From b50e208f31e51c2d947aeaf9fea8a9f287f26aa1 Mon Sep 17 00:00:00 2001 From: Héctor Ramón Jiménez Date: Mon, 7 Mar 2022 18:04:13 +0700 Subject: Implement `pure::Responsive` in `iced_lazy` --- lazy/src/pure/responsive.rs | 365 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 365 insertions(+) create mode 100644 lazy/src/pure/responsive.rs (limited to 'lazy/src/pure/responsive.rs') diff --git a/lazy/src/pure/responsive.rs b/lazy/src/pure/responsive.rs new file mode 100644 index 00000000..2b77873f --- /dev/null +++ b/lazy/src/pure/responsive.rs @@ -0,0 +1,365 @@ +use iced_native::event; +use iced_native::layout::{self, Layout}; +use iced_native::mouse; +use iced_native::renderer; +use iced_native::{Clipboard, Length, Point, Rectangle, Shell, Size}; +use iced_pure::overlay; +use iced_pure::widget::horizontal_space; +use iced_pure::widget::tree::{self, Tree}; +use iced_pure::{Element, Widget}; + +use ouroboros::self_referencing; +use std::cell::{Ref, RefCell, RefMut}; +use std::marker::PhantomData; +use std::ops::Deref; + +/// A widget that is aware of its dimensions. +/// +/// A [`Responsive`] widget will always try to fill all the available space of +/// its parent. +#[allow(missing_debug_implementations)] +pub struct Responsive<'a, Message, Renderer> { + view: Box Element<'a, Message, Renderer> + 'a>, + content: RefCell>, +} + +impl<'a, Message, Renderer> Responsive<'a, Message, Renderer> +where + Renderer: iced_native::Renderer, +{ + /// Creates a new [`Responsive`] widget with a closure that produces its + /// contents. + /// + /// The `view` closure will be provided with the current [`Size`] of + /// the [`Responsive`] widget and, therefore, can be used to build the + /// contents of the widget in a responsive way. + pub fn new( + view: impl Fn(Size) -> Element<'a, Message, Renderer> + 'a, + ) -> Self { + Self { + view: Box::new(view), + content: RefCell::new(Content { + size: Size::ZERO, + layout: layout::Node::new(Size::ZERO), + element: Element::new(horizontal_space(Length::Units(0))), + }), + } + } +} + +struct Content<'a, Message, Renderer> { + size: Size, + layout: layout::Node, + element: Element<'a, Message, Renderer>, +} + +impl<'a, Message, Renderer> Content<'a, Message, Renderer> { + fn update( + &mut self, + tree: &mut Tree, + renderer: &Renderer, + new_size: Size, + view: &dyn Fn(Size) -> Element<'a, Message, Renderer>, + ) { + if self.size == new_size { + return; + } + + self.element = view(new_size); + self.size = new_size; + self.layout = self + .element + .as_widget() + .layout(renderer, &layout::Limits::new(Size::ZERO, self.size)); + + tree.diff(&self.element); + } + + fn resolve( + &mut self, + tree: &mut Tree, + renderer: R, + layout: Layout<'_>, + view: &dyn Fn(Size) -> Element<'a, Message, Renderer>, + f: impl FnOnce( + &mut Tree, + R, + Layout<'_>, + &mut Element<'a, Message, Renderer>, + ) -> T, + ) -> T + where + R: Deref, + { + self.update(tree, renderer.deref(), layout.bounds().size(), view); + + let content_layout = Layout::with_offset( + layout.position() - Point::ORIGIN, + &self.layout, + ); + + f(tree, renderer, content_layout, &mut self.element) + } +} + +struct State { + tree: RefCell, +} + +impl<'a, Message, Renderer> Widget + for Responsive<'a, Message, Renderer> +where + Renderer: iced_native::Renderer, +{ + fn tag(&self) -> tree::Tag { + tree::Tag::of::() + } + + fn state(&self) -> tree::State { + tree::State::new(State { + tree: RefCell::new(Tree::empty()), + }) + } + + fn width(&self) -> Length { + Length::Fill + } + + fn height(&self) -> Length { + Length::Fill + } + + fn layout( + &self, + _renderer: &Renderer, + limits: &layout::Limits, + ) -> layout::Node { + layout::Node::new(limits.max()) + } + + fn on_event( + &mut self, + tree: &mut Tree, + event: iced_native::Event, + layout: Layout<'_>, + cursor_position: Point, + renderer: &Renderer, + clipboard: &mut dyn Clipboard, + shell: &mut Shell<'_, Message>, + ) -> event::Status { + let state = tree.state.downcast_mut::(); + let mut content = self.content.borrow_mut(); + + content.resolve( + &mut