Replace Flex to Row and Column in tests and examples.

This still leaves Flex and FlexDirection available. At some point once
people have transitioned to Row/Column we should rename Flex to _Flex
and stop reexporting FlexDirection from basic.dart.

examples/address_book/lib/main.dart

@@ -20,7 +20,7 @@ class Field extends Component {
   final String placeholder;
 
   Widget build() {
-    return new Flex([
+    return new Row([
         new Padding(
           padding: const EdgeDims.symmetric(horizontal: 16.0),
           child: new Icon(type: icon, size: 24)
@@ -31,8 +31,7 @@ class Field extends Component {
             placeholder: placeholder
           )
         )
-      ],
-      direction: FlexDirection.horizontal
+      ]
     );
   }
 }

examples/demo_launcher/lib/main.dart

@@ -148,14 +148,14 @@ class DemoList extends Component {
         child: new InkWell(
           child: new Container(
             margin: const EdgeDims.only(top: 24.0, left: 24.0),
-            child: new Flex([
-              new Text(demo.name, style: demo.textTheme.title),
-              new Flexible(
-                child: new Text(demo.description, style: demo.textTheme.subhead)
-              )
-            ],
-            direction: FlexDirection.vertical,
-            alignItems: FlexAlignItems.start)
+            child: new Column([
+                new Text(demo.name, style: demo.textTheme.title),
+                new Flexible(
+                  child: new Text(demo.description, style: demo.textTheme.subhead)
+                )
+              ],
+              alignItems: FlexAlignItems.start
+            )
           )
         )
     );

examples/fitness/lib/feed.dart

@@ -49,7 +49,7 @@ class DialogMenuItem extends ButtonBase {
         child: new InkWell(
           child: new Padding(
             padding: const EdgeDims.symmetric(horizontal: 16.0),
-            child: new Flex(children)
+            child: new Row(children)
           )
         )
       )
@@ -219,7 +219,7 @@ class FeedFragment extends StatefulComponent {
     if (userData.items.length == 0)
       return new Material(
         type: MaterialType.canvas,
-        child: new Flex(
+        child: new Row(
           [new Text("No data yet.\nAdd some!", style: style)],
           justifyContent: FlexJustifyContent.center
         )

examples/fitness/lib/meal.dart

@@ -34,7 +34,7 @@ class MealRow extends FitnessItemRow {
         )
       )
     ];
-    return new Flex(
+    return new Row(
       children,
       alignItems: FlexAlignItems.baseline,
       textBaseline: DefaultTextStyle.of(this).textBaseline

examples/fitness/lib/measurement.dart

@@ -45,7 +45,7 @@ class MeasurementRow extends FitnessItemRow {
         )
       )
     ];
-    return new Flex(
+    return new Row(
       children,
       alignItems: FlexAlignItems.baseline,
       textBaseline: DefaultTextStyle.of(this).textBaseline

examples/fitness/lib/settings.dart

@@ -104,18 +104,17 @@ class SettingsFragment extends StatefulComponent {
           child: new BlockBody([
             new DrawerItem(
               onPressed: () { _handleBackupChanged(!(userData.backupMode == BackupMode.enabled)); },
-              child: new Flex([
+              child: new Row([
                 new Flexible(child: new Text('Back up data to the cloud')),
                 new Switch(value: userData.backupMode == BackupMode.enabled, onChanged: _handleBackupChanged),
               ])
             ),
             new DrawerItem(
               onPressed: () => _handleGoalWeightPressed(),
-              child: new Flex([
+              child: new Column([
                   new Text('Goal Weight'),
                   new Text(goalWeightText, style: Theme.of(this).text.caption),
                 ],
-                direction: FlexDirection.vertical,
                 alignItems: FlexAlignItems.start
               )
             ),

