Added AlphaBox widget

lib/Phi/Border.hs

@@ -125,4 +125,4 @@ roundRectangle x y width height radius = do
   closePath
 
 border :: BorderConfig -> [Widget] -> Widget
-border config widgets = Widget $ Border config widgets
+border config = Widget . Border config

lib/Phi/Widgets/AlphaBox.hs

@@ -0,0 +1,49 @@
+{-# LANGUAGE TypeFamilies #-}
+
+module Phi.Widgets.AlphaBox ( alphaBox
+                            ) where
+
+import Phi.Types
+import Phi.Widget
+
+import Control.Monad
+
+import Graphics.Rendering.Cairo
+
+
+data AlphaBoxState = AlphaBoxState [WidgetState] deriving Show
+
+data AlphaBox = AlphaBox Double [Widget] deriving Show
+
+
+instance WidgetClass AlphaBox where
+  type WidgetData AlphaBox = AlphaBoxState
+  initWidget (AlphaBox _ widgets) phi disp = liftM AlphaBoxState $ mapM (createWidgetState phi disp) widgets
+  
+  minSize (AlphaBox _ _) (AlphaBoxState widgetStates) height =
+    sum (map (\(WidgetState {stateWidget = w, statePrivateData = priv}) -> minSize w priv height) widgetStates)
+  
+  weight (AlphaBox _ widgets) = sum (map (\(Widget w) -> weight w) widgets)
+  
+  layout (AlphaBox _ _) (AlphaBoxState widgetStates) width height = AlphaBoxState $ layoutWidgets widgetStates 0 0 width height
+
+  render (AlphaBox alpha _) (AlphaBoxState widgetStates) w h screen = do
+    renderWithSimilarSurface ContentColorAlpha w h $ \surface -> do
+      renderWith surface $ do
+        renderWidgets widgetStates screen
+        
+        setOperator OperatorDestIn
+        setSourceRGBA 0 0 0 alpha
+        paint
+      
+      withPatternForSurface surface setSource
+      paint
+        
+        
+    
+  handleMessage _ (AlphaBoxState widgetStates) m = AlphaBoxState $ handleMessageWidgets m widgetStates
+
+
+alphaBox :: Double -> [Widget] -> Widget
+alphaBox alpha = Widget . AlphaBox alpha
+