Use+as 只要实现不要特型

#[allow(unused_imports)]
pub mod prelude {
      pub use super::{
        interaction::InteractionPalette,
        palette as ui_palette,
        widgets::{Containers as _, Widgets as _},
    };
}

pub trait Containers {
    /// Spawns a root node that covers the full screen
    /// and centers its content horizontally and vertically.
    fn ui_root(&mut self) -> EntityCommands;
}

impl Containers for Commands<'_, '_> {
    fn ui_root(&mut self) -> EntityCommands {
        self.spawn((
            Name::new("UI Root"),
            Node {
                width: Percent(100.0),
                height: Percent(100.0),
                justify_content: JustifyContent::Center,
                align_items: AlignItems::Center,
                flex_direction: FlexDirection::Column,
                row_gap: Px(10.0),
                position_type: PositionType::Absolute,
                ..default()
            },
        ))
    }
}