Now each Colors.foo constant is-a Color and a color swatch (#8833)

dev/manual_tests/card_collection.dart

@@ -32,7 +32,7 @@ class CardCollectionState extends State<CardCollection> {
   static const double kCardMargins = 8.0;
   static const double kFixedCardHeight = 100.0;
 
-  Map<int, Color> _primaryColor = Colors.deepPurple;
+  MaterialColor _primaryColor = Colors.deepPurple;
   List<CardModel> _cardModels;
   DismissDirection _dismissDirection = DismissDirection.horizontal;
   TextAlign _textAlign = TextAlign.center;
@@ -148,7 +148,7 @@ class CardCollectionState extends State<CardCollection> {
     });
   }
 
-  void _selectColor(Map<int, Color> selection) {
+  void _selectColor(MaterialColor selection) {
     setState(() {
       _primaryColor = selection;
     });
@@ -181,14 +181,14 @@ class CardCollectionState extends State<CardCollection> {
     );
   }
 
-  Widget buildDrawerColorRadioItem(String label, Map<int, Color> itemValue, Map<int, Color> currentValue, ValueChanged<Map<int, Color>> onChanged, { IconData icon, bool enabled: true }) {
+  Widget buildDrawerColorRadioItem(String label, MaterialColor itemValue, MaterialColor currentValue, ValueChanged<MaterialColor> onChanged, { IconData icon, bool enabled: true }) {
     return new DrawerItem(
       icon: new Icon(icon),
       onPressed: enabled ? () { onChanged(itemValue); } : null,
       child: new Row(
         children: <Widget>[
           new Expanded(child: new Text(label)),
-          new Radio<Map<int, Color>>(
+          new Radio<MaterialColor>(
             value: itemValue,
             groupValue: currentValue,
             onChanged: enabled ? onChanged : null,

examples/flutter_gallery/lib/demo/colors_demo.dart

@@ -6,37 +6,37 @@ import 'package:flutter/material.dart';
 
 const double kColorItemHeight = 48.0;
 
-class ColorSwatch {
-  ColorSwatch({ this.name, this.colors, this.accentColors, this.threshold: 900});
+class Palette {
+  Palette({ this.name, this.primary, this.accent, this.threshold: 900});
 
   final String name;
-  final Map<int, Color> colors;
-  final Map<int, Color> accentColors;
+  final MaterialColor primary;
+  final MaterialAccentColor accent;
   final int threshold; // titles for indices > threshold are white, otherwise black
 
-  bool get isValid => name != null && colors != null && threshold != null;
+  bool get isValid => name != null && primary != null && threshold != null;
 }
 
