cursive/examples/src/bin/theme_manual.rs

use cursive::theme::{BaseColor, BorderStyle, Color, ColorStyle};
use cursive::views::{Dialog, EditView, LinearLayout, TextView};
use cursive::Cursive;

fn main() {
    let mut siv = cursive::default();

    let layout = LinearLayout::vertical()
        .child(TextView::new("This is a dynamic theme example!"))
        .child(EditView::new().content("Woo! colors!").style(
            ColorStyle::new(
                Color::Rgb(200, 150, 150),
                Color::Dark(BaseColor::Blue),
            ),
        ));

    siv.add_layer(
        Dialog::around(layout)
            .button("Change", |s| {
                let mut theme = s.current_theme().clone();

                theme.shadow = !theme.shadow;
                theme.borders = match theme.borders {
                    BorderStyle::Simple => BorderStyle::Outset,
                    BorderStyle::Outset => BorderStyle::None,
                    BorderStyle::None => BorderStyle::Simple,
                };

                s.set_theme(theme);
            })
            .button("Quit", Cursive::quit),
    );

    siv.run();
}