examples/game/lib/main.dart

@@ -118,33 +118,33 @@ class GameDemoApp extends App {
   Widget _buildMainScene(navigator, route) {
     return new Stack([
       new SpriteWidget(new MainScreenBackground(), SpriteBoxTransformMode.fixedWidth),
-      new Flex([
-        new TextureButton(
-          onPressed: () {
-            _game = new GameDemoNode(
-              _imageMap,
-              _spriteSheet,
-              _spriteSheetUI,
-              _sounds,
-              (lastScore) {
-                setState(() {_lastScore = lastScore;});
-                navigator.pop();
-              }
-            );
-            navigator.pushNamed('/game');
-          },
-          texture: _spriteSheetUI['btn_play_up.png'],
-          textureDown: _spriteSheetUI['btn_play_down.png'],
-          width: 128.0,
-          height: 128.0
-        ),
-        new Text(
-          "Last Score: $_lastScore",
-          style: new TextStyle(fontSize:20.0)
-        )
-      ],
-      direction: FlexDirection.vertical,
-      justifyContent: FlexJustifyContent.center)
+      new Column([
+          new TextureButton(
+            onPressed: () {
+              _game = new GameDemoNode(
+                _imageMap,
+                _spriteSheet,
+                _spriteSheetUI,
+                _sounds,
+                (lastScore) {
+                  setState(() {_lastScore = lastScore;});
+                  navigator.pop();
+                }
+              );
+              navigator.pushNamed('/game');
+            },
+            texture: _spriteSheetUI['btn_play_up.png'],
+            textureDown: _spriteSheetUI['btn_play_down.png'],
+            width: 128.0,
+            height: 128.0
+          ),
+          new Text(
+            "Last Score: $_lastScore",
+            style: new TextStyle(fontSize:20.0)
+          )
+        ],
+        justifyContent: FlexJustifyContent.center
+      )
     ]);
   }
 }

examples/mine_digger/lib/main.dart

@@ -96,7 +96,7 @@ class MineDiggerApp extends App {
 
   Widget buildBoard() {
     bool hasCoveredCell = false;
-    List<Flex> flexRows = <Flex>[];
+    List<Row> flexRows = <Row>[];
     for (int iy = 0; iy != 9; iy++) {
       List<Widget> row = <Widget>[];
       for (int ix = 0; ix != 9; ix++) {
@@ -139,9 +139,8 @@ class MineDiggerApp extends App {
         }
       }
       flexRows.add(
-        new Flex(
+        new Row(
           row,
-          direction: FlexDirection.horizontal,
           justifyContent: FlexJustifyContent.center,
           key: new Key.stringify(iy)
         )
@@ -159,10 +158,7 @@ class MineDiggerApp extends App {
       padding: new EdgeDims.all(10.0),
       margin: new EdgeDims.all(10.0),
       decoration: new BoxDecoration(backgroundColor: const Color(0xFF6B6B6B)),
-      child: new Flex(
-        flexRows,
-        direction: FlexDirection.vertical
-      )
+      child: new Column(flexRows)
     );
   }
 

examples/rendering/borders.dart

@@ -7,68 +7,71 @@ import 'dart:sky' as sky;
 import 'package:sky/rendering.dart';
 