-final List<ColorSwatch> colorSwatches = <ColorSwatch>[
-  new ColorSwatch(name: 'RED', colors: Colors.red, accentColors: Colors.redAccent, threshold: 300),
-  new ColorSwatch(name: 'PINK', colors: Colors.pink, accentColors: Colors.pinkAccent, threshold: 200),
-  new ColorSwatch(name: 'PURPLE', colors: Colors.purple, accentColors: Colors.purpleAccent, threshold: 200),
-  new ColorSwatch(name: 'DEEP PURPLE', colors: Colors.deepPurple, accentColors: Colors.deepPurpleAccent, threshold: 200),
-  new ColorSwatch(name: 'INDIGO', colors: Colors.indigo, accentColors: Colors.indigoAccent, threshold: 200),
-  new ColorSwatch(name: 'BLUE', colors: Colors.blue, accentColors: Colors.blueAccent, threshold: 400),
-  new ColorSwatch(name: 'LIGHT BLUE', colors: Colors.lightBlue, accentColors: Colors.lightBlueAccent, threshold: 500),
-  new ColorSwatch(name: 'CYAN', colors: Colors.cyan, accentColors: Colors.cyanAccent, threshold: 600),
-  new ColorSwatch(name: 'TEAL', colors: Colors.teal, accentColors: Colors.tealAccent, threshold: 400),
-  new ColorSwatch(name: 'GREEN', colors: Colors.green, accentColors: Colors.greenAccent, threshold: 500),
-  new ColorSwatch(name: 'LIGHT GREEN', colors: Colors.lightGreen, accentColors: Colors.lightGreenAccent, threshold: 600),
-  new ColorSwatch(name: 'LIME', colors: Colors.lime, accentColors: Colors.limeAccent, threshold: 800),
-  new ColorSwatch(name: 'YELLOW', colors: Colors.yellow, accentColors: Colors.yellowAccent),
-  new ColorSwatch(name: 'AMBER', colors: Colors.amber, accentColors: Colors.amberAccent),
-  new ColorSwatch(name: 'ORANGE', colors: Colors.orange, accentColors: Colors.orangeAccent, threshold: 700),
-  new ColorSwatch(name: 'DEEP ORANGE', colors: Colors.deepOrange, accentColors: Colors.deepOrangeAccent, threshold: 400),
-  new ColorSwatch(name: 'BROWN', colors: Colors.brown, threshold: 200),
-  new ColorSwatch(name: 'GREY', colors: Colors.grey, threshold: 500),
-  new ColorSwatch(name: 'BLUE GREY', colors: Colors.blueGrey, threshold: 500),
+final List<Palette> allPalettes = <Palette>[
+  new Palette(name: 'RED', primary: Colors.red, accent: Colors.redAccent, threshold: 300),
+  new Palette(name: 'PINK', primary: Colors.pink, accent: Colors.pinkAccent, threshold: 200),
+  new Palette(name: 'PURPLE', primary: Colors.purple, accent: Colors.purpleAccent, threshold: 200),
+  new Palette(name: 'DEEP PURPLE', primary: Colors.deepPurple, accent: Colors.deepPurpleAccent, threshold: 200),
+  new Palette(name: 'INDIGO', primary: Colors.indigo, accent: Colors.indigoAccent, threshold: 200),
+  new Palette(name: 'BLUE', primary: Colors.blue, accent: Colors.blueAccent, threshold: 400),
+  new Palette(name: 'LIGHT BLUE', primary: Colors.lightBlue, accent: Colors.lightBlueAccent, threshold: 500),
+  new Palette(name: 'CYAN', primary: Colors.cyan, accent: Colors.cyanAccent, threshold: 600),
+  new Palette(name: 'TEAL', primary: Colors.teal, accent: Colors.tealAccent, threshold: 400),
+  new Palette(name: 'GREEN', primary: Colors.green, accent: Colors.greenAccent, threshold: 500),
+  new Palette(name: 'LIGHT GREEN', primary: Colors.lightGreen, accent: Colors.lightGreenAccent, threshold: 600),
+  new Palette(name: 'LIME', primary: Colors.lime, accent: Colors.limeAccent, threshold: 800),
+  new Palette(name: 'YELLOW', primary: Colors.yellow, accent: Colors.yellowAccent),
+  new Palette(name: 'AMBER', primary: Colors.amber, accent: Colors.amberAccent),
+  new Palette(name: 'ORANGE', primary: Colors.orange, accent: Colors.orangeAccent, threshold: 700),
+  new Palette(name: 'DEEP ORANGE', primary: Colors.deepOrange, accent: Colors.deepOrangeAccent, threshold: 400),
+  new Palette(name: 'BROWN', primary: Colors.brown, threshold: 200),
+  new Palette(name: 'GREY', primary: Colors.grey, threshold: 500),
+  new Palette(name: 'BLUE GREY', primary: Colors.blueGrey, threshold: 500),
 ];
 
 
@@ -71,29 +71,33 @@ class ColorItem extends StatelessWidget {
   }
 }
 
-class ColorSwatchTabView extends StatelessWidget {
-  ColorSwatchTabView({ Key key, this.swatch }) : super(key: key) {
-    assert(swatch != null && swatch.isValid);
+class PaletteTabView extends StatelessWidget {
+  static const List<int> primaryKeys = const <int>[50, 100, 200, 300, 400, 500, 600, 700, 800, 900];
+  static const List<int> accentKeys = const <int>[100, 200, 400, 700];
+
+  PaletteTabView({ Key key, this.colors }) : super(key: key) {
+    assert(colors != null && colors.isValid);
   }
 
