1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
|
module tut10_4_2
// ********************************************************************************
// Clean tutorial example program.
//
// This program defines a Controls component that implements a manually settable
// counter. A receiver is used to add a reset option.
// ********************************************************************************
import StdEnv, StdIO
Start :: *World -> *World
Start world = startIO NDI Void initialise [] world
where
initialise pst
# (displayId, pst) = accPIO openId pst
# (resetId, pst) = accPIO openRId pst
# (error, pst) = openDialog Void (dialog displayId resetId) pst
| error <> NoError = abort "Counter could not open Dialog."
| otherwise = pst
dialog displayId resetId = Dialog "Counter" (counter :+: resetButton) [WindowClose (noLS closeProcess)]
where
counter = { newLS = initcount,
newDef = LayoutControl (EditControl (toString initcount) (PixelWidth (hmm 50.0)) 1 [ControlId displayId, ControlSelectState Unable] :+:
ButtonControl "-" [ControlFunction (count(-1)), ControlWidth (PixelWidth (hmm 25.0)), ControlPos (BelowPrev, zero)] :+:
ButtonControl "+" [ControlFunction (count 1 ), ControlWidth (PixelWidth (hmm 25.0))] :+:
Receiver resetId reset [])
[ControlPos (Center, zero), ControlHMargin 0 0, ControlVMargin 0 0, ControlItemSpace 0 0] }
where
initcount = 0
count :: Int (Int, PSt .l) -> (Int, PSt .l)
count dx (count, pst) = (count + dx, appPIO (setControlText displayId (toString (count+dx))) pst)
reset :: m (Int, PSt .l) -> (Int, PSt .l)
reset _ (_, pst) = (initcount, appPIO (setControlText displayId (toString initcount)) pst)
resetButton = ButtonControl "Reset" [ControlFunction (noLS (snd o syncSend resetId undef)), ControlPos (Center, zero)]
|