 void main() {
-  var root = new RenderBlock(children: [
-    new RenderPadding(
-      padding: new EdgeDims.all(10.0),
-      child: new RenderConstrainedBox(
-        additionalConstraints: new BoxConstraints.tightFor(height: 100.0),
-        child: new RenderDecoratedBox(
-          decoration: new BoxDecoration(
-            backgroundColor: new sky.Color(0xFFFFFF00)
+  var root = new RenderFlex(
+    children: [
+      new RenderPadding(
+        padding: new EdgeDims.all(10.0),
+        child: new RenderConstrainedBox(
+          additionalConstraints: new BoxConstraints.tightFor(height: 100.0),
+          child: new RenderDecoratedBox(
+            decoration: new BoxDecoration(
+              backgroundColor: new sky.Color(0xFFFFFF00)
+            )
           )
         )
-      )
-    ),
-    new RenderPadding(
-      padding: new EdgeDims.all(10.0),
-      child: new RenderConstrainedBox(
-        additionalConstraints: new BoxConstraints.tightFor(height: 100.0),
-        child: new RenderDecoratedBox(
-          decoration: new BoxDecoration(
-            border: new Border(
-              top: new BorderSide(color: new sky.Color(0xFFF00000), width: 5.0),
-              right: new BorderSide(color: new sky.Color(0xFFFF9000), width: 10.0),
-              bottom: new BorderSide(color: new sky.Color(0xFFFFF000), width: 15.0),
-              left: new BorderSide(color: new sky.Color(0xFF00FF00), width: 20.0)
-            ),
-            backgroundColor: new sky.Color(0xFFDDDDDD)
+      ),
+      new RenderPadding(
+        padding: new EdgeDims.all(10.0),
+        child: new RenderConstrainedBox(
+          additionalConstraints: new BoxConstraints.tightFor(height: 100.0),
+          child: new RenderDecoratedBox(
+            decoration: new BoxDecoration(
+              border: new Border(
+                top: new BorderSide(color: new sky.Color(0xFFF00000), width: 5.0),
+                right: new BorderSide(color: new sky.Color(0xFFFF9000), width: 10.0),
+                bottom: new BorderSide(color: new sky.Color(0xFFFFF000), width: 15.0),
+                left: new BorderSide(color: new sky.Color(0xFF00FF00), width: 20.0)
+              ),
+              backgroundColor: new sky.Color(0xFFDDDDDD)
+            )
           )
         )
-      )
-    ),
-    new RenderPadding(
-      padding: new EdgeDims.all(10.0),
-      child: new RenderConstrainedBox(
-        additionalConstraints: new BoxConstraints.tightFor(height: 100.0),
-        child: new RenderDecoratedBox(
-          decoration: new BoxDecoration(
-            backgroundColor: new sky.Color(0xFFFFFF00)
+      ),
+      new RenderPadding(
+        padding: new EdgeDims.all(10.0),
+        child: new RenderConstrainedBox(
+          additionalConstraints: new BoxConstraints.tightFor(height: 100.0),
+          child: new RenderDecoratedBox(
+            decoration: new BoxDecoration(
+              backgroundColor: new sky.Color(0xFFFFFF00)
+            )
           )
         )
-      )
-    ),
-    new RenderPadding(
-      padding: new EdgeDims.all(10.0),
-      child: new RenderConstrainedBox(
-        additionalConstraints: new BoxConstraints.tightFor(height: 100.0),
-        child: new RenderDecoratedBox(
-          decoration: new BoxDecoration(
-            backgroundColor: new sky.Color(0xFFFFFF00)
+      ),
+      new RenderPadding(
+        padding: new EdgeDims.all(10.0),
+        child: new RenderConstrainedBox(
+          additionalConstraints: new BoxConstraints.tightFor(height: 100.0),
+          child: new RenderDecoratedBox(
+            decoration: new BoxDecoration(
+              backgroundColor: new sky.Color(0xFFFFFF00)
+            )
           )
         )
-      )
-    ),
-    new RenderPadding(
-      padding: new EdgeDims.all(10.0),
-      child: new RenderConstrainedBox(
-        additionalConstraints: new BoxConstraints.tightFor(height: 100.0),
-        child: new RenderDecoratedBox(
-          decoration: new BoxDecoration(
-            backgroundColor: new sky.Color(0xFFFFFF00)
+      ),
+      new RenderPadding(
+        padding: new EdgeDims.all(10.0),
+        child: new RenderConstrainedBox(
+          additionalConstraints: new BoxConstraints.tightFor(height: 100.0),
+          child: new RenderDecoratedBox(
+            decoration: new BoxDecoration(
+              backgroundColor: new sky.Color(0xFFFFFF00)
+            )
           )
         )
-      )
-    ),
-  ]);
+      ),
+    ],
+    direction: FlexDirection.vertical
+  );
   new SkyBinding(root: root);
 }

examples/rendering/transform.dart

@@ -17,7 +17,9 @@ void main() {
 
   Matrix4 transform = new Matrix4.identity();
   RenderTransform spin = new RenderTransform(
-      transform: transform, child: box);
+    transform: transform,
+    child: box
+  );
   spin.rotateZ(1.0);
 
