30 lines
660 B
Haskell
30 lines
660 B
Haskell
import Graphics.UI.Gtk
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import Data.IORef
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main :: IO ()
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main = do
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initGUI
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window <- windowNew
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window `onDestroy` mainQuit
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windowSetTitle window "Simple Windowed App"
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set window [ containerBorderWidth := 10 ]
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hbox <- hBoxNew True 5
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set window [ containerChild := hbox ]
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lab <- labelNew (Just "There have been no clicks yet")
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button <- buttonNewWithLabel "Click me"
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set hbox [ containerChild := lab ]
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set hbox [ containerChild := button ]
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m <- newIORef 0
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onClicked button $ do
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v <- readIORef m
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writeIORef m (v+1)
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set lab [ labelText := "There have been " ++ show (v+1) ++ " clicks" ]
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widgetShowAll window
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mainGUI
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