re-order - Githubissues

Working on a prototype to get sorting to work:
use floem::{
    peniko::Color,
    reactive::{create_rw_signal, RwSignal},
    views::{container, dyn_stack, label, Decorators},
    IntoView,
};

fn sortable_item(
    view: impl IntoView + 'static,
    sortable_items: RwSignal<Vec<usize>>,
    hover_id: usize,
    dragger_id: RwSignal<usize>,
) -> impl IntoView {
    container(view)
        .style(|s| s.padding(5).selectable(false))
        .draggable()
        .on_event(floem::event::EventListener::DragOver, move |_| {
            sort_items(sortable_items, dragger_id.get(), hover_id);
            floem::event::EventPropagation::Continue
        })
        .on_event(floem::event::EventListener::DragStart, move |_| {
            dragger_id.set(hover_id);
            floem::event::EventPropagation::Continue
        })
        .on_event(floem::event::EventListener::DragEnd, move |_| {
            dragger_id.set(0);
            floem::event::EventPropagation::Continue
        })
}

fn sort_items(sortable_items: RwSignal<Vec<usize>>, dragger_id: usize, hover_id: usize) {
    if dragger_id != hover_id {
        sortable_items.update(|items| {
            let item = items.remove(dragger_id);
            items.insert(hover_id, item);
        })
    }
}

#[test]
fn sort_items_test() {
    // 0,1,2,3,4
    let sortable_items = create_rw_signal((0..5).collect::<Vec<usize>>());
    sort_items(sortable_items, 2, 1);
    assert_eq!(sortable_items.get(), vec![0, 2, 1, 3, 4]);

    let sortable_items = create_rw_signal((0..5).collect::<Vec<usize>>());
    sort_items(sortable_items, 4, 1);
    assert_eq!(sortable_items.get(), vec![0, 4, 1, 2, 3]);

    let sortable_items = create_rw_signal((0..5).collect::<Vec<usize>>());
    sort_items(sortable_items, 0, 2);
    assert_eq!(sortable_items.get(), vec![1, 2, 0, 3, 4]);

    let sortable_items = create_rw_signal((0..5).collect::<Vec<usize>>());
    sort_items(sortable_items, 2, 2);
    assert_eq!(sortable_items.get(), vec![0, 1, 2, 3, 4]);
}

fn sortable<V: IntoView + 'static>(items: Vec<impl Fn() -> V + 'static>) -> impl IntoView {
    let sortable_items = create_rw_signal((0..items.len()).collect::<Vec<usize>>());
    let dragger_id = create_rw_signal(0);

    dyn_stack(
        move || sortable_items.get(),
        move |item| *item,
        move |item| sortable_item(items[item](), sortable_items, item, dragger_id),
    )
    .into_any()
}

//////

fn my_view(name: &str) -> impl IntoView {
    let name = String::from(name);
    label(move || name.clone()).style(|s| {
        s.padding(5)
            .selectable(false)
            .border(2)
            .border_color(Color::RED)
    })
}

fn app_view() -> impl IntoView {
    sortable(vec![
        || my_view("line zero"),
        || my_view("line one"),
        || my_view("line two"),
        || my_view("line three"),
        || my_view("line four"),
        || my_view("line five"),
        || my_view("line six"),
        || my_view("line seven"),
        || my_view("line eight"),
        || my_view("line nine"),
        || my_view("line ten"),
    ])
    .style(|s| s.width_full().flex_col())
}

fn main() {
    floem::launch(app_view);
}
This is causing the view_fn to re-render each time the signal changes. What I need to fix here is for the key_fn to take the ordering instead.
dominikwilkowski / vault

re-order #84