   RenderFlex flex = new RenderFlex();

examples/stocks/lib/stock_home.dart

@@ -136,7 +136,7 @@ class StockHome extends StatefulComponent {
         new DrawerItem(
           icon: 'action/thumb_up',
           onPressed: () => _handleStockModeChange(StockMode.optimistic),
-          child: new Flex([
+          child: new Row([
             new Flexible(child: new Text('Optimistic')),
             new Radio(value: StockMode.optimistic, groupValue: stockMode, onChanged: _handleStockModeChange)
           ])
@@ -144,7 +144,7 @@ class StockHome extends StatefulComponent {
         new DrawerItem(
           icon: 'action/thumb_down',
           onPressed: () => _handleStockModeChange(StockMode.pessimistic),
-          child: new Flex([
+          child: new Row([
             new Flexible(child: new Text('Pessimistic')),
             new Radio(value: StockMode.pessimistic, groupValue: stockMode, onChanged: _handleStockModeChange)
           ])

examples/stocks/lib/stock_menu.dart

@@ -33,7 +33,7 @@ class StockMenu extends Component {
           new PopupMenuItem(child: new Text('Remove stock')),
           new PopupMenuItem(
             onPressed: () => onAutorefreshChanged(!autorefresh),
-            child: new Flex([new Flexible(child: new Text('Autorefresh')), checkbox])
+            child: new Row([new Flexible(child: new Text('Autorefresh')), checkbox])
           ),
         ],
         level: 4,

examples/stocks/lib/stock_row.dart

@@ -46,13 +46,13 @@ class StockRow extends Component {
           bottom: new BorderSide(color: Theme.of(this).dividerColor)
         )
       ),
-      child: new Flex([
+      child: new Row([
         new Container(
           child: new StockArrow(percentChange: stock.percentChange),
           margin: const EdgeDims.only(right: 5.0)
         ),
         new Flexible(
-          child: new Flex(
+          child: new Row(
             children,
             alignItems: FlexAlignItems.baseline,
             textBaseline: DefaultTextStyle.of(this).textBaseline

examples/stocks/lib/stock_settings.dart

@@ -102,7 +102,7 @@ class StockSettings extends StatefulComponent {
             new DrawerItem(
               icon: 'action/thumb_up',
               onPressed: () => _confirmOptimismChange(),
-              child: new Flex([
+              child: new Row([
                 new Flexible(child: new Text('Everything is awesome')),
                 new Checkbox(value: optimism == StockMode.optimistic, onChanged: (_) => _confirmOptimismChange()),
               ])
@@ -110,7 +110,7 @@ class StockSettings extends StatefulComponent {
             new DrawerItem(
               icon: 'action/backup',
               onPressed: () { _handleBackupChanged(!(backup == BackupMode.enabled)); },
-              child: new Flex([
+              child: new Row([
                 new Flexible(child: new Text('Back up stock list to the cloud')),
                 new Switch(value: backup == BackupMode.enabled, onChanged: _handleBackupChanged),
               ])

examples/widgets/card_collection.dart

@@ -85,7 +85,7 @@ class CardCollectionApp extends App {
           child: new Container(
             height: cardModel.height,
             decoration: new BoxDecoration(backgroundColor: Theme.of(this).primaryColor),
-            child: new Flex([
+            child: new Row([
               new Icon(type: 'navigation/arrow_back', size: 36),
               new Flexible(child: backgroundText),
               new Icon(type: 'navigation/arrow_forward', size: 36)

examples/widgets/container.dart

@@ -6,7 +6,7 @@ import 'package:sky/widgets.dart';
 
 class ContainerApp extends App {
   Widget build() {
-    return new Flex([
+    return new Column([
         new Container(
           padding: new EdgeDims.all(10.0),
           margin: new EdgeDims.all(10.0),
@@ -20,7 +20,7 @@ class ContainerApp extends App {
         new Container(
           decoration: new BoxDecoration(backgroundColor: const Color(0xFFFFFF00)),
           padding: new EdgeDims.symmetric(horizontal: 50.0, vertical: 75.0),
-          child: new Flex([
+          child: new Row([
             new RaisedButton(
               child: new Text('PRESS ME'),
               onPressed: () => print("Hello World")
@@ -38,7 +38,6 @@ class ContainerApp extends App {
           )
         ),
       ],
-      direction: FlexDirection.vertical,
       justifyContent: FlexJustifyContent.spaceBetween
     );
   }

