diff options
Diffstat (limited to 'lazy/src/component.rs')
| -rw-r--r-- | lazy/src/component.rs | 88 |
1 files changed, 58 insertions, 30 deletions
diff --git a/lazy/src/component.rs b/lazy/src/component.rs index fd3f6ff7..2b729045 100644 --- a/lazy/src/component.rs +++ b/lazy/src/component.rs @@ -1,3 +1,6 @@ +//! Build and reuse custom widgets using The Elm Architecture. +use crate::{Cache, CacheBuilder}; + use iced_native::event; use iced_native::layout::{self, Layout}; use iced_native::mouse; @@ -12,6 +15,35 @@ use std::cell::RefCell; use std::hash::Hash; use std::marker::PhantomData; +/// A reusable, custom widget that uses The Elm Architecture. +/// +/// A [`Component`] allows you to implement custom widgets as if they were +/// `iced` applications with encapsulated state. +/// +/// In other words, a [`Component`] allows you to turn `iced` applications into +/// custom widgets and embed them without cumbersome wiring. +/// +/// A [`Component`] produces widgets that may fire an [`Event`](Component::Event) +/// and update the internal state of the [`Component`]. +/// +/// Additionally, a [`Component`] is capable of producing a `Message` to notify +/// the parent application of any relevant interactions. +pub trait Component<Message, Renderer> { + /// The type of event this [`Component`] handles internally. + type Event; + + /// Processes an [`Event`](Component::Event) and updates the [`Component`] state accordingly. + /// + /// It can produce a `Message` for the parent application. + fn update(&mut self, event: Self::Event) -> Option<Message>; + + /// Produces the widgets of the [`Component`], which may trigger an [`Event`](Component::Event) + /// on user interaction. + fn view(&mut self) -> Element<Self::Event, Renderer>; +} + +/// Turns an implementor of [`Component`] into an [`Element`] that can be +/// embedded in any application. pub fn view<'a, C, Message, Renderer>( component: C, ) -> Element<'a, Message, Renderer> @@ -24,11 +56,11 @@ where state: RefCell::new(Some( StateBuilder { component: Box::new(component), + message: PhantomData, cache_builder: |state| { Some( CacheBuilder { element: state.view(), - message: PhantomData, overlay_builder: |_| None, } .build(), @@ -40,14 +72,6 @@ where }) } -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: RefCell<Option<State<'a, Message, Renderer, Event>>>, } @@ -55,20 +79,11 @@ struct Instance<'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: Option<Cache<'this, Message, Renderer, Event>>, -} - -#[self_referencing] -struct Cache<'a, Message, Renderer: 'a, Event: 'a> { - element: Element<'a, Event, Renderer>, message: PhantomData<Message>, - #[borrows(mut element)] + #[borrows(mut component)] #[covariant] - overlay: Option<overlay::Element<'this, Event, Renderer>>, + cache: Option<Cache<'this, Event, Renderer>>, } impl<'a, Message, Renderer, Event> Instance<'a, Message, Renderer, Event> { @@ -94,7 +109,6 @@ impl<'a, Message, Renderer, Event> Instance<'a, Message, Renderer, Event> { *cache = Some( CacheBuilder { element, - message: PhantomData, overlay_builder: |_| None, } .build(), @@ -149,7 +163,7 @@ where ) }); - local_shell.with_invalid_layout(|| shell.invalidate_layout()); + local_shell.revalidate_layout(|| shell.invalidate_layout()); if !local_messages.is_empty() { let mut component = self @@ -170,11 +184,11 @@ where *self.state.borrow_mut() = Some( StateBuilder { component, + message: PhantomData, cache_builder: |state| { Some( CacheBuilder { element: state.view(), - message: PhantomData, overlay_builder: |_| None, } .build(), @@ -214,15 +228,22 @@ where layout: Layout<'_>, cursor_position: Point, viewport: &Rectangle, + renderer: &Renderer, ) -> mouse::Interaction { self.with_element(|element| { - element.mouse_interaction(layout, cursor_position, viewport) + element.mouse_interaction( + layout, + cursor_position, + viewport, + renderer, + ) }) } fn overlay( &mut self, layout: Layout<'_>, + renderer: &Renderer, ) -> Option<overlay::Element<'_, Message, Renderer>> { let has_overlay = self .state @@ -235,8 +256,9 @@ where *cache = Some( CacheBuilder { element, - message: PhantomData, - overlay_builder: |element| element.overlay(layout), + overlay_builder: |element| { + element.overlay(layout, renderer) + }, } .build(), ); @@ -331,9 +353,15 @@ where layout: Layout<'_>, cursor_position: Point, viewport: &Rectangle, + renderer: &Renderer, ) -> mouse::Interaction { self.with_overlay_maybe(|overlay| { - overlay.mouse_interaction(layout, cursor_position, viewport) + overlay.mouse_interaction( + layout, + cursor_position, + viewport, + renderer, + ) }) .unwrap_or_default() } @@ -375,7 +403,7 @@ where }) .unwrap_or_else(|| iced_native::event::Status::Ignored); - local_shell.with_invalid_layout(|| shell.invalidate_layout()); + local_shell.revalidate_layout(|| shell.invalidate_layout()); if !local_messages.is_empty() { let mut component = @@ -391,13 +419,13 @@ where self.instance.state = RefCell::new(Some( StateBuilder { component, + message: PhantomData, cache_builder: |state| { Some( CacheBuilder { element: state.view(), - message: PhantomData, overlay_builder: |element| { - element.overlay(layout) + element.overlay(layout, renderer) }, } .build(), |