state.tree.borrow_mut(), + renderer, + layout, + &self.view, + |tree, renderer, layout, element| { + element.as_widget_mut().on_event( + tree, + event, + layout, + cursor_position, + renderer, + clipboard, + shell, + ) + }, + ) + } + + fn draw( + &self, + tree: &Tree, + renderer: &mut Renderer, + style: &renderer::Style, + layout: Layout<'_>, + cursor_position: Point, + viewport: &Rectangle, + ) { + let state = tree.state.downcast_ref::(); + let mut content = self.content.borrow_mut(); + + content.resolve( + &mut state.tree.borrow_mut(), + renderer, + layout, + &self.view, + |tree, renderer, layout, element| { + element.as_widget().draw( + tree, + renderer, + style, + layout, + cursor_position, + viewport, + ) + }, + ) + } + + fn mouse_interaction( + &self, + tree: &Tree, + layout: Layout<'_>, + cursor_position: Point, + viewport: &Rectangle, + renderer: &Renderer, + ) -> mouse::Interaction { + let state = tree.state.downcast_ref::(); + let mut content = self.content.borrow_mut(); + + content.resolve( + &mut state.tree.borrow_mut(), + renderer, + layout, + &self.view, + |tree, renderer, layout, element| { + element.as_widget().mouse_interaction( + tree, + layout, + cursor_position, + viewport, + renderer, + ) + }, + ) + } + + fn overlay<'b>( + &'b self, + tree: &'b mut Tree, + layout: Layout<'_>, + renderer: &Renderer, + ) -> Option> { + let state = tree.state.downcast_ref::(); + + let overlay = OverlayBuilder { + content: self.content.borrow(), + tree: state.tree.borrow_mut(), + types: PhantomData, + overlay_builder: |content, tree| { + content.element.as_widget().overlay(tree, layout, renderer) + }, + } + .build(); + + let has_overlay = overlay.with_overlay(|overlay| { + overlay.as_ref().map(overlay::Element::position) + }); + + has_overlay + .map(|position| overlay::Element::new(position, Box::new(overlay))) + } +} + +impl<'a, Message, Renderer> From> + for Element<'a, Message, Renderer> +where + Renderer: iced_native::Renderer + 'a, + Message: 'a, +{ + fn from(responsive: Responsive<'a, Message, Renderer>) -> Self { + Self::new(responsive) + } +} + +#[self_referencing] +struct Overlay<'a, 'b, Message, Renderer> { + content: Ref<'a, Content<'b, Message, Renderer>>, + tree: RefMut<'a, Tree>, + types: PhantomData, + + #[borrows(content, mut tree)] + #[covariant] + overlay: Option>, +} + +impl<'a, 'b, Message, Renderer> Overlay<'a, 'b, Message, Renderer> { + fn with_overlay_maybe( + &self, + f: impl FnOnce(&overlay::Element<'_, Message, Renderer>) -> T, + ) -> Option { + self.borrow_overlay().as_ref().map(f) + } + + fn with_overlay_mut_maybe( + &mut self, + f: impl FnOnce(&mut overlay::Element<'_, Message, Renderer>) -> T, + ) -> Option { + self.with_overlay_mut(|overlay| overlay.as_mut().map(f)) + } +} + +impl<'a, 'b, Message, Renderer> overlay::Overlay + for Overlay<'a, 'b, Message, Renderer> +where + Renderer: iced_native::Renderer, +{ + fn layout( + &self, + renderer: &Renderer, + bounds: Size, + position: Point, + ) -> layout::Node { + self.with_overlay_maybe(|overlay| { + let vector = position - overlay.position(); + + overlay.layout(renderer, bounds).translate(vector) + }) + .unwrap_or_default() + } + + fn draw( + &self, + renderer: &mut Renderer, + style: &renderer::Style, + layout: Layout<'_>, + cursor_position: Point, + ) { + self.with_overlay_maybe(|overlay| { + overlay.draw(renderer, style, layout, cursor_position); + }); + } + + fn mouse_interaction( + &self, + layout: Layout<'_>, + cursor_position: Point, + viewport: &Rectangle, + renderer: &Renderer, + ) -> mouse::Interaction { + self.with_overlay_maybe(|overlay| { + overlay.mouse_interaction( + layout, + cursor_position, + viewport, + renderer, + ) + }) + .unwrap_or_default() + } + + fn on_event( + &mut self, + event: iced_native::Event, + layout: Layout<'_>, + cursor_position: Point, + renderer: &Renderer, + clipboard: &mut dyn Clipboard, + shell: &mut Shell<'_, Message>, + ) -> event::Status { + self.with_overlay_mut_maybe(|overlay| { + overlay.on_event( + event, + layout, + cursor_position, + renderer, + clipboard, + shell, + ) + }) + .unwrap_or_else(|| iced_native::event::Status::Ignored) + } +} -- cgit