RAUI retained mode experiments

retained_mode.rs

use raui::prelude::*;
use raui_quick_start::RauiQuickStartBuilder;
use std::any::Any;

#[derive(Default)]
struct AppView {
    pub icons: View<ListView<IconView>>,
}

impl ViewState for AppView {
    fn on_render(&self, context: WidgetContext) -> WidgetNode {
        self.icons.component().key(context.key).into()
    }

    fn as_any(&self) -> &dyn Any {
        self
    }

    fn as_any_mut(&mut self) -> &mut dyn Any {
        self
    }
}

struct ListView<T: ViewState> {
    pub items: Vec<View<T>>,
}

impl<T: ViewState> Default for ListView<T> {
    fn default() -> Self {
        Self {
            items: Default::default(),
        }
    }
}

impl<T: ViewState> ViewState for ListView<T> {
    fn on_render(&self, context: WidgetContext) -> WidgetNode {
        make_widget!(vertical_box)
            .key(context.key)
            .listed_slots(self.items.iter().map(|item| item.component()))
            .into()
    }

    fn as_any(&self) -> &dyn Any {
        self
    }

    fn as_any_mut(&mut self) -> &mut dyn Any {
        self
    }
}

struct IconView {
    pub color: Color,
    pub size: Scalar,
}

impl ViewState for IconView {
    fn on_render(&self, context: WidgetContext) -> WidgetNode {
        make_widget!(image_box)
            .key(context.key)
            .with_props(ImageBoxProps {
                width: ImageBoxSizeValue::Exact(self.size),
                height: ImageBoxSizeValue::Exact(self.size),
                material: ImageBoxMaterial::Color(ImageBoxColor {
                    color: self.color,
                    ..Default::default()
                }),
                ..Default::default()
            })
            .into()
    }

    fn as_any(&self) -> &dyn Any {
        self
    }

    fn as_any_mut(&mut self) -> &mut dyn Any {
        self
    }
}

fn main() {
    let app = View::new(AppView {
        icons: View::new(ListView {
            items: vec![
                View::new(IconView {
                    color: Color {
                        r: 1.0,
                        g: 0.25,
                        b: 0.25,
                        a: 1.0,
                    },
                    size: 64.0,
                }),
                View::new(IconView {
                    color: Color {
                        r: 0.25,
                        g: 1.0,
                        b: 0.25,
                        a: 1.0,
                    },
                    size: 64.0,
                }),
                View::new(IconView {
                    color: Color {
                        r: 0.25,
                        g: 0.25,
                        b: 1.0,
                        a: 1.0,
                    },
                    size: 64.0,
                }),
            ],
        }),
    });

    RauiQuickStartBuilder::default()
        .window_title("Retained mode UI".to_owned())
        .widget_tree(app.component().key("app").into())
        .build()
        .unwrap()
        .run()
        .unwrap();
}