Code shared from the Rust Playground

playground.rs

#![allow(unused)]

#[derive(Debug)]
struct TextEngine {
    id: u32,
}

#[derive(Debug)]
struct Ui {
    engine: TextEngine,
    labels: Vec<Label>,
}

#[derive(Debug)]
struct Label {
    id: String,
    text: String,
}

impl Ui {
    fn new(e: TextEngine) -> Self {
        let mut v: Vec<Label> = Vec::new();
        v.push(Label::new("op", "clear"));
        v.push(Label::new("mode", "over"));
        v.push(Label::new("tool", "pastel"));
        v.push(Label::new("tip", "4X"));
        Ui {
            engine: e,
            labels: v,
        }
    }
    
    fn get_label(&mut self, _id: &str) -> Option<&mut Label> {
        for l in self.labels.iter_mut() {
            if l.id == _id {
                return Some(l);
            }
        }
        None
    }
    
    fn set_mode(&mut self, mode: &str) {
        let res = self.get_label("mode");
        match res {
            Some(label) => {
                label.set_text(mode);
            }
            None => {
                println!("ERROR");
            }
        }
    }
}

impl Label {
    fn new(id: &str, text: &str) -> Label {
        Label {
            id: String::from(id),
            text: String::from(text),
        }
    }
    
    fn text(&self) -> &str {
        &self.text
    }
    
    fn set_text(&mut self, _text: &str) {
        self.text = String::from(_text);
    }
}

fn main() {
    let e = TextEngine { id:12 };
    let mut ui = Ui::new(e);
    ui.set_mode("under");
    println!("{:?}", ui);
}