Add support for text styles - Work In Progress

sky/sdk/lib/framework/rendering/paragraph.dart

Index: sky/sdk/lib/framework/rendering/paragraph.dart
diff --git a/sky/sdk/lib/framework/rendering/paragraph.dart b/sky/sdk/lib/framework/rendering/paragraph.dart
index c0823a7b591e1456d9e54bf315baaaf46c38a6ed..2afc8337c8a94ffcbe687c361342c3f64ed4e183 100644
--- a/sky/sdk/lib/framework/rendering/paragraph.dart
+++ b/sky/sdk/lib/framework/rendering/paragraph.dart
@@ -11,6 +11,23 @@ class RenderInline extends RenderObject {
   String data;
 }
 
+class TextStyle {
+  final Color color;

[Hixie, 2015/06/11 17:39:28]

constructor then fields (see sky/specs/style-guide.md)

+  final String fontSize;

[Hixie, 2015/06/11 17:39:27]

fontSize should be a double (pixels).

+  final String fontWeight;

[Hixie, 2015/06/11 17:39:27]

fontWeight should be an enum.

+
+  const TextStyle({
+    this.color,
+    this.fontSize,
+    this.fontWeight
+  });
+
+  bool operator ==(other) => other is TextStyle &&

[Hixie, 2015/06/11 17:39:28]

If you have an operator ==, you need a hashCode function.

Also, only use => if it fits on one line.

+    color == other.color &&
+    fontSize == other.fontSize &&
+    fontWeight == other.fontWeight;
+}
+
 // Unfortunately, using full precision floating point here causes bad layouts
 // because floating point math isn't associative. If we add and subtract
 // padding, for example, we'll get different values when we estimate sizes and
@@ -26,8 +43,9 @@ class RenderParagraph extends RenderBox {
 
   RenderParagraph({
     String text,
-    Color color
-  }) : _color = color {
+    Color color,
+    TextStyle style
+  }) : _color = color, _style = style {
     _layoutRoot.rootElement = _document.createElement('p');
     this.text = text;
   }
@@ -41,6 +59,7 @@ class RenderParagraph extends RenderBox {
     markNeedsLayout();
   }
 
+  // TODO(hansmuller): remove this
   Color _color = const Color(0xFF000000);
   Color get color => _color;
   void set color (Color value) {
@@ -50,6 +69,16 @@ class RenderParagraph extends RenderBox {
     }
   }
 
+  TextStyle _style;
+  TextStyle get style => _style;
+  void set style (TextStyle value) {
+    if (_style != value) {
+      _style = value;
+      // TODO(hansmuller): decide if a new layout or paint is needed
+      markNeedsLayout();
+    }
+  }
+
   BoxConstraints _constraintsForCurrentLayout;
 
   sky.Element _layout(BoxConstraints constraints) {
@@ -106,9 +135,10 @@ class RenderParagraph extends RenderBox {
     if (_constraintsForCurrentLayout != constraints && constraints != null)
       _layout(constraints);
 
-    if (_color != null) {
+    if (style != null && style.color != null) {
+      Color color = style.color;
       _layoutRoot.rootElement.style['color'] =
-          'rgba(${_color.red}, ${_color.green}, ${_color.blue}, ${_color.alpha / 255.0 })';
+          'rgba(${color.red}, ${color.green}, ${color.blue}, ${color.alpha / 255.0 })';
     }
     _layoutRoot.paint(canvas);
   }