled: bool,
|
|
}
|
|
|
|
impl Scrollbar {
|
|
/// Returns whether the mouse is over the scrollbar or not.
|
|
pub fn is_mouse_over(&self, cursor_position: Point) -> bool {
|
|
self.total_bounds.contains(cursor_position)
|
|
}
|
|
|
|
/// Returns the y-axis scrolled percentage from the cursor position.
|
|
pub fn scroll_percentage_y(
|
|
&self,
|
|
grabbed_at: f32,
|
|
cursor_position: Point,
|
|
) -> f32 {
|
|
if let Some(scroller) = self.scroller {
|
|
let percentage = (cursor_position.y
|
|
- self.bounds.y
|
|
- scroller.bounds.height * grabbed_at)
|
|
/ (self.bounds.height - scroller.bounds.height);
|
|
|
|
match self.alignment {
|
|
Anchor::Start => percentage,
|
|
Anchor::End => 1.0 - percentage,
|
|
}
|
|
} else {
|
|
0.0
|
|
}
|
|
}
|
|
|
|
/// Returns the x-axis scrolled percentage from the cursor position.
|
|
pub fn scroll_percentage_x(
|
|
&self,
|
|
grabbed_at: f32,
|
|
cursor_position: Point,
|
|
) -> f32 {
|
|
if let Some(scroller) = self.scroller {
|
|
let percentage = (cursor_position.x
|
|
- self.bounds.x
|
|
- scroller.bounds.width * grabbed_at)
|
|
/ (self.bounds.width - scroller.bounds.width);
|
|
|
|
match self.alignment {
|
|
Anchor::Start => percentage,
|
|
Anchor::End => 1.0 - percentage,
|
|
}
|
|
} else {
|
|
0.0
|
|
}
|
|
}
|
|
}
|
|
|
|
/// The handle of a [`Scrollbar`].
|
|
#[derive(Debug, Clone, Copy)]
|
|
pub struct Scroller {
|
|
/// The bounds of the [`Scroller`].
|
|
pub bounds: Rectangle,
|
|
}
|
|
}
|
|
|
|
/// The possible status of a [`Scrollable`].
|
|
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
|
|
pub enum Status {
|
|
/// The [`Scrollable`] can be interacted with.
|
|
Active {
|
|
/// Whether or not the horizontal scrollbar is disabled meaning the content isn't overflowing.
|
|
is_horizontal_scrollbar_disabled: bool,
|
|
/// Whether or not the vertical scrollbar is disabled meaning the content isn't overflowing.
|
|
is_vertical_scrollbar_disabled: bool,
|
|
},
|
|
/// The [`Scrollable`] is being hovered.
|
|
Hovered {
|
|
/// Indicates if the horizontal scrollbar is being hovered.
|
|
is_horizontal_scrollbar_hovered: bool,
|
|
/// Indicates if the vertical scrollbar is being hovered.
|
|
is_vertical_scrollbar_hovered: bool,
|
|
/// Whether or not the horizontal scrollbar is disabled meaning the content isn't overflowing.
|
|
is_horizontal_scrollbar_disabled: bool,
|
|
/// Whether or not the vertical scrollbar is disabled meaning the content isn't overflowing.
|
|
is_vertical_scrollbar_disabled: bool,
|
|
},
|
|
/// The [`Scrollable`] is being dragged.
|
|
Dragged {
|
|
/// Indicates if the horizontal scrollbar is being dragged.
|
|
is_horizontal_scrollbar_dragged: bool,
|
|
/// Indicates if the vertical scrollbar is being dragged.
|
|
is_vertical_scrollbar_dragged: bool,
|
|
/// Whether or not the horizontal scrollbar is disabled meaning the content isn't overflowing.
|
|
is_horizontal_scrollbar_disabled: bool,
|
|
/// Whether or not the vertical scrollbar is disabled meaning the content isn't overflowing.
|
|
is_vertical_scrollbar_disabled: bool,
|
|
},
|
|
}
|
|
|
|
/// The appearance of a scrollable.
|
|
#[derive(Debug, Clone, Copy, PartialEq)]
|
|
pub struct Style {
|
|
/// The [`container::Style`] of a scrollable.
|
|
pub container: container::Style,
|
|
/// The vertical [`Rail`] appearance.
|
|
pub vertical_rail: Rail,
|
|
/// The horizontal [`Rail`] appearance.