-  final ColorSwatch swatch;
+  final Palette colors;
+
   @override
   Widget build(BuildContext context) {
     final TextTheme textTheme = Theme.of(context).textTheme;
     final TextStyle whiteTextStyle = textTheme.body1.copyWith(color: Colors.white);
     final TextStyle blackTextStyle = textTheme.body1.copyWith(color: Colors.black);
-    final List<Widget> colorItems =  swatch.colors.keys.map((int index) {
+    final List<Widget> colorItems =  primaryKeys.map((int index) {
       return new DefaultTextStyle(
-        style: index > swatch.threshold ? whiteTextStyle : blackTextStyle,
-        child: new ColorItem(index: index, color: swatch.colors[index]),
+        style: index > colors.threshold ? whiteTextStyle : blackTextStyle,
+        child: new ColorItem(index: index, color: colors.primary[index]),
       );
     }).toList();
 
-    if (swatch.accentColors != null) {
-      colorItems.addAll(swatch.accentColors.keys.map((int index) {
+    if (colors.accent != null) {
+      colorItems.addAll(accentKeys.map((int index) {
         return new DefaultTextStyle(
-          style: index > swatch.threshold ? whiteTextStyle : blackTextStyle,
-          child: new ColorItem(index: index, color: swatch.accentColors[index], prefix: 'A'),
+          style: index > colors.threshold ? whiteTextStyle : blackTextStyle,
+          child: new ColorItem(index: index, color: colors.accent[index], prefix: 'A'),
         );
       }).toList());
     }
@@ -111,19 +115,19 @@ class ColorsDemo extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     return new DefaultTabController(
-      length: colorSwatches.length,
+      length: allPalettes.length,
       child: new Scaffold(
         appBar: new AppBar(
           elevation: 0,
           title: new Text('Colors'),
           bottom: new TabBar(
             isScrollable: true,
-            tabs: colorSwatches.map((ColorSwatch swatch) => new Tab(text: swatch.name)).toList(),
+            tabs: allPalettes.map((Palette swatch) => new Tab(text: swatch.name)).toList(),
           ),
         ),
         body: new TabBarView(
-          children: colorSwatches.map((ColorSwatch swatch) {
-            return new ColorSwatchTabView(swatch: swatch);
+          children: allPalettes.map((Palette colors) {
+            return new PaletteTabView(colors: colors);
           }).toList(),
         ),
       ),

examples/flutter_gallery/lib/demo/material/icons_demo.dart

@@ -12,7 +12,7 @@ class IconsDemo extends StatefulWidget {
 }
 
 class IconsDemoState extends State<IconsDemo> {
-  static final List<Map<int, Color>> iconColorSwatches = <Map<int, Color>>[
+  static final List<MaterialColor> iconColors = <MaterialColor>[
     Colors.red,
     Colors.pink,
     Colors.purple,
@@ -31,17 +31,17 @@ class IconsDemoState extends State<IconsDemo> {
     Colors.deepOrange,
     Colors.brown,
     Colors.grey,
-    Colors.blueGrey
+    Colors.blueGrey,
   ];
 
   int iconColorIndex = 8; // teal
   double iconOpacity = 1.0;
 
-  Color get iconColor => iconColorSwatches[iconColorIndex][400];
+  Color get iconColor => iconColors[iconColorIndex];
 
   void handleIconButtonPress() {
     setState(() {
-      iconColorIndex = (iconColorIndex + 1) % iconColorSwatches.length;
+      iconColorIndex = (iconColorIndex + 1) % iconColors.length;
     });
   }
 

examples/flutter_gallery/lib/demo/material/tabs_fab_demo.dart

@@ -14,7 +14,7 @@ class _Page {
   _Page({ this.label, this.colors, this.icon });
 
   final String label;
-  final Map<int, Color> colors;
+  final MaterialColor colors;
   final IconData icon;
 
   Color get labelColor => colors != null ? colors[300] : Colors.grey[300];

examples/flutter_gallery/lib/gallery/drawer.dart

@@ -31,7 +31,7 @@ class GalleryDrawerHeader extends StatefulWidget {
 class _GalleryDrawerHeaderState extends State<GalleryDrawerHeader> {
   bool _logoHasName = true;
   bool _logoHorizontal = true;
-  Map<int, Color> _swatch = Colors.blue;
+  MaterialColor _logoColor = Colors.blue;
 
