Radio button 'disabled' state.

Also:
 - give card_collection an option to turn on or off the edit widgets
 - give card_collection an option to control text alignment (when not editing)
 - give card_collection a "dump" option to aid debugging
 - make the gesture detector report which gestures it is listening to

examples/widgets/card_collection.dart

@@ -6,6 +6,7 @@ import 'dart:ui' as ui;
 
 import 'package:flutter/material.dart';
 import 'package:flutter/painting.dart';
+import 'package:flutter/rendering.dart';
 
 class CardModel {
   CardModel(this.value, this.height) {
@@ -36,6 +37,8 @@ class CardCollectionState extends State<CardCollection> {
   Map<int, Color> _primaryColor = Colors.deepPurple;
   List<CardModel> _cardModels;
   DismissDirection _dismissDirection = DismissDirection.horizontal;
+  TextStyle _textStyle = new TextStyle(textAlign: TextAlign.center);
+  bool _editable = true;
   bool _snapToCenter = false;
   bool _fixedSizeCards = false;
   bool _sunshine = false;
@@ -120,6 +123,7 @@ class CardCollectionState extends State<CardCollection> {
         data: const IconThemeData(color: IconThemeColor.black),
         child: new Block(<Widget>[
           new DrawerHeader(child: new Text('Options')),
+          buildDrawerCheckbox("Make card labels editable", _editable, _toggleEditable),
           buildDrawerCheckbox("Snap fling scrolls to center", _snapToCenter, _toggleSnapToCenter),
           buildDrawerCheckbox("Fixed size cards", _fixedSizeCards, _toggleFixedSizeCards),
           buildDrawerCheckbox("Let the sun shine", _sunshine, _toggleSunshine),
@@ -132,6 +136,16 @@ class CardCollectionState extends State<CardCollection> {
           buildDrawerDirectionRadioItem("Dismiss horizontally", DismissDirection.horizontal, _dismissDirection, _changeDismissDirection, icon: 'action/code'),
           buildDrawerDirectionRadioItem("Dismiss left", DismissDirection.left, _dismissDirection, _changeDismissDirection, icon: 'navigation/arrow_back'),
           buildDrawerDirectionRadioItem("Dismiss right", DismissDirection.right, _dismissDirection, _changeDismissDirection, icon: 'navigation/arrow_forward'),
+          new DrawerDivider(),
+          buildFontRadioItem("Left-align text", new TextStyle(textAlign: TextAlign.left), _textStyle, _changeTextStyle, icon: 'editor/format_align_left', enabled: !_editable),
+          buildFontRadioItem("Center-align text", new TextStyle(textAlign: TextAlign.center), _textStyle, _changeTextStyle, icon: 'editor/format_align_center', enabled: !_editable),
+          buildFontRadioItem("Right-align text", new TextStyle(textAlign: TextAlign.right), _textStyle, _changeTextStyle, icon: 'editor/format_align_right', enabled: !_editable),
+          new DrawerDivider(),
+          new DrawerItem(
+            icon: 'device/dvr',
+            onPressed: () { debugDumpApp(); debugDumpRenderTree(); },
+            child: new Text('Dump App to Console')
+          ),
         ])
       )
     );
@@ -142,6 +156,12 @@ class CardCollectionState extends State<CardCollection> {
     return "dismiss ${s.substring(s.indexOf('.') + 1)}";
   }
 
+  void _toggleEditable() {
+    setState(() {
+      _editable = !_editable;
+    });
+  }
+
   void _toggleFixedSizeCards() {
     setState(() {
       _fixedSizeCards = !_fixedSizeCards;
@@ -171,7 +191,12 @@ class CardCollectionState extends State<CardCollection> {
     setState(() {
       _dismissDirection = newDismissDirection;
     });
-    Navigator.of(context).pop();
+  }
+
+  void _changeTextStyle(TextStyle newTextStyle) {
+    setState(() {
+      _textStyle = newTextStyle;
+    });
   }
 
   Widget buildDrawerCheckbox(String label, bool value, void callback()) {
@@ -184,30 +209,48 @@ class CardCollectionState extends State<CardCollection> {
     );
   }
 
-  Widget buildDrawerColorRadioItem(String label, Map<int, Color> itemValue, Map<int, Color> currentValue, ValueChanged<Map<int, Color>> onChanged, { String icon }) {
+  Widget buildDrawerColorRadioItem(String label, Map<int, Color> itemValue, Map<int, Color> currentValue, ValueChanged<Map<int, Color>> onChanged, { String icon, bool enabled: true }) {
     return new DrawerItem(
       icon: icon,
-      onPressed: () { onChanged(itemValue); },
+      onPressed: enabled ? () { onChanged(itemValue); } : null,
       child: new Row(<Widget>[
         new Flexible(child: new Text(label)),
         new Radio<Map<int, Color>>(
           value: itemValue,
           groupValue: currentValue,
+          enabled: enabled,
           onChanged: onChanged
         )
       ])
     );
   }
 
