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(**************************************************************************)
(* Lablgtk - Examples *)
(* *)
(* This code is in the public domain. *)
(* You may freely copy parts of it in your application. *)
(* *)
(**************************************************************************)
(* $Id$ *)
open StdLabels
(* lablgladecc3 project2.ui > project2.ml *)
(* #use "project2.ml";; *)
open Project2
let w1 = new window1 ()
let numbers =
[| w1#button0; w1#button1; w1#button2; w1#button3; w1#button4;
w1#button5; w1#button6; w1#button7; w1#button8; w1#button9 |]
let label = w1#label1
type state = Input | Result
let state = ref Result
let pending = ref (fun x -> x)
let insert_digit n =
let prev = if !state = Result then "" else label#text in
label#set_text (prev ^ string_of_int n);
state := Input
let get_float () = float_of_string label#text
let insert_dot () =
let prev = label#text in
if not (String.contains prev '.') then label#set_text (prev ^ ".")
let set_pending f =
pending := f (get_float ()); state := Result
let equals () =
if !state = Input then
label#set_text (string_of_float (!pending (get_float())));
state := Result
let _ =
w1#toplevel#connect#destroy ~callback:GMain.quit;
for i = 0 to 9 do
numbers.(i)#connect#clicked ~callback:(fun () -> insert_digit i)
done;
w1#button_dot#connect#clicked ~callback:insert_dot;
List.iter ~f:
begin fun (b, f) ->
ignore (b#connect#clicked ~callback:(fun () -> set_pending f))
end
[ w1#button_add, (+.); w1#button_sub, (-.); w1#button_mul, ( *. );
w1#button_div, (fun x y -> if y = 0. then 0. else x/.y) ];
w1#button_eq#connect#clicked ~callback:equals;
w1#window1#event#connect#key_press ~callback:
begin fun ev ->
let key = GdkEvent.Key.string ev in
if String.length key <> 1 then false else begin
begin match key.[0] with
| '0'..'9' -> insert_digit (int_of_string key)
| '.' -> insert_dot ()
| '+' -> set_pending (+.)
| '-' -> set_pending (-.)
| '*' -> set_pending ( *. )
| '/' -> set_pending (fun x y -> if y = 0. then 0. else x/.y)
| '=' -> equals ()
| 'q' -> GMain.Main.quit ()
| _ -> ()
end;
true
end
end;
GMain.Main.main ()
|