|
|
pub horizontal_rail: Rail,
|
|
/// The [`Background`] of the gap between a horizontal and vertical scrollbar.
|
|
pub gap: Option<Background>,
|
|
}
|
|
|
|
/// The appearance of the scrollbar of a scrollable.
|
|
#[derive(Debug, Clone, Copy, PartialEq)]
|
|
pub struct Rail {
|
|
/// The [`Background`] of a scrollbar.
|
|
pub background: Option<Background>,
|
|
/// The [`Border`] of a scrollbar.
|
|
pub border: Border,
|
|
/// The appearance of the [`Scroller`] of a scrollbar.
|
|
pub scroller: Scroller,
|
|
}
|
|
|
|
/// The appearance of the scroller of a scrollable.
|
|
#[derive(Debug, Clone, Copy, PartialEq)]
|
|
pub struct Scroller {
|
|
/// The [`Color`] of the scroller.
|
|
pub color: Color,
|
|
/// The [`Border`] of the scroller.
|
|
pub border: Border,
|
|
}
|
|
|
|
/// The theme catalog of a [`Scrollable`].
|
|
pub trait Catalog {
|
|
/// The item class of the [`Catalog`].
|
|
type Class<'a>;
|
|
|
|
/// The default class produced by the [`Catalog`].
|
|
fn default<'a>() -> Self::Class<'a>;
|
|
|
|
/// The [`Style`] of a class with the given status.
|
|
fn style(&self, class: &Self::Class<'_>, status: Status) -> Style;
|
|
}
|
|
|
|
/// A styling function for a [`Scrollable`].
|
|
pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Style + 'a>;
|
|
|
|
impl Catalog for Theme {
|
|
type Class<'a> = StyleFn<'a, Self>;
|
|
|
|
fn default<'a>() -> Self::Class<'a> {
|
|
Box::new(default)
|
|
}
|
|
|
|
fn style(&self, class: &Self::Class<'_>, status: Status) -> Style {
|
|
class(self, status)
|
|
}
|
|
}
|
|
|
|
/// The default style of a [`Scrollable`].
|
|
pub fn default(theme: &Theme, status: Status) -> Style {
|
|
let palette = theme.extended_palette();
|
|
|
|
let scrollbar = Rail {
|
|
background: Some(palette.background.weak.color.into()),
|
|
border: border::rounded(2),
|
|
scroller: Scroller {
|
|
color: palette.background.strong.color,
|
|
border: border::rounded(2),
|
|
},
|
|
};
|
|
|
|
match status {
|
|
Status::Active { .. } => Style {
|
|
container: container::Style::default(),
|
|
vertical_rail: scrollbar,
|
|
horizontal_rail: scrollbar,
|
|
gap: None,
|
|
},
|
|
Status::Hovered {
|
|
is_horizontal_scrollbar_hovered,
|
|
is_vertical_scrollbar_hovered,
|
|
..
|
|
} => {
|
|
let hovered_scrollbar = Rail {
|
|
scroller: Scroller {
|
|
color: palette.primary.strong.color,
|
|
..scrollbar.scroller
|
|
},
|
|
..scrollbar
|
|
};
|
|
|
|
Style {
|
|
container: container::Style::default(),
|
|
vertical_rail: if is_vertical_scrollbar_hovered {
|
|
hovered_scrollbar
|
|
} else {
|
|
scrollbar
|
|
},
|
|
horizontal_rail: if is_horizontal_scrollbar_hovered {
|
|
hovered_scrollbar
|
|
} else {
|
|
scrollbar
|
|
},
|
|
gap: None,
|
|
}
|
|
}
|
|
Status::Dragged {
|
|
is_horizontal_scrollbar_dragged,
|
|
is_vertical_scrollbar_dragged,
|
|
..
|
|
} => {
|
|
let dragged_scrollbar = Rail {
|
|
scroller: Scroller {
|
|
color: palette.primary.base.color,
|
|
..scrollbar.scroller
|
|
},
|
|
..scrollbar
|
|
};
|
|
|
|
Style {
|
|
container: container::Style::default(),
|
|
vertical_rail: if is_vertical_scrollbar_dragged {
|
|
dragged_scrollbar
|
|
} else {
|
|
scrollbar
|
|
},
|
|
horizontal_rail: if is_horizontal_scrollbar_dragged {
|
|
dragged_scrollbar
|
|
} else {
|
|
scrollbar
|
|
},
|
|
gap: None,
|
|
}
|
|
}
|
|
}
|
|
}
|