examples/widgets/drag_and_drop.dart

@@ -105,7 +105,7 @@ class DragAndDropApp extends App {
 
   Widget build() {
     List<Widget> layers = <Widget>[
-      new Flex([
+      new Row([
         new ExampleDragTarget(),
         new ExampleDragTarget(),
         new ExampleDragTarget(),

examples/widgets/horizontal_scrolling.dart

@@ -41,9 +41,11 @@ class HorizontalScrollingApp extends App {
     return new Center(
       child: new Container(
         height: 50.0,
-        child: new Flex([
-          new Block(circles, scrollDirection: ScrollDirection.horizontal)
-        ], justifyContent: FlexJustifyContent.end)
+        child: new Row([
+            new Block(circles, scrollDirection: ScrollDirection.horizontal)
+          ],
+          justifyContent: FlexJustifyContent.end
+        )
       )
     );
   }

examples/widgets/mixed_viewport.dart

@@ -57,10 +57,10 @@ class MixedViewportApp extends App {
             center: new Text('Block Viewport Demo')),
         body: new Material(
           type: MaterialType.canvas,
-          child: new Flex([
+          child: new Column([
               new Container(
                 padding: new EdgeDims.symmetric(horizontal: 8.0, vertical: 25.0),
-                child: new Flex([
+                child: new Row([
                     new RaisedButton(
                       enabled: enabledAdd,
                       child: new Text('ADD'),
@@ -96,7 +96,6 @@ class MixedViewportApp extends App {
                 )
               ),
             ],
-            direction: FlexDirection.vertical,
             justifyContent: FlexJustifyContent.spaceBetween
           )
         )

examples/widgets/navigation.dart

@@ -10,7 +10,7 @@ List<Route> routes = [
     builder: (navigator, route) => new Container(
       padding: const EdgeDims.all(30.0),
       decoration: new BoxDecoration(backgroundColor: const Color(0xFFCCCCCC)),
-      child: new Flex([
+      child: new Column([
         new Text("You are at home"),
         new RaisedButton(
           child: new Text('GO SHOPPING'),
@@ -20,7 +20,6 @@ List<Route> routes = [
           child: new Text('START ADVENTURE'),
           onPressed: () => navigator.pushNamed('adventure')
         )],
-        direction: FlexDirection.vertical,
         justifyContent: FlexJustifyContent.center
       )
     )
@@ -30,7 +29,7 @@ List<Route> routes = [
     builder: (navigator, route) => new Container(
       padding: const EdgeDims.all(20.0),
       decoration: new BoxDecoration(backgroundColor: const Color(0xFFBF5FFF)),
-      child: new Flex([
+      child: new Column([
         new Text("Village Shop"),
         new RaisedButton(
           child: new Text('RETURN HOME'),
@@ -40,7 +39,6 @@ List<Route> routes = [
           child: new Text('GO TO DUNGEON'),
           onPressed: () => navigator.push(routes[2])
         )],
-        direction: FlexDirection.vertical,
         justifyContent: FlexJustifyContent.center
       )
     )
@@ -50,13 +48,12 @@ List<Route> routes = [
     builder: (navigator, route) => new Container(
       padding: const EdgeDims.all(20.0),
       decoration: new BoxDecoration(backgroundColor: const Color(0xFFDC143C)),
-      child: new Flex([
+      child: new Column([
         new Text("Monster's Lair"),
         new RaisedButton(
           child: new Text('RUN!!!'),
           onPressed: () => navigator.pop()
         )],
-        direction: FlexDirection.vertical,
         justifyContent: FlexJustifyContent.center
       )
     )
@@ -77,7 +74,7 @@ class NavigationExampleApp extends App {
   }
 
