How to make a dynamic menu in rust 📃

#rust #programming #tutorial #terminal

In this article I am going to show you how to make a dynamic menu in Rust. First of all, let's add a lightweight keyboard event handler, I'll use k_board.

cargo add k_board

Then let's put together the program logic and match the results after receiving the enter as a parameter.

use std::io::Write;

fn main() {
    let mut option: u8 = 0;
    show_option('*', ' ');
    for key in k_board::Keyboard::new() {
        match key {
            k_board::Keys::Up => option =  0 ,
            k_board::Keys::Down => option = 1,
            k_board::Keys::Enter => break,
            _ => {}
        }
        match option {
            0 => show_option('*', ' '),
            1 => show_option(' ', '*'),
            _ => {}
        }
    }
    clear_screen();
    println!("Enter the text you want to print");
    let mut text: String = String::new();
    let _ = std::io::stdout().flush();
    std::io::stdin().read_line(&mut text).expect("Error");
    clear_screen();
    match option {
        0 => {
            println!("{}", text);
        }
        1 => unsafe {
            printf("%s\0".as_ptr(), text.as_ptr());
        },
        _ => {}
    }
}

fn clear_screen() {
    std::process::Command::new("clear").status().unwrap();
}

fn show_option(op1: char, op2: char) {
    clear_screen();
    println!(
        "{} print in RUST\n{} print in C",
        op1, op2
    );
}

extern "C" {
    fn printf(format: *const u8, ...) -> i32;
}