Window is empty

[cr4zsci]

I'm trying to run the example code

{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE TemplateHaskell #-}

module Main where

import Control.Lens
import Data.Text (Text)
import Monomer
import TextShow

import qualified Monomer.Lens as L

newtype AppModel = AppModel {
  _clickCount :: Int
} deriving (Eq, Show)

data AppEvent
  = AppInit
  | AppIncrease
  deriving (Eq, Show)

makeLenses 'AppModel

buildUI
  :: WidgetEnv AppModel AppEvent
  -> AppModel
  -> WidgetNode AppModel AppEvent
buildUI wenv model = widgetTree where
  widgetTree = vstack [
      label "Hello world",
      spacer,
      hstack [
        label $ "Click count: " <> showt (model ^. clickCount),
        spacer,
        button "Increase count" AppIncrease
      ]
    ] `styleBasic` [padding 10]

handleEvent
  :: WidgetEnv AppModel AppEvent
  -> WidgetNode AppModel AppEvent
  -> AppModel
  -> AppEvent
  -> [AppEventResponse AppModel AppEvent]
handleEvent wenv node model evt = case evt of
  AppInit -> []
  AppIncrease -> [Model (model & clickCount +~ 1)]

main :: IO ()
main = do
  startApp model handleEvent buildUI config
  where
    config = [
      appWindowTitle "Tutorial 01 - Basics",
      -- appWindowIcon "./assets/images/icon.png",
      appTheme darkTheme,
      appFontDef "JetBrains Mono" "/home/yerkov/.local/share/fonts/JetBrainsMono-Bold.ttf",
      appInitEvent AppInit
      ]
    model = AppModel 0

But after running this code i get an empty window without widgets.

stack 2.11.1
ghc 9.4.7
Linux Mint 21.1

[fjvallarino]

Hi @cr4zsci,

Do you get any log/error in the console? It's probably failing to load the font. Does the same happen with Roboto Regular?

[cr4zsci]

Hi

There were no errors. After changing the font to roboto nothing changed: no errors and empty window.

p.s. sorry for the incorrect status changes

[fjvallarino]

It could be a driver issue. Are you able to run other OpenGL-based applications?

I searched on Google about Kaveri and OpenGL and found some people had different issues, but I could not find something definitive.

[cr4zsci]

glxgear works.