Update GridLayout to use CssListProperty for padding.

kivy/uix/gridlayout.py

@@ -90,7 +90,7 @@ __all__ = ('GridLayout', 'GridLayoutException')
 from kivy.logger import Logger
 from kivy.uix.layout import Layout
 from kivy.properties import NumericProperty, BooleanProperty, DictProperty, \
-        BoundedNumericProperty, ReferenceListProperty
+        BoundedNumericProperty, ReferenceListProperty, CssListProperty
 from math import ceil
 
 
@@ -111,11 +111,23 @@ class GridLayout(Layout):
     0.
     '''
 
-    padding = NumericProperty(0)
-    '''Padding between widget box and children, in pixels.
+    padding = CssListProperty([0, 0, 0, 0])
+    '''Padding between layout box and children, in pixels.
 
-    :data:`padding` is a :class:`~kivy.properties.NumericProperty`, default to
-    0.
+    padding[0] represents the left padding, padding[1] the right padding,
+    padding[2] the top padding and padding[3] the bottom padding.
+
+    If padding is given only two arguments, the first will represent left and
+    right padding, and the second top and bottom padding.
+
+    If padding is given only one argument, it will represent all four
+    directions.
+
+    .. versionchanged:: 1.7.0
+    Replaced NumericProperty with CssListProperty.
+
+    :data:`padding` is a :class:`~kivy.properties.CssListProperty`, default to
+    [0, 0, 0, 0].
     '''
 
     cols = BoundedNumericProperty(None, min=0, allow_none=True)
@@ -332,10 +344,11 @@ class GridLayout(Layout):
                 i = i - 1
 
         # calculate minimum width/height needed, starting from padding + spacing
-        padding2 = self.padding * 2
+        padding_x = self.padding[0] + self.padding[1]
+        padding_y = self.padding[2] + self.padding[3]
         spacing = self.spacing
-        width = padding2 + spacing * (current_cols - 1)
-        height = padding2 + spacing * (current_rows - 1)
+        width = padding_x + spacing * (current_cols - 1)
+        height = padding_y + spacing * (current_rows - 1)
         # then add the cell size
         width += sum(cols)
         height += sum(rows)
@@ -362,7 +375,8 @@ class GridLayout(Layout):
             return
 
         # speedup
-        padding = self.padding
+        padding_left = self.padding[0]
+        padding_top = self.padding[2]
         spacing = self.spacing
         selfx = self.x
         selfw = self.width
@@ -413,9 +427,9 @@ class GridLayout(Layout):
 
         # reposition every child
         i = len_children - 1
-        y = self.top - padding
+        y = self.top - padding_top
         for row_height in rows:
-            x = selfx + padding
+            x = selfx + padding_left
             for col_width in cols:
                 if i < 0:
                     break