use fltk::{
app,
button::Button,
enums::{Color, Event, FrameType, Key, Shortcut},
group::{Pack, PackType},
output::Output,
prelude::*,
window::Window,
};
use std::ops::{Deref, DerefMut};
#[derive(Debug, Copy, Clone, PartialEq)]
enum Ops {
None,
Add,
Sub,
Mul,
Div,
Eq,
CE,
C,
Back,
}
#[derive(Debug, Copy, Clone)]
enum Message {
Number(i32),
Op(Ops),
Dot,
}
struct MyButton {
btn: Button,
}
impl MyButton {
pub fn new(title: &'static str) -> MyButton {
let mut b = MyButton {
btn: Button::new(0, 0, 100, 0, title),
};
b.set_label_size(24);
b.set_frame(FrameType::FlatBox);
match title {
"CE" => {
b.set_color(Color::from_hex(0xd50000));
b.set_shortcut(Shortcut::None | Key::Delete);
}
"x" | "/" | "+" | "-" | "=" | "C" | "@<-" => {
b.set_color(Color::from_hex(0xffee58));
b.set_label_color(Color::Black);
let shortcut = if title == "x" {
'*'
} else {
title.chars().next().unwrap()
};
b.set_shortcut(Shortcut::None | shortcut);
if shortcut == '@' {
b.set_shortcut(Shortcut::None | Key::BackSpace);
}
if shortcut == '=' {
b.set_shortcut(Shortcut::None | Key::Enter);
}
}
_ => {
if title == "0" {
b.resize(0, 0, 100 * 2, 0);
}
b.set_label_color(Color::White);
b.set_selection_color(Color::from_hex(0x1b1b1b));
b.set_shortcut(Shortcut::None | title.chars().next().unwrap());
b.handle(move |b, ev| match ev {
Event::Enter => {
b.set_color(Color::from_hex(0x2b2b2b));
b.redraw();
true
}
Event::Leave => {
b.set_color(Color::from_hex(0x424242));
b.redraw();
true
}
_ => false,
});
}
}
b
}
}
impl Deref for MyButton {
type Target = Button;
fn deref(&self) -> &Self::Target {
&self.btn
}
}
impl DerefMut for MyButton {
fn deref_mut(&mut self) -> &mut Self::Target {
&mut self.btn
}
}
fn main() {
let app = app::App::default();
app::set_visible_focus(false);
app::background(0x42, 0x42, 0x42);
app::background2(0x1b, 0x1b, 0x1b);
let win_w = 400;
let win_h = 500;
let but_row = 160;
let mut operation = Ops::None;
let mut txt = String::from("0");
let mut old_val = String::from("0");
let mut new_val: String;
let mut wind = Window::default()
.with_label("FLTK Calc")
.with_size(win_w, win_h)
.center_screen();
let mut out = Output::new(0, 0, win_w, 160, "");
out.set_frame(FrameType::FlatBox);
out.set_text_color(Color::White);
out.set_text_size(36);
out.set_value("0");
let vpack = Pack::new(0, but_row, win_w, win_h - 170, "");
let mut hpack = Pack::new(0, 0, win_w, 68, "");
let but_ce = MyButton::new("CE");
let but_c = MyButton::new("C");
let but_back = MyButton::new("@<-");
let but_div = MyButton::new("/");
hpack.end();
hpack.set_type(PackType::Horizontal);
let mut hpack = Pack::new(0, 0, win_w, 68, "");
let mut but7 = MyButton::new("7");
let mut but8 = MyButton::new("8");
let mut but9 = MyButton::new("9");
let but_mul = MyButton::new("x");
hpack.end();
hpack.set_type(PackType::Horizontal);
let mut hpack = Pack::new(0, 0, win_w, 68, "");
let mut but4 = MyButton::new("4");
let mut but5 = MyButton::new("5");
let mut but6 = MyButton::new("6");
let but_sub = MyButton::new("-");
hpack.end();
hpack.set_type(PackType::Horizontal);
let mut hpack = Pack::new(0, 0, win_w, 68, "");
let mut but1 = MyButton::new("1");
let mut but2 = MyButton::new("2");
let mut but3 = MyButton::new("3");
let but_add = MyButton::new("+");
hpack.end();
hpack.set_type(PackType::Horizontal);
let mut hpack = Pack::new(0, 0, win_w, 68, "");
let mut but_dot = MyButton::new(".");
let mut but0 = MyButton::new("0");
let but_eq = MyButton::new("=");
hpack.end();
hpack.set_type(PackType::Horizontal);
vpack.end();
wind.make_resizable(false);
wind.end();
wind.show();
app::set_focus(&*but1);
let but_vec = vec![
&mut but1, &mut but2, &mut but3, &mut but4, &mut but5, &mut but6, &mut but7, &mut but8,
&mut but9, &mut but0,
];
let but_op_vec = vec![
but_add, but_sub, but_mul, but_div, but_c, but_ce, but_back, but_eq,
];
let (s, r) = app::channel::<Message>();
for but in but_vec {
let label = but.label();
but.emit(s, Message::Number(label.parse().unwrap()));
}
for mut but in but_op_vec {
let label = but.label().clone();
let op = match label.as_str() {
"+" => Ops::Add,
"-" => Ops::Sub,
"x" => Ops::Mul,
"/" => Ops::Div,
"=" => Ops::Eq,
"CE" => Ops::CE,
"C" => Ops::C,
"@<-" => Ops::Back,
_ => Ops::None,
};
but.emit(s, Message::Op(op));
}
but_dot.emit(s, Message::Dot);
while app.wait() {
if let Some(val) = r.recv() {
match val {
Message::Number(num) => {
if out.value() == "0" {
txt.clear();
}
txt.push_str(&num.to_string());
out.set_value(txt.as_str());
}
Message::Dot => {
if operation == Ops::Eq {
txt.clear();
operation = Ops::None;
out.set_value("0.");
txt.push_str("0.");
}
if !txt.contains('.') {
txt.push('.');
out.set_value(txt.as_str());
}
}
Message::Op(op) => match op {
Ops::Add | Ops::Sub | Ops::Div | Ops::Mul => {
old_val.clear();
old_val.push_str(&out.value());
operation = op;
out.set_value("0");
}
Ops::Back => {
let val = out.value();
if val.len() > 1 {
txt.pop();
out.set_value(txt.as_str());
}
}
Ops::CE => {
txt.clear();
old_val.clear();
txt.push('0');
out.set_value(txt.as_str());
}
Ops::C => {
txt.clear();
txt.push('0');
out.set_value(txt.as_str());
}
Ops::Eq => {
new_val = out.value();
let old: f64 = old_val.parse().unwrap();
let new: f64 = new_val.parse().unwrap();
let val = match operation {
Ops::Div => old / new,
Ops::Mul => old * new,
Ops::Add => old + new,
Ops::Sub => old - new,
_ => new,
};
operation = Ops::None;
txt = String::from("0");
out.set_value(&val.to_string());
}
_ => (),
},
}
}
}
}