   Widget build() {
-    return new Flex([new Navigator(_navState)]);
+    return new Row([new Navigator(_navState)]);
   }
 }
 

examples/widgets/piano.dart

@@ -88,10 +88,7 @@ class PianoApp extends App {
       );
     }
 
-    return new Flex(
-      children,
-      direction: FlexDirection.vertical
-    );
+    return new Column(children);
   }
 }
 

examples/widgets/progress_indicator.dart

@@ -64,11 +64,10 @@ class ProgressIndicatorApp extends App {
           child: new CircularProgressIndicator(value: valueAnimation.value)
         )
     ];
-    return new Flex(
+    return new Column(
       indicators
         .map((c) => new Container(child: c, margin: const EdgeDims.symmetric(vertical: 20.0)))
         .toList(),
-      direction: FlexDirection.vertical,
       justifyContent: FlexJustifyContent.center
     );
   }

examples/widgets/sector.dart

@@ -66,14 +66,14 @@ class SectorApp extends App {
   Widget buildBody() {
     return new Material(
       type: MaterialType.canvas,
-      child: new Flex([
+      child: new Column([
           new Container(
             padding: new EdgeDims.symmetric(horizontal: 8.0, vertical: 25.0),
-            child: new Flex([
+            child: new Row([
                 new RaisedButton(
                   enabled: enabledAdd,
                   child: new ShrinkWrapWidth(
-                    child: new Flex([
+                    child: new Row([
                       new Container(
                         padding: new EdgeDims.all(4.0),
                         margin: new EdgeDims.only(right: 10.0),
@@ -87,7 +87,7 @@ class SectorApp extends App {
                 new RaisedButton(
                   enabled: enabledRemove,
                   child: new ShrinkWrapWidth(
-                    child: new Flex([
+                    child: new Row([
                       new Container(
                         padding: new EdgeDims.all(4.0),
                         margin: new EdgeDims.only(right: 10.0),
@@ -113,7 +113,6 @@ class SectorApp extends App {
             )
           ),
         ],
-        direction: FlexDirection.vertical,
         justifyContent: FlexJustifyContent.spaceBetween
       )
     );

examples/widgets/spinning_mixed.dart

@@ -31,24 +31,26 @@ class Rectangle extends Component {
 }
 
 Widget builder() {
-  return new Flex([
-      new Rectangle(const Color(0xFF00FFFF)),
-      new Container(
-        padding: new EdgeDims.all(10.0),
-        margin: new EdgeDims.all(10.0),
-        decoration: new BoxDecoration(backgroundColor: const Color(0xFFCCCCCC)),
-        child: new RaisedButton(
-          child: new Flex([
-            new NetworkImage(src: "https://www.dartlang.org/logos/dart-logo.png"),
-            new Text('PRESS ME'),
-          ]),
-          onPressed: () => print("Hello World")
-        )
-      ),
-      new Rectangle(const Color(0xFFFFFF00)),
-    ],
-    direction: FlexDirection.vertical,
-    justifyContent: FlexJustifyContent.spaceBetween
+  return new Container(
+    height: 300.0,
+    child: new Column([
+        new Rectangle(const Color(0xFF00FFFF)),
+        new Container(
+          padding: new EdgeDims.all(10.0),
+          margin: new EdgeDims.all(10.0),
+          decoration: new BoxDecoration(backgroundColor: const Color(0xFFCCCCCC)),
+          child: new RaisedButton(
+            child: new Row([
+              new NetworkImage(src: "https://www.dartlang.org/logos/dart-logo.png"),
+              new Text('PRESS ME'),
+            ]),
+            onPressed: () => print("Hello World")
+          )
+        ),
+        new Rectangle(const Color(0xFFFFFF00)),
+      ],
+      justifyContent: FlexJustifyContent.spaceBetween
+    )
   );
 }
 
@@ -75,11 +77,10 @@ void main() {
   // want a renderViewOverride.
   WidgetSkyBinding.initWidgetSkyBinding();
 
-  RenderFlex flexRoot = new RenderFlex(direction: FlexDirection.vertical);
-
   RenderProxyBox proxy = new RenderProxyBox();
   new RenderBoxToWidgetAdapter(proxy, builder); // adds itself to proxy
 
+  RenderFlex flexRoot = new RenderFlex(direction: FlexDirection.vertical);
   addFlexChildSolidColor(flexRoot, const sky.Color(0xFFFF00FF), flex: 1);
   flexRoot.add(proxy);
   addFlexChildSolidColor(flexRoot, const sky.Color(0xFF0000FF), flex: 1);

examples/widgets/styled_text.dart

@@ -85,8 +85,7 @@ HAL: This mission is too important for me to allow you to jeopardize it.''';
 
