1extern crate native_windows_gui2 as nwg;
6use nwg::NativeUi;
7
8#[derive(Debug)]
9enum Token {
10 Number(i32),
11 Plus,
12 Minus,
13 Mult,
14 Div,
15}
16
17#[derive(Default)]
18pub struct Calculator {
19 window: nwg::Window,
20
21 layout: nwg::GridLayout,
22
23 input: nwg::TextInput,
24
25 btn0: nwg::Button,
26 btn1: nwg::Button,
27 btn2: nwg::Button,
28 btn3: nwg::Button,
29 btn4: nwg::Button,
30 btn5: nwg::Button,
31 btn6: nwg::Button,
32 btn7: nwg::Button,
33 btn8: nwg::Button,
34 btn9: nwg::Button,
35
36 btn_plus: nwg::Button,
37 btn_minus: nwg::Button,
38 btn_mult: nwg::Button,
39 btn_divide: nwg::Button,
40 btn_process: nwg::Button,
41 btn_clear: nwg::Button,
42}
43
44impl Calculator {
45 fn number(&self, button: &nwg::Button) {
46 let text = self.input.text();
47 self.input.set_text(&format!("{}{}", text, button.text()));
48 }
49
50 fn clear(&self) {
51 self.input.set_text("");
52 }
53
54 fn compute(&self) {
55 use Token::*;
56 static SYMBOLS: &'static [char] = &['+', '-', '*', '/'];
57
58 let eq = self.input.text();
59 if eq.len() == 0 {
60 return;
61 }
62
63 let mut tokens: Vec<Token> = Vec::with_capacity(5);
64 let mut last = 0;
65
66 for (i, chr) in eq.char_indices() {
67 if SYMBOLS.iter().any(|&s| s == chr) {
68 let left = &eq[last..i];
69 match left.parse::<i32>() {
70 Ok(i) => tokens.push(Token::Number(i)),
71 _ => {
72 nwg::error_message("Error", "Invalid equation!");
73 self.input.set_text("");
74 return;
75 }
76 }
77
78 let tk = match chr {
79 '+' => Plus,
80 '-' => Minus,
81 '*' => Mult,
82 '/' => Div,
83 _ => unreachable!(),
84 };
85
86 tokens.push(tk);
87
88 last = i + 1;
89 }
90 }
91
92 let right = &eq[last..];
93 match right.parse::<i32>() {
94 Ok(i) => tokens.push(Token::Number(i)),
95 _ => {
96 nwg::error_message("Error", "Invalid equation!");
97 self.input.set_text("");
98 return;
99 }
100 }
101
102 let mut i = 1;
103 let mut result = match &tokens[0] {
104 Token::Number(n) => *n,
105 _ => unreachable!(),
106 };
107 while i < tokens.len() {
108 match [&tokens[i], &tokens[i + 1]] {
109 [Plus, Number(n)] => {
110 result += n;
111 }
112 [Minus, Number(n)] => {
113 result -= n;
114 }
115 [Mult, Number(n)] => {
116 result *= n;
117 }
118 [Div, Number(n)] => {
119 result /= n;
120 }
121 _ => unreachable!(),
122 }
123 i += 2;
124 }
125
126 self.input.set_text(&result.to_string());
127 }
128
129 fn exit(&self) {
130 nwg::stop_thread_dispatch();
131 }
132}
133
134mod calculator_ui {
138 use super::*;
139 use native_windows_gui2 as nwg;
140 use std::cell::RefCell;
141 use std::ops::Deref;
142 use std::rc::Rc;
143
144 pub struct CalculatorUi {
145 inner: Rc<Calculator>,
146 default_handler: RefCell<Vec<nwg::EventHandler>>,
147 }
148
149 impl nwg::NativeUi<CalculatorUi> for Calculator {
150 fn build_ui(mut data: Calculator) -> Result<CalculatorUi, nwg::NwgError> {
151 use nwg::Event as E;
152
153 nwg::Window::builder()
155 .size((300, 150))
156 .position((300, 300))
157 .title("Calculator")
158 .build(&mut data.window)?;
159
160 nwg::TextInput::builder()
161 .text("")
162 .align(nwg::HTextAlign::Right)
163 .readonly(true)
164 .parent(&data.window)
165 .build(&mut data.input)?;
166
167 nwg::Button::builder()
168 .text("1")
169 .parent(&data.window)
170 .focus(true)
171 .build(&mut data.btn1)?;
172
173 nwg::Button::builder()
174 .text("2")
175 .parent(&data.window)
176 .build(&mut data.btn2)?;
177 nwg::Button::builder()
178 .text("3")
179 .parent(&data.window)
180 .build(&mut data.btn3)?;
181 nwg::Button::builder()
182 .text("4")
183 .parent(&data.window)
184 .build(&mut data.btn4)?;
185 nwg::Button::builder()
186 .text("5")
187 .parent(&data.window)
188 .build(&mut data.btn5)?;
189 nwg::Button::builder()
190 .text("6")
191 .parent(&data.window)
192 .build(&mut data.btn6)?;
193 nwg::Button::builder()
194 .text("7")
195 .parent(&data.window)
196 .build(&mut data.btn7)?;
197 nwg::Button::builder()
198 .text("8")
199 .parent(&data.window)
200 .build(&mut data.btn8)?;
201 nwg::Button::builder()
202 .text("9")
203 .parent(&data.window)
204 .build(&mut data.btn9)?;
205 nwg::Button::builder()
206 .text("0")
207 .parent(&data.window)
208 .build(&mut data.btn0)?;