   @override
   Widget build(BuildContext context) {
@@ -43,7 +43,8 @@ class _GalleryDrawerHeaderState extends State<GalleryDrawerHeader> {
         style: _logoHasName ? _logoHorizontal ? FlutterLogoStyle.horizontal
                                               : FlutterLogoStyle.stacked
                                               : FlutterLogoStyle.markOnly,
-        swatch: _swatch,
+        lightColor: _logoColor.shade400,
+        darkColor: _logoColor.shade900,
         textColor: config.light ? const Color(0xFF616161) : const Color(0xFF9E9E9E),
       ),
       duration: const Duration(milliseconds: 750),
@@ -62,22 +63,22 @@ class _GalleryDrawerHeaderState extends State<GalleryDrawerHeader> {
         },
         onDoubleTap: () {
           setState(() {
-            final List<Map<int, Color>> options = <Map<int, Color>>[];
-            if (_swatch != Colors.blue)
-              options.addAll(<Map<int, Color>>[Colors.blue, Colors.blue, Colors.blue, Colors.blue, Colors.blue, Colors.blue, Colors.blue]);
-            if (_swatch != Colors.amber)
-              options.addAll(<Map<int, Color>>[Colors.amber, Colors.amber, Colors.amber]);
-            if (_swatch != Colors.red)
-              options.addAll(<Map<int, Color>>[Colors.red, Colors.red, Colors.red]);
-            if (_swatch != Colors.indigo)
-              options.addAll(<Map<int, Color>>[Colors.indigo, Colors.indigo, Colors.indigo]);
-            if (_swatch != Colors.pink)
-              options.addAll(<Map<int, Color>>[Colors.pink]);
-            if (_swatch != Colors.purple)
-              options.addAll(<Map<int, Color>>[Colors.purple]);
-            if (_swatch != Colors.cyan)
-              options.addAll(<Map<int, Color>>[Colors.cyan]);
-            _swatch = options[new math.Random().nextInt(options.length)];
+            final List<MaterialColor> options = <MaterialColor>[];
+            if (_logoColor != Colors.blue)
+              options.addAll(<MaterialColor>[Colors.blue, Colors.blue, Colors.blue, Colors.blue, Colors.blue, Colors.blue, Colors.blue]);
+            if (_logoColor != Colors.amber)
+              options.addAll(<MaterialColor>[Colors.amber, Colors.amber, Colors.amber]);
+            if (_logoColor != Colors.red)
+              options.addAll(<MaterialColor>[Colors.red, Colors.red, Colors.red]);
+            if (_logoColor != Colors.indigo)
+              options.addAll(<MaterialColor>[Colors.indigo, Colors.indigo, Colors.indigo]);
+            if (_logoColor != Colors.pink)
+              options.addAll(<MaterialColor>[Colors.pink]);
+            if (_logoColor != Colors.purple)
+              options.addAll(<MaterialColor>[Colors.purple]);
+            if (_logoColor != Colors.cyan)
+              options.addAll(<MaterialColor>[Colors.cyan]);
+            _logoColor = options[new math.Random().nextInt(options.length)];
           });
         }
       )

examples/layers/widgets/gestures.dart

@@ -18,7 +18,7 @@ class _GesturePainter extends CustomPainter {
 
   final double zoom;
   final Offset offset;
-  final Map<int, Color> swatch;
+  final MaterialColor swatch;
   final bool forward;
   final bool scaleEnabled;
   final bool tapEnabled;
@@ -71,7 +71,7 @@ class _GestureDemoState extends State<GestureDemo> {
   double _previousZoom;
   double _zoom = 1.0;
 
