Hoist knowledge of image_cache into widgets/basic.dart

sky/sdk/lib/widgets/basic.dart

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'dart:async';
 import 'dart:sky' as sky;
 
 import 'package:vector_math/vector_math.dart';
 
+import '../mojo/net/image_cache.dart' as image_cache;
 import '../painting/text_style.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 'default_text_style.dart';
 import 'widget.dart';
 
@@ skipping 451 matching lines @@
   Widget build() {
     InlineBase text = new InlineText(data);
     TextStyle defaultStyle = DefaultTextStyle.of(this);
     TextStyle combinedStyle;
     if (defaultStyle != null) {
       if (style != null)
         combinedStyle = defaultStyle.merge(style);
       else
         combinedStyle = defaultStyle;
     } else {
-      combinedStyle = style;      
+      combinedStyle = style;
     }
     if (combinedStyle != null)
       text = new InlineStyle(combinedStyle, [text]);
     return new Inline(text: text);
   }
 }
 
 class Image extends LeafRenderObjectWrapper {
+  Image({ sky.Image image, this.size })
+    : image = image, super(key: image.hashCode.toString());
 
-  Image({
-    src,
-    this.size
-  }) : src = src,
-       super(key: src) {
-    assert(src != null);
+  RenderImage get root => super.root;
+  RenderImage createNode() => new RenderImage(image, size);
+
+  final sky.Image image;
+  final Size size;
+
+  void syncRenderObject(Widget old) {
+    super.syncRenderObject(old);
+    root.image = image;
+    root.requestedSize = size;
+  }
+}
+
+class FutureImage extends Component {
+  FutureImage({ this.image, this.size }) : super(stateful: true);
+
+  Future<sky.Image> image;
+  Size size;
+  sky.Image _resolvedImage;
+
+  void didMount() {
+    super.didMount();
+    _resolveImage();
   }
 
-  RenderImage get root => super.root;
-  RenderImage createNode() => new RenderImage(this.src, this.size);
+  void _resolveImage() {
+    image.then((sky.Image resolvedImage) {
+      if (!mounted)
+        return;
+      setState(() {
+        _resolvedImage = resolvedImage;
+      });
+    });
+  }
+
+  void syncFields(FutureImage source) {
+    bool needToResolveImage = (image != source.image);
+    image = source.image;
+    size = source.size;
+    if (needToResolveImage)
+      _resolveImage();
+  }
+
+  Widget build() {
+    return new Image(image: _resolvedImage, size: size);
+  }
+}
+
+class NetworkImage extends Component {
+  NetworkImage({ String src, this.size }) : src = src, super(key: src);
 
   final String src;
   final Size size;
 
-  void syncRenderObject(Widget old) {
-    super.syncRenderObject(old);
-    root.src = src;
-    root.requestedSize = size;
+  Widget build() {
+    return new FutureImage(image: image_cache.load(src), size: size);
   }
-
 }
 
 class WidgetToRenderBoxAdapter extends LeafRenderObjectWrapper {
 
   WidgetToRenderBoxAdapter(RenderBox renderBox)
     : renderBox = renderBox,
       super(key: renderBox.hashCode.toString());
 
   RenderBox get root => super.root;
   RenderBox createNode() => this.renderBox;
 
   final RenderBox renderBox;
 
   void syncRenderObject(Widget old) {
     super.syncRenderObject(old);
     if (old != null) {
       assert(old is WidgetToRenderBoxAdapter);
       assert(root == old.root);
     }
   }
 
   void remove() {
     RenderObjectWrapper ancestor = findAncestor(RenderObjectWrapper);
     assert(ancestor is RenderObjectWrapper);
     ancestor.detachChildRoot(this);
     super.remove();
   }
 
 }