209
210 nwg::Button::builder()
211 .text("+")
212 .parent(&data.window)
213 .build(&mut data.btn_plus)?;
214 nwg::Button::builder()
215 .text("-")
216 .parent(&data.window)
217 .build(&mut data.btn_minus)?;
218 nwg::Button::builder()
219 .text("*")
220 .parent(&data.window)
221 .build(&mut data.btn_mult)?;
222 nwg::Button::builder()
223 .text("/")
224 .parent(&data.window)
225 .build(&mut data.btn_divide)?;
226 nwg::Button::builder()
227 .text("Clear")
228 .parent(&data.window)
229 .build(&mut data.btn_clear)?;
230 nwg::Button::builder()
231 .text("=")
232 .parent(&data.window)
233 .build(&mut data.btn_process)?;
234
235 let ui = CalculatorUi {
237 inner: Rc::new(data),
238 default_handler: Default::default(),
239 };
240
241 let window_handles = [&ui.window.handle];
243 for handle in window_handles.iter() {
244 let evt_ui = Rc::downgrade(&ui.inner);
245 let handle_events = move |evt, _evt_data, handle| {
246 if let Some(evt_ui) = evt_ui.upgrade() {
247 match evt {
248 E::OnButtonClick => {
249 if &handle == &evt_ui.btn0 {
250 Calculator::number(&evt_ui, &evt_ui.btn0);
251 } else if &handle == &evt_ui.btn1 {
252 Calculator::number(&evt_ui, &evt_ui.btn1);
253 } else if &handle == &evt_ui.btn2 {
254 Calculator::number(&evt_ui, &evt_ui.btn2);
255 } else if &handle == &evt_ui.btn3 {
256 Calculator::number(&evt_ui, &evt_ui.btn3);
257 } else if &handle == &evt_ui.btn4 {
258 Calculator::number(&evt_ui, &evt_ui.btn4);
259 } else if &handle == &evt_ui.btn5 {
260 Calculator::number(&evt_ui, &evt_ui.btn5);
261 } else if &handle == &evt_ui.btn6 {
262 Calculator::number(&evt_ui, &evt_ui.btn6);
263 } else if &handle == &evt_ui.btn7 {
264 Calculator::number(&evt_ui, &evt_ui.btn7);
265 } else if &handle == &evt_ui.btn8 {
266 Calculator::number(&evt_ui, &evt_ui.btn8);
267 } else if &handle == &evt_ui.btn9 {
268 Calculator::number(&evt_ui, &evt_ui.btn9);
269 } else if &handle == &evt_ui.btn_plus {
270 Calculator::number(&evt_ui, &evt_ui.btn_plus);
271 } else if &handle == &evt_ui.btn_minus {
272 Calculator::number(&evt_ui, &evt_ui.btn_minus);
273 } else if &handle == &evt_ui.btn_mult {
274 Calculator::number(&evt_ui, &evt_ui.btn_mult);
275 } else if &handle == &evt_ui.btn_divide {
276 Calculator::number(&evt_ui, &evt_ui.btn_divide);
277 } else if &handle == &evt_ui.btn_clear {
278 Calculator::clear(&evt_ui);
279 } else if &handle == &evt_ui.btn_process {
280 Calculator::compute(&evt_ui);
281 }
282 }
283 E::OnWindowClose => {
284 if &handle == &evt_ui.window {
285 Calculator::exit(&evt_ui);
286 }
287 }
288 _ => {}
289 }
290 }
291 };
292
293 ui.default_handler
294 .borrow_mut()
295 .push(nwg::full_bind_event_handler(handle, handle_events));
296 }
297
298 nwg::GridLayout::builder()
300 .parent(&ui.window)
301 .spacing(2)
302 .min_size([150, 140])
303 .child_item(nwg::GridLayoutItem::new(&ui.input, 0, 0, 5, 1))
304 .child(0, 1, &ui.btn1)
305 .child(1, 1, &ui.btn2)
306 .child(2, 1, &ui.btn3)
307 .child(0, 2, &ui.btn4)
308 .child(1, 2, &ui.btn5)
309 .child(2, 2, &ui.btn6)
310 .child(0, 3, &ui.btn7)
311 .child(1, 3, &ui.btn8)
312 .child(2, 3, &ui.btn9)
313 .child(3, 1, &ui.btn_plus)
314 .child(4, 1, &ui.btn_minus)
315 .child(3, 2, &ui.btn_mult)
316 .child(4, 2, &ui.btn_divide)
317 .child_item(nwg::GridLayoutItem::new(&ui.btn_clear, 3, 3, 2, 1))
318 .child_item(nwg::GridLayoutItem::new(&ui.btn_process, 3, 4, 2, 1))
319 .child_item(nwg::GridLayoutItem::new(&ui.btn0, 0, 4, 3, 1))
320 .build(&ui.layout)?;
321
322 return Ok(ui);
323 }
324 }
325
326 impl Drop for CalculatorUi {
327 fn drop(&mut self) {
329 let mut handlers = self.default_handler.borrow_mut();
330 for handler in handlers.drain(0..) {
331 nwg::unbind_event_handler(&handler);
332 }
333 }
334 }
335
336 impl Deref for CalculatorUi {
337 type Target = Calculator;
338
339 fn deref(&self) -> &Calculator {
340 &self.inner
341 }
342 }
343}
344
345fn main() {
346 nwg::init().expect("Failed to init Native Windows GUI");
347 nwg::Font::set_global_family("Segoe UI").expect("Failed to set default font");
348
349 let _app = Calculator::build_ui(Default::default()).expect("Failed to build UI");
350 nwg::dispatch_thread_events();
351}