diff options
Diffstat (limited to 'lazy')
| -rw-r--r-- | lazy/Cargo.toml | 11 | ||||
| -rw-r--r-- | lazy/src/component.rs | 186 | ||||
| -rw-r--r-- | lazy/src/lib.rs | 3 |
3 files changed, 200 insertions, 0 deletions
diff --git a/lazy/Cargo.toml b/lazy/Cargo.toml new file mode 100644 index 00000000..b840de50 --- /dev/null +++ b/lazy/Cargo.toml @@ -0,0 +1,11 @@ +[package] +name = "iced_lazy" +version = "0.1.0" +edition = "2021" + +[dependencies] +ouroboros = "0.13" + +[dependencies.iced_native] +version = "0.4" +path = "../native" diff --git a/lazy/src/component.rs b/lazy/src/component.rs new file mode 100644 index 00000000..aa5b847e --- /dev/null +++ b/lazy/src/component.rs @@ -0,0 +1,186 @@ +use iced_native::event; +use iced_native::layout::{self, Layout}; +use iced_native::mouse; +use iced_native::overlay; +use iced_native::renderer; +use iced_native::{ + Clipboard, Element, Hasher, Length, Point, Rectangle, Shell, Widget, +}; + +use ouroboros::self_referencing; +use std::marker::PhantomData; + +pub fn view<'a, C, Message, Renderer>( + component: C, +) -> Element<'a, Message, Renderer> +where + C: Component<Message, Renderer> + 'a, + Message: 'a, + Renderer: iced_native::Renderer + 'a, +{ + Element::new(Instance { + state: Some( + StateBuilder { + component: Box::new(component), + cache_builder: |state| Cache { + element: state.view(), + message: PhantomData, + }, + } + .build(), + ), + }) +} + +pub trait Component<Message, Renderer> { + type Event; + + fn update(&mut self, event: Self::Event) -> Option<Message>; + + fn view(&mut self) -> Element<Self::Event, Renderer>; +} + +struct Instance<'a, Message, Renderer, Event> { + state: Option<State<'a, Message, Renderer, Event>>, +} + +#[self_referencing] +struct State<'a, Message: 'a, Renderer: 'a, Event: 'a> { + component: Box<dyn Component<Message, Renderer, Event = Event> + 'a>, + + #[borrows(mut component)] + #[covariant] + cache: Cache<'this, Message, Renderer, Event>, +} + +struct Cache<'a, Message, Renderer, Event> { + element: Element<'a, Event, Renderer>, + message: PhantomData<Message>, +} + +impl<'a, Message, Renderer, Event> Widget<Message, Renderer> + for Instance<'a, Message, Renderer, Event> +where + Renderer: iced_native::Renderer, +{ + fn width(&self) -> Length { + self.state.as_ref().unwrap().borrow_cache().element.width() + } + + fn height(&self) -> Length { + self.state.as_ref().unwrap().borrow_cache().element.width() + } + + fn layout( + &self, + renderer: &Renderer, + limits: &layout::Limits, + ) -> layout::Node { + self.state + .as_ref() + .unwrap() + .borrow_cache() + .element + .layout(renderer, limits) + } + + 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 { + let mut local_messages = Vec::new(); + let mut local_shell = Shell::new(&mut local_messages); + + let event_status = + self.state.as_mut().unwrap().with_cache_mut(|cache| { + cache.element.on_event( + event, + layout, + cursor_position, + renderer, + clipboard, + &mut local_shell, + ) + }); + + if !local_messages.is_empty() { + let mut component = + self.state.take().unwrap().into_heads().component; + + for message in local_messages + .into_iter() + .filter_map(|message| component.update(message)) + { + shell.publish(message); + } + + self.state = Some( + StateBuilder { + component, + cache_builder: |state| Cache { + element: state.view(), + message: PhantomData, + }, + } + .build(), + ); + + shell.invalidate_layout(); + } + + event_status + } + + fn draw( + &self, + renderer: &mut Renderer, + style: &renderer::Style, + layout: Layout<'_>, + cursor_position: Point, + viewport: &Rectangle, + ) { + self.state.as_ref().unwrap().borrow_cache().element.draw( + renderer, + style, + layout, + cursor_position, + viewport, + ) + } + + fn hash_layout(&self, state: &mut Hasher) { + self.state + .as_ref() + .unwrap() + .borrow_cache() + .element + .hash_layout(state) + } + + fn mouse_interaction( + &self, + layout: Layout<'_>, + cursor_position: Point, + viewport: &Rectangle, + ) -> mouse::Interaction { + self.state + .as_ref() + .unwrap() + .borrow_cache() + .element + .mouse_interaction(layout, cursor_position, viewport) + } + + fn overlay( + &mut self, + _layout: Layout<'_>, + ) -> Option<overlay::Element<'_, Message, Renderer>> { + // TODO: Rethink overlay composability + None + } +} diff --git a/lazy/src/lib.rs b/lazy/src/lib.rs new file mode 100644 index 00000000..42e5f587 --- /dev/null +++ b/lazy/src/lib.rs @@ -0,0 +1,3 @@ +pub mod component; + +pub use component::Component; |