-  Map<int, Color> _swatch = Colors.blue;
+  MaterialColor _swatch = Colors.blue;
 
   bool _forward = true;
   bool _scaleEnabled = true;
@@ -106,28 +106,42 @@ class _GestureDemoState extends State<GestureDemo> {
 
   void _handleColorChange() {
     setState(() {
-      switch (_swatch) {
-        case Colors.blueGrey:   _swatch = Colors.red; break;
-        case Colors.red:        _swatch = Colors.pink; break;
-        case Colors.pink:       _swatch = Colors.purple; break;
-        case Colors.purple:     _swatch = Colors.deepPurple; break;
-        case Colors.deepPurple: _swatch = Colors.indigo; break;
-        case Colors.indigo:     _swatch = Colors.blue; break;
-        case Colors.blue:       _swatch = Colors.lightBlue; break;
-        case Colors.lightBlue:  _swatch = Colors.cyan; break;
-        case Colors.cyan:       _swatch = Colors.teal; break;
-        case Colors.teal:       _swatch = Colors.green; break;
-        case Colors.green:      _swatch = Colors.lightGreen; break;
-        case Colors.lightGreen: _swatch = Colors.lime; break;
-        case Colors.lime:       _swatch = Colors.yellow; break;
-        case Colors.yellow:     _swatch = Colors.amber; break;
-        case Colors.amber:      _swatch = Colors.orange; break;
-        case Colors.orange:     _swatch = Colors.deepOrange; break;
-        case Colors.deepOrange: _swatch = Colors.brown; break;
-        case Colors.brown:      _swatch = Colors.grey; break;
-        case Colors.grey:       _swatch = Colors.blueGrey; break;
-        default:                assert(false);
-      }
+      if (_swatch == Colors.blueGrey)
+        _swatch = Colors.red;
+      else if (_swatch == Colors.red)
+        _swatch = Colors.pink;
+      else if (_swatch == Colors.pink)
+        _swatch = Colors.purple;
+      else if (_swatch == Colors.purple)
+        _swatch = Colors.deepPurple;
+      else if (_swatch == Colors.deepPurple)
+        _swatch = Colors.indigo;
+      else if (_swatch == Colors.indigo)
+        _swatch = Colors.blue;
+      else if (_swatch == Colors.blue)
+        _swatch = Colors.lightBlue;
+      else if (_swatch == Colors.lightBlue)
+        _swatch = Colors.cyan;
+      else if (_swatch == Colors.teal)
+        _swatch = Colors.green;
+      else if (_swatch == Colors.green)
+        _swatch = Colors.lightGreen;
+      else if (_swatch == Colors.lightGreen)
+        _swatch = Colors.lime;
+      else if (_swatch == Colors.lime)
+        _swatch = Colors.yellow;
+      else if (_swatch == Colors.yellow)
+        _swatch = Colors.amber;
+      else if (_swatch == Colors.amber)
+        _swatch = Colors.orange;
+      else if (_swatch == Colors.orange)
+        _swatch = Colors.deepOrange;
+      else if (_swatch == Colors.deepOrange)
+        _swatch = Colors.brown;
+      else if (_swatch == Colors.brown)
+        _swatch = Colors.grey;
+      else if (_swatch == Colors.grey)
+        _swatch = Colors.blueGrey;
     });
   }
 

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

@@ -22,7 +22,7 @@ class FlutterLogo extends StatelessWidget {
   const FlutterLogo({
     Key key,
     this.size,
-    this.swatch: Colors.blue,
+    this.colors,
     this.textColor: const Color(0xFF616161),
     this.style: FlutterLogoStyle.markOnly,
     this.duration: const Duration(milliseconds: 750),
@@ -38,20 +38,16 @@ class FlutterLogo extends StatelessWidget {
   /// 24.0.
   final double size;
 
-  /// The colors to use to paint the logo. This map should contain at least two
-  /// values, one for 400 and one for 900.
+  /// The color swatch to use to paint the logo, Colors.blue by default.
   ///
-  /// If possible, the default should be used. It corresponds to the
-  /// [Colors.blue] swatch.
-  ///
-  /// If for some reason that color scheme is impractical, the [Colors.amber],
-  /// [Colors.red], or [Colors.indigo] swatches can be used. These are Flutter's
-  /// secondary colors.
+  /// If for some reason the default colors are impractical, then one
+  /// of [Colors.amber], [Colors.red], or [Colors.indigo] swatches can be used.
+  /// These are Flutter's secondary colors.
   ///
   /// In extreme cases where none of those four color schemes will work,
   /// [Colors.pink], [Colors.purple], or [Colors.cyan] swatches can be used.
   /// These are Flutter's tertiary colors.
-  final Map<int, Color> swatch;
+  final MaterialColor colors;
 
