Breakout Step 1

breakout1.rs

use bevy::{
    prelude::*,
    render::pass::ClearColor,
};

fn main() {
    App::build()
        .add_plugins(DefaultPlugins)
        .insert_resource(ClearColor(Color::rgb(0.9, 0.9, 0.9)))
        .add_startup_system(setup.system())
        .add_system(paddle_movement_system.system())
        .run();
}

struct Paddle {
    speed: f32,
}

enum Collider {
    Solid,
    Scorable,
    Paddle,
}

fn setup(
    commands: &mut Commands,
    mut materials: ResMut<Assets<ColorMaterial>>,
    asset_server: Res<AssetServer>,
) {
    commands
        // cameras
        .spawn(OrthographicCameraBundle::new_2d())
        .spawn(UiCameraBundle::default())
        // paddle
        .spawn(SpriteBundle {
            material: materials.add(Color::rgb(0.5, 0.5, 1.0).into()),
            transform: Transform::from_xyz(0.0, -215.0, 0.0),
            sprite: Sprite::new(Vec2::new(120.0, 30.0)),
            ..Default::default()
        })
        .with(Paddle { speed: 500.0 })
        .with(Collider::Paddle);
}

fn paddle_movement_system(
    time: Res<Time>,
    keyboard_input: Res<Input<KeyCode>>,
    mut query: Query<(&Paddle, &mut Transform)>,
) {
    for (paddle, mut transform) in query.iter_mut() {
        let mut direction = 0.0;
        if keyboard_input.pressed(KeyCode::Left) {
            direction -= 1.0;
        }

        if keyboard_input.pressed(KeyCode::Right) {
            direction += 1.0;
        }

        let translation = &mut transform.translation;
        // move the paddle horizontally
        translation.x += time.delta_seconds() * direction * paddle.speed;
        // bound the paddle
        translation.x = translation.x.min(380.0).max(-380.0);
    }
}

Hello!
This code compiles but produces only a window with a gray background, without paddle...

I am sorry to hear that, unfortunately my tutorial was not accepted into the Bevy book, so I have stopped working on it... As such I probably won't dedicate any more time on it.