Material and RaisedButton.

sky/sdk/lib/framework/widgets/wrappers.dart

 
 import 'package:vector_math/vector_math.dart';
 
 import '../rendering/block.dart';
 import '../rendering/box.dart';
 import '../rendering/flex.dart';
 import '../rendering/object.dart';
 import '../rendering/paragraph.dart';
 import '../rendering/stack.dart';
 import 'ui_node.dart';
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   RenderPadding createNode() => new RenderPadding(padding: padding);
 
   void syncRenderObject(Padding old) {
     super.syncRenderObject(old);
     root.padding = padding;
   }
 
 }
 
+class Center extends OneChildRenderObjectWrapper {
+
+  Center({ UINode child, Object key })
+    : super(child: child, key: key);
+
+  RenderPositionedBox get root { RenderPositionedBox result = super.root; return result; }
+
+  RenderPositionedBox createNode() => new RenderPositionedBox();
+
+}
+
 class SizedBox extends OneChildRenderObjectWrapper {
 
   SizedBox({
     double width: double.INFINITY,
     double height: double.INFINITY,
     UINode child,
     Object key
   }) : desiredSize = new Size(width, height), super(child: child, key: key);
 
   RenderSizedBox get root { RenderSizedBox result = super.root; return result; }
@@ skipping 225 matching lines @@
     root.src = src;
     root.requestedSize = size;
   }
 
   void insert(RenderObjectWrapper child, dynamic slot) {
     assert(false);
     // Image does not support having children currently
   }
 
 }