Add background color to size message.

Added a colored background to the label because it kept getting lost in
the white ‘K’ field.  Also changed the label color to cyan for
readability.

examples/canvas/repeat_texture.py

@@ -7,10 +7,19 @@ This was a test to fix an issue with repeating texture and window reloading.
 
 from kivy.app import App
 from kivy.uix.image import Image
-from kivy.properties import ObjectProperty
+from kivy.uix.label import Label
+from kivy.properties import ObjectProperty, ListProperty
 from kivy.lang import Builder
 
 kv = '''
+<LabelOnBackground>:
+    canvas.before:
+        Color:
+            rgb:   self.background
+        Rectangle:
+            pos:   self.pos
+            size:  self.size
+
 FloatLayout:
     canvas.before:
         Color:
@@ -20,11 +29,22 @@ FloatLayout:
             size: self.size
             texture: app.texture
 
-    Label:
+    LabelOnBackground:
         text: '{} (try to resize the window)'.format(root.size)
+        color: (0.4, 1, 1, 1)
+        background: (.3, .3, .3)
+        pos_hint: {'center_x': .5, 'center_y': .5 }
+        size_hint: None, None
+        height: 30
+        width: 250
+
 '''
 
 
+class LabelOnBackground(Label):
+    background = ListProperty((0.2, 0.2, 0.2))
+
+
 class RepeatTexture(App):
 
     texture = ObjectProperty()