   /// The color used to paint the "Flutter" text on the logo, if [style] is
   /// [FlutterLogoStyle.horizontal] or [FlutterLogoStyle.stacked]. The
@@ -75,13 +71,15 @@ class FlutterLogo extends StatelessWidget {
   Widget build(BuildContext context) {
     final IconThemeData iconTheme = IconTheme.of(context);
     final double iconSize = size ?? iconTheme.size;
+    final MaterialColor logoColors = colors ?? Colors.blue;
     return new AnimatedContainer(
       width: iconSize,
       height: iconSize,
       duration: duration,
       curve: curve,
       decoration: new FlutterLogoDecoration(
-        swatch: swatch,
+        lightColor: logoColors.shade400,
+        darkColor: logoColors.shade900,
         style: style,
         textColor: textColor,
       ),

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

@@ -76,7 +76,7 @@ Map<MaterialListType, double> kListTileExtent = const <MaterialListType, double>
 ///  * [CircleAvatar], which shows an icon representing a person and is often
 ///    used as the [leading] element of a ListTile.
 ///  * [Divider], which can be used to separate [ListTile]s.
-///  * [ListTile.divideTiles], a utility for inserting [Divider]s in between [ListTiles]s.
+///  * [ListTile.divideTiles], a utility for inserting [Divider]s in between [ListTile]s.
 ///  * <https://material.google.com/components/lists.html>
 class ListTile extends StatelessWidget {
   /// Creates a list tile.

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

@@ -70,7 +70,7 @@ class ThemeData {
   /// more discussion on how to pick the right colors.
   factory ThemeData({
     Brightness brightness,
-    Map<int, Color> primarySwatch,
+    MaterialColor primarySwatch,
     Color primaryColor,
     Brightness primaryColorBrightness,
     Color accentColor,

packages/flutter/lib/src/painting/flutter_logo.dart

@@ -31,24 +31,19 @@ enum FlutterLogoStyle {
   stacked,
 }
 
-const int _lightShade = 400;
-const int _darkShade = 900;
-const Map<int, Color> _kDefaultSwatch = const <int, Color>{
-  _lightShade: const Color(0xFF42A5F5),
-  _darkShade: const Color(0xFF0D47A1)
-};
-
 /// An immutable description of how to paint Flutter's logo.
 class FlutterLogoDecoration extends Decoration {
   /// Creates a decoration that knows how to paint Flutter's logo.
   ///
-  /// The [swatch] controls the color used for the logo. The [style] controls
-  /// whether and where to draw the "Flutter" label. If one is shown, the
-  /// [textColor] controls the color of the label.
+  /// The [lightColor] and [darkColor] are used to fill the logo. The [style]
+  /// controls whether and where to draw the "Flutter" label. If one is shown,
+  /// the [textColor] controls the color of the label.
   ///
-  /// The [swatch], [textColor], and [style] arguments must not be null.
+  /// The [lightColor], [darkColor], [textColor], and [style] arguments must not
+  /// be null.
   const FlutterLogoDecoration({
-    this.swatch: _kDefaultSwatch,
+    this.lightColor: const Color(0xFF42A5F5), // Colors.blue[400]
+    this.darkColor: const Color(0xFF0D47A1), // Colors.blue[900]
     this.textColor: const Color(0xFF616161),
     this.style: FlutterLogoStyle.markOnly,
     this.margin: EdgeInsets.zero,
@@ -56,22 +51,26 @@ class FlutterLogoDecoration extends Decoration {
        // (see https://github.com/dart-lang/sdk/issues/26980 for details about that ignore statement)
        _opacity = 1.0;
 
-  FlutterLogoDecoration._(this.swatch, this.textColor, this.style, this._position, this._opacity, this.margin);
+  FlutterLogoDecoration._(this.lightColor, this.darkColor, this.textColor, this.style, this._position, this._opacity, this.margin);
 