     Container body = new Container(
         padding: new EdgeDims.symmetric(horizontal: 8.0),
-        child: new Flex(children,
-          direction: FlexDirection.vertical,
+        child: new Column(children,
           justifyContent: FlexJustifyContent.center,
           alignItems: FlexAlignItems.start
         )

packages/flutter/lib/editing/editable_text.dart

@@ -105,6 +105,6 @@ class EditableText extends StatefulComponent {
       child: new CustomPaint(callback: _paintCursor, token: _showCursor)
     );
 
-    return new Flex([text, cursor]);
+    return new Row([text, cursor]);
   }
 }

packages/flutter/lib/rendering/flex.dart

@@ -387,7 +387,7 @@ class RenderFlex extends RenderBox with ContainerRenderObjectMixin<RenderBox, Fl
           crossSize = math.max(crossSize, _getCrossSize(child));
         }
         if (alignItems == FlexAlignItems.baseline) {
-          assert(textBaseline != null);
+          assert(textBaseline != null && 'To use FlexAlignItems.baseline, you must also specify which baseline to use using the "baseline" argument.' is String);
           double distance = child.getDistanceToBaseline(textBaseline, onlyReal: true);
           if (distance != null)
             maxBaselineDistance = math.max(maxBaselineDistance, distance);

packages/flutter/lib/widgets/basic.dart

@@ -28,7 +28,7 @@ export 'package:sky/base/hit_test.dart' show EventDisposition, combineEventDispo
 export 'package:sky/painting/text_style.dart';
 export 'package:sky/rendering/block.dart' show BlockDirection;
 export 'package:sky/rendering/box.dart' show BoxConstraints;
-export 'package:sky/rendering/flex.dart' show FlexDirection, FlexJustifyContent, FlexAlignItems;
+export 'package:sky/rendering/flex.dart' show FlexJustifyContent, FlexAlignItems, FlexDirection;
 export 'package:sky/rendering/object.dart' show Point, Offset, Size, Rect, Color, Paint, Path;
 export 'package:sky/rendering/proxy_box.dart' show BackgroundImage, BoxDecoration, BoxDecorationPosition, BoxShadow, Border, BorderSide, EdgeDims, Shape;
 export 'package:sky/rendering/toggleable.dart' show ValueChanged;
@@ -494,7 +494,7 @@ class Row extends Flex {
     justifyContent: FlexJustifyContent.start,
     alignItems: FlexAlignItems.center,
     textBaseline
-  }) : super(children, key: key, direction: FlexDirection.horizontal, justifyContent: justifyContent, alignItems: alignItems);
+  }) : super(children, key: key, direction: FlexDirection.horizontal, justifyContent: justifyContent, alignItems: alignItems, textBaseline: textBaseline);
 }
 
 class Column extends Flex {
@@ -503,7 +503,7 @@ class Column extends Flex {
     justifyContent: FlexJustifyContent.start,
     alignItems: FlexAlignItems.center,
     textBaseline
-  }) : super(children, key: key, direction: FlexDirection.vertical, justifyContent: justifyContent, alignItems: alignItems);
+  }) : super(children, key: key, direction: FlexDirection.vertical, justifyContent: justifyContent, alignItems: alignItems, textBaseline: textBaseline);
 }
 
 class Flexible extends ParentDataNode {

packages/flutter/lib/widgets/framework.dart

@@ -16,7 +16,6 @@ import 'package:sky/rendering/view.dart';
 
 export 'package:sky/base/hit_test.dart' show EventDisposition, combineEventDispositions;
 export 'package:sky/rendering/box.dart' show BoxConstraints, BoxDecoration, Border, BorderSide, EdgeDims;
-export 'package:sky/rendering/flex.dart' show FlexDirection;
 export 'package:sky/rendering/object.dart' show Point, Offset, Size, Rect, Color, Paint, Path;
 
 final bool _shouldLogRenderDuration = false; // see also 'enableProfilingLoop' argument to runApp()