-  Widget buildDrawerDirectionRadioItem(String label, DismissDirection itemValue, DismissDirection currentValue, ValueChanged<DismissDirection> onChanged, { String icon }) {
+  Widget buildDrawerDirectionRadioItem(String label, DismissDirection itemValue, DismissDirection currentValue, ValueChanged<DismissDirection> onChanged, { String icon, bool enabled: true }) {
     return new DrawerItem(
       icon: icon,
-      onPressed: () { onChanged(itemValue); },
+      onPressed: enabled ? () { onChanged(itemValue); } : null,
       child: new Row(<Widget>[
         new Flexible(child: new Text(label)),
         new Radio<DismissDirection>(
           value: itemValue,
           groupValue: currentValue,
+          enabled: enabled,
+          onChanged: onChanged
+        )
+      ])
+    );
+  }
+
+  Widget buildFontRadioItem(String label, TextStyle itemValue, TextStyle currentValue, ValueChanged<TextStyle> onChanged, { String icon, bool enabled: true }) {
+    return new DrawerItem(
+      icon: icon,
+      onPressed: enabled ? () { onChanged(itemValue); } : null,
+      child: new Row(<Widget>[
+        new Flexible(child: new Text(label)),
+        new Radio<TextStyle>(
+          value: itemValue,
+          groupValue: currentValue,
+          enabled: enabled,
           onChanged: onChanged
         )
       ])
@@ -238,9 +281,8 @@ class CardCollectionState extends State<CardCollection> {
         child: new Container(
           height: cardModel.height,
           padding: const EdgeDims.all(8.0),
-          child: new Center(
+          child: _editable ? 
-            child: new DefaultTextStyle(
+            new Center(
-              style: cardLabelStyle,
               child: new Input(
                 key: new GlobalObjectKey(cardModel),
                 initialValue: cardModel.label,
@@ -249,7 +291,15 @@ class CardCollectionState extends State<CardCollection> {
                 }
               )
             )
-          )
+          : new DefaultTextStyle(
+              style: DefaultTextStyle.of(context).merge(cardLabelStyle).merge(_textStyle),
+              child: new Column(<Widget>[
+                  new Text(cardModel.label)
+                ],
+                alignItems: FlexAlignItems.stretch,
+                justifyContent: FlexJustifyContent.center
+              )
+            )
         )
       )
     );

packages/flutter/lib/src/material/colors.dart

@@ -14,11 +14,11 @@ class Colors {
   static const black   = const Color(0xFF000000);
   static const black87 = const Color(0xDD000000);
   static const black54 = const Color(0x8A000000);
-  static const black26 = const Color(0x42000000); // text of disabled flat button in light theme
+  static const black26 = const Color(0x42000000); // disabled radio buttons and text of disabled flat buttons in light theme (26% black)
   static const black12 = const Color(0x1F000000); // background of disabled raised buttons in light theme
   static const white   = const Color(0xFFFFFFFF);
   static const white70 = const Color(0xB3FFFFFF);
-  static const white30 = const Color(0x4DFFFFFF); // text of disabled flat button in dark theme
+  static const white30 = const Color(0x4DFFFFFF); // disabled radio buttons and text of disabled flat buttons in dark theme (30% white)
   static const white12 = const Color(0x1FFFFFFF); // background of disabled raised buttons in dark theme
 
   static const Map<int, Color> red = const <int, Color>{

packages/flutter/lib/src/material/radio.dart

@@ -6,14 +6,13 @@ import 'dart:ui' as ui;
 
 import 'package:flutter/widgets.dart';
 
+import 'colors.dart';
 import 'theme.dart';
 
-const Color _kLightOffColor = const Color(0x8A000000);
-const Color _kDarkOffColor = const Color(0xB2FFFFFF);
-
 class Radio<T> extends StatelessComponent {
   Radio({
     Key key,
+    this.enabled,
     this.value,
     this.groupValue,
     this.onChanged
@@ -21,15 +20,18 @@ class Radio<T> extends StatelessComponent {
     assert(onChanged != null);
   }
 
+  final bool enabled;
   final T value;
   final T groupValue;
   final ValueChanged<T> onChanged;
 
   Color _getColor(BuildContext context) {
     ThemeData themeData = Theme.of(context);
+    if (!enabled)
+      return themeData.brightness == ThemeBrightness.light ? Colors.black26 : Colors.white30;
     if (value == groupValue)
       return themeData.accentColor;
-    return themeData.brightness == ThemeBrightness.light ? _kLightOffColor : _kDarkOffColor;
+    return themeData.brightness == ThemeBrightness.light ? Colors.black54 : Colors.white70;
   }
 
   Widget build(BuildContext context) {
@@ -37,7 +39,7 @@ class Radio<T> extends StatelessComponent {
     const double kOuterRadius = kDiameter / 2;
     const double kInnerRadius = 5.0;
     return new GestureDetector(
-      onTap: () => onChanged(value),
+      onTap: enabled ? () => onChanged(value) : null,
       child: new Container(
         margin: const EdgeDims.symmetric(horizontal: 5.0),
         width: kDiameter,
@@ -45,6 +47,8 @@ class Radio<T> extends StatelessComponent {
         child: new CustomPaint(
           onPaint: (Canvas canvas, Size size) {
 
+            // TODO(ianh): ink radial reaction
+
             // Draw the outer circle
             Paint paint = new Paint()
               ..color = _getColor(context)

packages/flutter/lib/src/widgets/gesture_detector.dart

@@ -243,4 +243,27 @@ class _GestureDetectorState extends State<GestureDetector> {
       child: config.child
     );
   }
+
+  void debugFillDescription(List<String> description) {
+    List<String> gestures = <String>[];
+    if (_tap != null)
+      gestures.add('tap');
+    if (_doubleTap != null)
+      gestures.add('double tap');
+    if (_showPress != null)
+      gestures.add('show press');
+    if (_longPress != null)
+      gestures.add('long press');
+    if (_verticalDrag != null)
+      gestures.add('vertical drag');
+    if (_horizontalDrag != null)
+      gestures.add('horizontal drag');
+    if (_pan != null)
+      gestures.add('pan');
+    if (_scale != null)
+      gestures.add('scale');
+    if (gestures.isEmpty);
+      gestures.add('<none>');
+    description.add('gestures: ${gestures.join(", ")}');
+  }
 }