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module Main where
import Control.Monad (void)
import Control.Monad.State (put)
import Graphics.Vty
( white, blue, green, yellow, black, magenta
, Event(EvKey)
, Key(KChar, KEsc)
)
import Brick.Main
import Brick.Themes
( Theme
, newTheme
, themeToAttrMap
)
import Brick.Types
( Widget
, BrickEvent(VtyEvent)
, EventM
)
import Brick.Widgets.Center
( hCenter
, center
)
import Brick.Widgets.Core
( (<+>)
, vBox
, str
, hLimit
, withDefAttr
)
import Brick.Util (on, fg)
import Brick.AttrMap (AttrName, attrName)
ui :: Widget n
ui =
center $
hLimit 40 $
vBox $ hCenter <$>
[ str "Press " <+> (withDefAttr keybindingAttr $ str "1") <+> str " to switch to theme 1."
, str "Press " <+> (withDefAttr keybindingAttr $ str "2") <+> str " to switch to theme 2."
]
keybindingAttr :: AttrName
keybindingAttr = attrName "keybinding"
theme1 :: Theme
theme1 =
newTheme (white `on` blue)
[ (keybindingAttr, fg magenta)
]
theme2 :: Theme
theme2 =
newTheme (green `on` black)
[ (keybindingAttr, fg yellow)
]
appEvent :: BrickEvent () e -> EventM () Int ()
appEvent (VtyEvent (EvKey (KChar '1') [])) = put 1
appEvent (VtyEvent (EvKey (KChar '2') [])) = put 2
appEvent (VtyEvent (EvKey (KChar 'q') [])) = halt
appEvent (VtyEvent (EvKey KEsc [])) = halt
appEvent _ = return ()
app :: App Int e ()
app =
App { appDraw = const [ui]
, appHandleEvent = appEvent
, appStartEvent = return ()
, appAttrMap = \s ->
-- Note that in practice this is not ideal: we don't want
-- to build an attribute map from a theme every time this is
-- invoked, because it gets invoked once per redraw. Instead
-- we'd build the attribute map at startup and store it in
-- the application state. Here I just use themeToAttrMap to
-- show the mechanics of the API.
themeToAttrMap $ if s == 1
then theme1
else theme2
, appChooseCursor = neverShowCursor
}
main :: IO ()
main = void $ defaultMain app 1
|
