diff options
Diffstat (limited to 'widget/src/lazy.rs')
| -rw-r--r-- | widget/src/lazy.rs | 87 |
1 files changed, 41 insertions, 46 deletions
diff --git a/widget/src/lazy.rs b/widget/src/lazy.rs index b08ed8cb..da287f06 100644 --- a/widget/src/lazy.rs +++ b/widget/src/lazy.rs @@ -20,12 +20,14 @@ use crate::core::Element; use crate::core::{ self, Clipboard, Hasher, Length, Point, Rectangle, Shell, Size, }; +use crate::runtime::overlay::Nested; use ouroboros::self_referencing; use std::cell::RefCell; use std::hash::{Hash, Hasher as H}; use std::rc::Rc; +/// A widget that only rebuilds its contents when necessary. #[allow(missing_debug_implementations)] pub struct Lazy<'a, Message, Renderer, Dependency, View> { dependency: Dependency, @@ -41,6 +43,8 @@ where Dependency: Hash + 'a, View: Into<Element<'static, Message, Renderer>>, { + /// Creates a new [`Lazy`] widget with the given data `Dependency` and a + /// closure that can turn this data into a widget tree. pub fn new( dependency: Dependency, view: impl Fn(&Dependency) -> View + 'a, @@ -178,7 +182,7 @@ where tree: &mut Tree, event: Event, layout: Layout<'_>, - cursor_position: Point, + cursor: mouse::Cursor, renderer: &Renderer, clipboard: &mut dyn Clipboard, shell: &mut Shell<'_, Message>, @@ -188,7 +192,7 @@ where &mut tree.children[0], event, layout, - cursor_position, + cursor, renderer, clipboard, shell, @@ -200,7 +204,7 @@ where &self, tree: &Tree, layout: Layout<'_>, - cursor_position: Point, + cursor: mouse::Cursor, viewport: &Rectangle, renderer: &Renderer, ) -> mouse::Interaction { @@ -208,7 +212,7 @@ where element.as_widget().mouse_interaction( &tree.children[0], layout, - cursor_position, + cursor, viewport, renderer, ) @@ -222,7 +226,7 @@ where theme: &Renderer::Theme, style: &renderer::Style, layout: Layout<'_>, - cursor_position: Point, + cursor: mouse::Cursor, viewport: &Rectangle, ) { self.with_element(|element| { @@ -232,7 +236,7 @@ where theme, style, layout, - cursor_position, + cursor, viewport, ) }) @@ -257,14 +261,17 @@ where .unwrap(), tree: &mut tree.children[0], overlay_builder: |element, tree| { - element.as_widget_mut().overlay(tree, layout, renderer) + element + .as_widget_mut() + .overlay(tree, layout, renderer) + .map(|overlay| RefCell::new(Nested::new(overlay))) }, } .build(), )); - let has_overlay = overlay - .with_overlay_maybe(|overlay| overlay::Element::position(overlay)); + let has_overlay = + overlay.with_overlay_maybe(|overlay| overlay.position()); has_overlay .map(|position| overlay::Element::new(position, Box::new(overlay))) @@ -272,18 +279,14 @@ where } #[self_referencing] -struct Inner<'a, Message, Renderer> -where - Message: 'a, - Renderer: 'a, -{ +struct Inner<'a, Message: 'a, Renderer: 'a> { cell: Rc<RefCell<Option<Element<'static, Message, Renderer>>>>, element: Element<'static, Message, Renderer>, tree: &'a mut Tree, #[borrows(mut element, mut tree)] - #[covariant] - overlay: Option<overlay::Element<'this, Message, Renderer>>, + #[not_covariant] + overlay: Option<RefCell<Nested<'this, Message, Renderer>>>, } struct Overlay<'a, Message, Renderer>(Option<Inner<'a, Message, Renderer>>); @@ -298,19 +301,20 @@ impl<'a, Message, Renderer> Drop for Overlay<'a, Message, Renderer> { impl<'a, Message, Renderer> Overlay<'a, Message, Renderer> { fn with_overlay_maybe<T>( &self, - f: impl FnOnce(&overlay::Element<'_, Message, Renderer>) -> T, + f: impl FnOnce(&mut Nested<'_, Message, Renderer>) -> T, ) -> Option<T> { - self.0.as_ref().unwrap().borrow_overlay().as_ref().map(f) + self.0.as_ref().unwrap().with_overlay(|overlay| { + overlay.as_ref().map(|nested| (f)(&mut nested.borrow_mut())) + }) } fn with_overlay_mut_maybe<T>( &mut self, - f: impl FnOnce(&mut overlay::Element<'_, Message, Renderer>) -> T, + f: impl FnOnce(&mut Nested<'_, Message, Renderer>) -> T, ) -> Option<T> { - self.0 - .as_mut() - .unwrap() - .with_overlay_mut(|overlay| overlay.as_mut().map(f)) + self.0.as_mut().unwrap().with_overlay_mut(|overlay| { + overlay.as_mut().map(|nested| (f)(nested.get_mut())) + }) } } @@ -326,9 +330,7 @@ where position: Point, ) -> layout::Node { self.with_overlay_maybe(|overlay| { - let translation = position - overlay.position(); - - overlay.layout(renderer, bounds, translation) + overlay.layout(renderer, bounds, position) }) .unwrap_or_default() } @@ -339,27 +341,22 @@ where theme: &Renderer::Theme, style: &renderer::Style, layout: Layout<'_>, - cursor_position: Point, + cursor: mouse::Cursor, ) { let _ = self.with_overlay_maybe(|overlay| { - overlay.draw(renderer, theme, style, layout, cursor_position); + overlay.draw(renderer, theme, style, layout, cursor); }); } fn mouse_interaction( &self, layout: Layout<'_>, - cursor_position: Point, + cursor: mouse::Cursor, viewport: &Rectangle, renderer: &Renderer, ) -> mouse::Interaction { self.with_overlay_maybe(|overlay| { - overlay.mouse_interaction( - layout, - cursor_position, - viewport, - renderer, - ) + overlay.mouse_interaction(layout, cursor, viewport, renderer) }) .unwrap_or_default() } @@ -368,27 +365,25 @@ where &mut self, event: Event, layout: Layout<'_>, - cursor_position: Point, + cursor: mouse::Cursor, 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, - ) + overlay.on_event(event, layout, cursor, renderer, clipboard, shell) }) .unwrap_or(event::Status::Ignored) } - fn is_over(&self, layout: Layout<'_>, cursor_position: Point) -> bool { + fn is_over( + &self, + layout: Layout<'_>, + renderer: &Renderer, + cursor_position: Point, + ) -> bool { self.with_overlay_maybe(|overlay| { - overlay.is_over(layout, cursor_position) + overlay.is_over(layout, renderer, cursor_position) }) .unwrap_or_default() } |