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mod element;
mod group;
pub mod menu;
pub use element::Element;
pub use group::Group;
pub use menu::Menu;
use crate::event::{self, Event};
use crate::layout;
use crate::mouse;
use crate::renderer;
use crate::widget;
use crate::widget::Tree;
use crate::{Clipboard, Layout, Point, Rectangle, Shell, Size};
pub trait Overlay<Message, Renderer>
where
Renderer: crate::Renderer,
{
fn layout(
&self,
renderer: &Renderer,
bounds: Size,
position: Point,
) -> layout::Node;
fn draw(
&self,
renderer: &mut Renderer,
theme: &Renderer::Theme,
style: &renderer::Style,
layout: Layout<'_>,
cursor_position: Point,
);
fn operate(
&mut self,
_layout: Layout<'_>,
_renderer: &Renderer,
_operation: &mut dyn widget::Operation<Message>,
) {
}
fn on_event(
&mut self,
_event: Event,
_layout: Layout<'_>,
_cursor_position: Point,
_renderer: &Renderer,
_clipboard: &mut dyn Clipboard,
_shell: &mut Shell<'_, Message>,
) -> event::Status {
event::Status::Ignored
}
fn mouse_interaction(
&self,
_layout: Layout<'_>,
_cursor_position: Point,
_viewport: &Rectangle,
_renderer: &Renderer,
) -> mouse::Interaction {
mouse::Interaction::Idle
}
fn is_over(&self, layout: Layout<'_>, cursor_position: Point) -> bool {
layout.bounds().contains(cursor_position)
}
}
pub fn from_children<'a, Message, Renderer>(
children: &'a mut [crate::Element<'_, Message, Renderer>],
tree: &'a mut Tree,
layout: Layout<'_>,
renderer: &Renderer,
) -> Option<Element<'a, Message, Renderer>>
where
Renderer: crate::Renderer,
{
let children = children
.iter_mut()
.zip(&mut tree.children)
.zip(layout.children())
.filter_map(|((child, state), layout)| {
child.as_widget_mut().overlay(state, layout, renderer)
})
.collect::<Vec<_>>();
(!children.is_empty()).then(|| Group::with_children(children).overlay())
}