it maths! what more could u want?

src/main.rs

@@ -1,6 +1,8 @@
 extern crate gtk;
 use gtk::prelude::*;
 use gtk::{Button, Window, WindowType};
+use std::cell::RefCell;
+use std::rc::Rc;
 
 enum Operators {
     PLUS,
@@ -13,6 +15,7 @@ struct Calc {
     left: String,
     right: String,
     operator: Option<Operators>,
+    label: gtk::Label,
 }
 
 impl Calc {
@@ -20,21 +23,41 @@ impl Calc {
         match self.operator {
             None => self.left.push_str(&button),
             Some(_) => self.right.push_str(&button),
-        }
+        };
+        self.display();
     }
-    fn eval(&mut self) -> u32 {
+    fn eval(&mut self) {
         let left = self.left.parse::<u32>().unwrap();
         let right = self.right.parse::<u32>().unwrap();
-        return match self.operator {
+        let ans = match self.operator {
             Some(Operators::PLUS) => left + right,
             Some(Operators::MINUS) => left - right,
             Some(Operators::DIVIDE) => left / right,
             Some(Operators::MULTIPLY) => left * right,
-            None => panic!("oh noes")
+            None => panic!("oh noes"),
-        }
+        };
+        self.right = String::new();
+        self.operator = None;
+        self.left = ans.to_string();
+        self.display();
     }
     fn new() -> Self {
-        Calc{left: String::new(), right: String::new(), operator: None}
+        Calc {
+            left: String::new(),
+            right: String::new(),
+            operator: None,
+            label: gtk::Label::new(Some("")),
+        }
+    }
+    fn display(&self) {
+        let text = match self.operator {
+            Some(Operators::PLUS) => self.left.clone() + "+" + &self.right,
+            Some(Operators::MINUS) => self.left.clone() + "-" + &self.right,
+            Some(Operators::DIVIDE) => self.left.clone() + "/" + &self.right,
+            Some(Operators::MULTIPLY) => self.left.clone() + "*" + &self.right,
+            None => self.left.clone(),
+        };
+        self.label.set_label(&text);
     }
 }
 
@@ -43,51 +66,133 @@ fn main() {
         println!("failed to init GTK");
         return;
     }
-    let calc = Calc::new();
+    let calc = Rc::new(RefCell::new(Calc::new()));
     let window: Window = Window::new(WindowType::Toplevel);
     window.set_title("Rust calc");
     let container = gtk::Box::new(gtk::Orientation::Vertical, 1);
+    // row 0
+    let cal0 = calc.clone();
+    container.add(&cal0.borrow().label);
     // row 1
     let row1 = gtk::Box::new(gtk::Orientation::Horizontal, 1);
     let button1 = Button::new_with_label("1");
     row1.add(&button1);
-    button1.connect_clicked(|but| calc.handle_number(but.get_label().unwrap()));
+    let cal1 = calc.clone();
+    button1.connect_clicked(move |but| {
+        cal1.borrow_mut().handle_number(but.get_label().unwrap());
+    });
+
     let button2 = Button::new_with_label("2");
     row1.add(&button2);
+    let cal2 = calc.clone();
+    button2.connect_clicked(move |but| {
+        cal2.borrow_mut().handle_number(but.get_label().unwrap());
+    });
+
     let button3 = Button::new_with_label("3");
     row1.add(&button3);
+    let cal3 = calc.clone();
+    button3.connect_clicked(move |but| {
+        cal3.borrow_mut().handle_number(but.get_label().unwrap());
+    });
+
     // row 2
     let row2 = gtk::Box::new(gtk::Orientation::Horizontal, 1);
     let button4 = Button::new_with_label("4");
     row2.add(&button4);
+    let cal4 = calc.clone();
+    button4.connect_clicked(move |but| {
+        cal4.borrow_mut().handle_number(but.get_label().unwrap());
+    });
+
     let button5 = Button::new_with_label("5");
     row2.add(&button5);
+    let cal5 = calc.clone();
+    button5.connect_clicked(move |but| {
+        cal5.borrow_mut().handle_number(but.get_label().unwrap());
+    });
+
     let button6 = Button::new_with_label("6");
     row2.add(&button6);
+    let cal6 = calc.clone();
+    button6.connect_clicked(move |but| {
+        cal6.borrow_mut().handle_number(but.get_label().unwrap());
+    });
+
     // row 3
     let row3 = gtk::Box::new(gtk::Orientation::Horizontal, 1);
     let button7 = Button::new_with_label("7");
     row3.add(&button7);
+    let cal7 = calc.clone();
+    button7.connect_clicked(move |but| {
+        cal7.borrow_mut().handle_number(but.get_label().unwrap());
+    });
+
     let button8 = Button::new_with_label("8");
     row3.add(&button8);
+    let cal8 = calc.clone();
+    button8.connect_clicked(move |but| {
+        cal8.borrow_mut().handle_number(but.get_label().unwrap());
+    });
+
     let button9 = Button::new_with_label("9");
     row3.add(&button9);
+    let cal9 = calc.clone();
+    button9.connect_clicked(move |but| {
+        cal9.borrow_mut().handle_number(but.get_label().unwrap());
+    });
+
     // row 4
     let row4 = gtk::Box::new(gtk::Orientation::Horizontal, 1);
     let button0 = Button::new_with_label("0");
     row4.add(&button0);
+    let cal0 = calc.clone();
+    button0.connect_clicked(move |but| {
+        cal0.borrow_mut().handle_number(but.get_label().unwrap());
+    });
+
     let button_sub = Button::new_with_label("-");
     row4.add(&button_sub);
+    let cal_sub = calc.clone();
+    button_sub.connect_clicked(move |_| {
+        let mut cal_sub_borrowed = cal_sub.borrow_mut();
+        cal_sub_borrowed.operator = Some(Operators::MINUS);
+        cal_sub_borrowed.display();
+    });
+
     let button_add = Button::new_with_label("+");
     row4.add(&button_add);
+    let cal_add = calc.clone();
+    button_add.connect_clicked(move |_| {
+        let mut cal_add_borrowed = cal_add.borrow_mut();
+        cal_add_borrowed.operator = Some(Operators::PLUS);
+        cal_add_borrowed.display();
+    });
     // row 5
     let row5 = gtk::Box::new(gtk::Orientation::Horizontal, 1);
     let button_mult = Button::new_with_label("*");
     row5.add(&button_mult);
+    let cal_mult = calc.clone();
+    button_mult.connect_clicked(move |_| {
+        let mut cal_mult_borrowed = cal_mult.borrow_mut();
+        cal_mult_borrowed.operator = Some(Operators::MULTIPLY);
+        cal_mult_borrowed.display();
+    });
     let button_div = Button::new_with_label("/");
     row5.add(&button_div);
+    let cal_div = calc.clone();
+    button_div.connect_clicked(move |_| {
+        let mut cal_div_borrowed = cal_div.borrow_mut();
+        cal_div_borrowed.operator = Some(Operators::DIVIDE);
+        cal_div_borrowed.display();
+    });
     let button_equals = Button::new_with_label("=");
     row5.add(&button_equals);
+    let cal_eq = calc.clone();
+    button_equals.connect_clicked(move |_| {
+        let mut cal_eq_borrowed = cal_eq.borrow_mut();
+        cal_eq_borrowed.eval();
+    });
     // add rows to window
     container.add(&row1);
     container.add(&row2);