Cursive ui, iteration and mutation of values in rust

cursive.rs

use cursive::{
    self, traits::Boxable, traits::Nameable, views::Button, views::Dialog, views::DummyView,
    views::EditView, views::LinearLayout, views::SelectView, Cursive,
};

fn main() {
    let mut siv = cursive::default();
    let select = SelectView::<String>::new()
        .on_submit(on_submit)
        .with_name("select")
        .fixed_size((10, 5));

    let buttons = LinearLayout::vertical()
        .child(Button::new("Add new", add_name))
        .child(Button::new("Delete", delete_name))
        .child(DummyView)
        .child(Button::new("Quit", Cursive::quit));

    siv.add_layer(
        Dialog::around(
            LinearLayout::horizontal()
                .child(select)
                .child(DummyView)
                .child(buttons),
        )
        .title("Select a profile"),
    );

    siv.run();
}

fn add_name(s: &mut Cursive) {
    fn ok(s: &mut Cursive, name: &str) {
        s.call_on_name("select", |view: &mut SelectView<String>| {
            view.add_item_str(name)
        });
        s.pop_layer();
    }

    let edt_view = EditView::new()
        .on_submit(ok)
        .with_name("name")
        .fixed_width(10);

    let dialog = Dialog::around(edt_view)
        .title("Enter a new name")
        .button("Ok", |s| {
            let name = s
                .call_on_name("name", |view: &mut EditView| view.get_content())
                .unwrap();
            ok(s, &name);
        })
        .button("Cancel", |s| {
            s.pop_layer();
        });
    
    s.add_layer(dialog);
}

fn delete_name(s: &mut Cursive) {
    let mut select = s.find_name::<SelectView<String>>("select").unwrap();
    match select.selected_id() {
        None => s.add_layer(Dialog::info("No name to remove")),
        Some(focus) => {
            select.remove_item(focus);
        }
    }
}

fn on_submit(s: &mut Cursive, name: &str) {
    s.pop_layer();
    let dialog = Dialog::text(format!("Name: {}\nAwesome: yes", name))
        .title(format!("{}'s info", name))
        .button("Quit", Cursive::quit);
    s.add_layer(dialog);
}