-  /// The colors to use to paint the logo. This map should contain at least two
-  /// values, one for 400 and one for 900.
+  /// The lighter of the two colors used to paint the logo.
   ///
-  /// If possible, the default should be used. It corresponds to the
-  /// [Colors.blue] swatch from the Material library.
+  /// If possible, the default should be used. It corresponds to the 400 and 900
+  /// values of [Colors.blue] from the Material library.
   ///
-  /// If for some reason that color scheme is impractical, the [Colors.amber],
-  /// [Colors.red], or [Colors.indigo] swatches can be used. These are Flutter's
-  /// secondary colors.
+  /// If for some reason that color scheme is impractical, the same entries from
+  /// [Colors.amber], [Colors.red], or [Colors.indigo] colors can be used. These
+  /// are Flutter's secondary colors.
   ///
   /// In extreme cases where none of those four color schemes will work,
-  /// [Colors.pink], [Colors.purple], or [Colors.cyan] swatches can be used.
+  /// [Colors.pink], [Colors.purple], or [Colors.cyan] can be used.
   /// These are Flutter's tertiary colors.
-  final Map<int, Color> swatch;
+  final Color lightColor;
+
+  /// The darker of the two colors used to paint the logo.
+  ///
+  /// See [lightColor] for more information about selecting the logo's colors.
+  final Color darkColor;
 
   /// The color used to paint the "Flutter" text on the logo, if [style] is
   /// [FlutterLogoStyle.horizontal] or [FlutterLogoStyle.stacked]. The
@@ -97,9 +96,8 @@ class FlutterLogoDecoration extends Decoration {
 
   @override
   bool debugAssertIsValid() {
-    assert(swatch != null
-        && swatch[_lightShade] != null
-        && swatch[_darkShade] != null
+    assert(lightColor != null
+        && darkColor != null
         && textColor != null
         && style != null
         && _position != null
@@ -126,7 +124,8 @@ class FlutterLogoDecoration extends Decoration {
       return null;
     if (a == null) {
       return new FlutterLogoDecoration._(
-        b.swatch,
+        b.lightColor,
+        b.darkColor,
         b.textColor,
         b.style,
         b._position,
@@ -136,7 +135,8 @@ class FlutterLogoDecoration extends Decoration {
     }
     if (b == null) {
       return new FlutterLogoDecoration._(
-        a.swatch,
+        a.lightColor,
+        a.darkColor,
         a.textColor,
         a.style,
         a._position,
@@ -145,7 +145,8 @@ class FlutterLogoDecoration extends Decoration {
       );
     }
     return new FlutterLogoDecoration._(
-      _lerpSwatch(a.swatch, b.swatch, t),
+      Color.lerp(a.lightColor, b.lightColor, t),
+      Color.lerp(a.darkColor, b.darkColor, t),
       Color.lerp(a.textColor, b.textColor, t),
       t < 0.5 ? a.style : b.style,
       a._position + (b._position - a._position) * t,
@@ -154,15 +155,6 @@ class FlutterLogoDecoration extends Decoration {
     );
   }
 
-  static Map<int, Color> _lerpSwatch(Map<int, Color> a, Map<int, Color> b, double t) {
-    assert(a != null);
-    assert(b != null);
-    return <int, Color>{
-      _lightShade: Color.lerp(a[_lightShade], b[_lightShade], t),
-      _darkShade: Color.lerp(a[_darkShade], b[_darkShade], t),
-    };
-  }
-
   @override
   FlutterLogoDecoration lerpFrom(Decoration a, double t) {
     assert(debugAssertIsValid());
@@ -199,8 +191,8 @@ class FlutterLogoDecoration extends Decoration {
     if (other is! FlutterLogoDecoration)
       return false;
     final FlutterLogoDecoration typedOther = other;
-    return swatch[_lightShade] == typedOther.swatch[_lightShade]
-        && swatch[_darkShade] == typedOther.swatch[_darkShade]
+    return lightColor == typedOther.lightColor
+        && darkColor == typedOther.darkColor
         && textColor == typedOther.textColor
         && _position == typedOther._position
         && _opacity == typedOther._opacity;
@@ -210,8 +202,8 @@ class FlutterLogoDecoration extends Decoration {
   int get hashCode {
     assert(debugAssertIsValid());
     return hashValues(
-      swatch[_lightShade],
-      swatch[_darkShade],
+      lightColor,
+      darkColor,
       textColor,
       _position,
       _opacity
@@ -221,9 +213,7 @@ class FlutterLogoDecoration extends Decoration {
   @override
   String toString([String prefix = '', String prefixIndent ]) {
     final String extra = _inTransition ? ', transition $_position:$_opacity' : '';
-    if (swatch == null)
-      return '$prefix$runtimeType(null, $style$extra)';
-    return '$prefix$runtimeType(${swatch[_lightShade]}/${swatch[_darkShade]} on $textColor, $style$extra)';
+    return '$prefix$runtimeType($lightColor/$darkColor on $textColor, $style$extra)';
   }
 }
 
