showbits/showbits-common/src/widget.rs

53 lines
1.2 KiB
Rust

use taffy::{AvailableSpace, Layout, Size};
use crate::{Node, View};
pub trait Widget<C> {
/// Used for the measure function in
/// [`taffy::TaffyTree::compute_layout_with_measure`].
#[allow(unused_variables)]
fn size(
&mut self,
ctx: &mut C,
known: Size<Option<f32>>,
available: Size<AvailableSpace>,
) -> Size<f32> {
Size::ZERO
}
/// Called before all children are drawn.
///
/// Prefer this over [`Self::draw_above`] when implementing a leaf widget.
#[allow(unused_variables)]
fn draw_below(
&mut self,
ctx: &mut C,
view: &mut View<'_>,
layout: &Layout,
) -> anyhow::Result<()> {
Ok(())
}
/// Called after all children are drawn.
#[allow(unused_variables)]
fn draw_above(
&mut self,
ctx: &mut C,
view: &mut View<'_>,
layout: &Layout,
) -> anyhow::Result<()> {
Ok(())
}
}
pub type BoxedWidget<C> = Box<dyn Widget<C>>;
pub trait WidgetExt<C> {
fn node(self) -> Node<C>;
}
impl<C, W: Widget<C> + 'static> WidgetExt<C> for W {
fn node(self) -> Node<C> {
Node::empty().widget(self)
}
}