如何在Gtk2hs Cairo中检查渲染状态是否保存，以防止在Haskell中缩放窗口上的图像缩放

import Graphics.UI.Gtk
import Graphics.Rendering.Cairo

-- 检查渲染状态是否保存的函数
isRenderSaved :: Render Bool
isRenderSaved = do
  status <- cairoStatus
  case status of
    StatusSuccess -> return True
    _ -> return False

-- 绘制函数
draw :: DrawingArea -> EventM EExpose Bool
draw canvas = liftIO $ do
  -- 获取绘图上下文
  win <- widgetGetDrawWindow canvas
  (width, height) <- widgetGetSize canvas
  renderWithDrawable win $ do
    -- 在此处进行绘制操作
    -- ...

    -- 检查渲染状态是否保存
    saved <- isRenderSaved
    liftIO $ putStrLn $ "Render saved: " ++ show saved

    -- ...

  return True

main :: IO ()
main = do
  -- 初始化GTK
  _ <- initGUI

  -- 创建窗口和画布
  window <- windowNew
  canvas <- drawingAreaNew

  -- 设置窗口属性
  set window [windowDefaultWidth := 800, windowDefaultHeight := 600]

  -- 将画布添加到窗口中
  containerAdd window canvas

  -- 绑定绘制事件
  _ <- canvas `on` exposeEvent $ draw canvas

  -- 显示窗口
  widgetShowAll window

  -- 开始主循环
  mainGUI