@@ -279,11 +269,11 @@ class _FlutterLogoPainter extends BoxPainter {
 
     // Set up the styles.
     final Paint lightPaint = new Paint()
-      ..color = _config.swatch[_lightShade].withOpacity(0.8);
+      ..color = _config.lightColor.withOpacity(0.8);
     final Paint mediumPaint = new Paint()
-      ..color = _config.swatch[_lightShade];
+      ..color = _config.lightColor;
     final Paint darkPaint = new Paint()
-      ..color = _config.swatch[_darkShade];
+      ..color = _config.darkColor;
 
     final ui.Gradient triangleGradient = new ui.Gradient.linear(
       const <Point>[

packages/flutter/test/material/colors_test.dart

+// Copyright 2017 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 'package:test/test.dart';
+
+import 'package:flutter/material.dart';
+
+const List<int> primaryKeys =  const <int>[50, 100, 200, 300, 400, 500, 600, 700, 800, 900];
+const List<int> accentKeys =  const <int>[100, 200, 400, 700];
+
+void main() {
+  test('MaterialColor basic functionality', () {
+    final MaterialColor color = new MaterialColor(
+      500,
+      const <int, Color>{
+         50: const Color(50),
+        100: const Color(100),
+        200: const Color(200),
+        300: const Color(300),
+        400: const Color(400),
+        500: const Color(500),
+        600: const Color(600),
+        700: const Color(700),
+        800: const Color(800),
+        900: const Color(900),
+      },
+    );
+
+    expect(color.value, 500);
+
+    expect(color[50].value, 50);
+    expect(color[100].value, 100);
+    expect(color[200].value, 200);
+    expect(color[300].value, 300);
+    expect(color[400].value, 400);
+    expect(color[500].value, 500);
+    expect(color[600].value, 600);
+    expect(color[700].value, 700);
+    expect(color[800].value, 800);
+    expect(color[900].value, 900);
+
+    expect(color.shade50.value, 50);
+    expect(color.shade100.value, 100);
+    expect(color.shade200.value, 200);
+    expect(color.shade300.value, 300);
+    expect(color.shade400.value, 400);
+    expect(color.shade500.value, 500);
+    expect(color.shade600.value, 600);
+    expect(color.shade700.value, 700);
+    expect(color.shade800.value, 800);
+    expect(color.shade900.value, 900);
+  });
+
+  test('Colors swatches do not contain duplicates', () {
+    for (MaterialColor color in Colors.primaries)
+      expect(primaryKeys.map((int key) => color[key]).toSet().length, primaryKeys.length);
+
+    expect(primaryKeys.map((int key) => Colors.grey[key]).toSet().length, primaryKeys.length);
+
+    for (MaterialAccentColor color in Colors.accents)
+      expect(accentKeys.map((int key) => color[key]).toSet().length, accentKeys.length);
+  });
+
+  test('All color swatch colors are opaque and equal their primary color', () {
+    for (MaterialColor color in Colors.primaries) {
+      expect(color.value, color.shade500.value);
+      for (int key in primaryKeys) {
+        expect(color[key].alpha, 0xFF);
+      }
+    }
+
+    expect(Colors.grey.value, Colors.grey.shade500.value);
+    for (int key in primaryKeys) {
+      expect(Colors.grey[key].alpha, 0xFF);
+    }
+
+    for (MaterialAccentColor color in Colors.accents) {
+      expect(color.value, color.shade200.value);
+      for (int key in accentKeys) {
+        expect(color[key].alpha, 0xFF);
+      }
+    }
+  });
+
+}