Scaffold saves and restores scrollable state, etc

examples/material_gallery/lib/demo/dialog_demo.dart

@@ -14,11 +14,6 @@ enum DialogDemoAction {
   agree,
 }
 
-const String _introText =
-  "Use dialogs sparingly because their sudden appearance forces users to stop their "
-  "current task and focus on the dialog's content. Alternatives to dialogs include "
-  "menus or inline expansion, both of which maintain the current context.";
-
 const String _alertWithoutTitleText = "Discard draft?";
 
 const String _alertWithTitleText =
@@ -88,27 +83,11 @@ class DialogDemoState extends State<DialogDemo> {
       toolBar: new ToolBar(
         center: new Text('Dialogs')
       ),
-      body: new ButtonTheme(
-        color: ButtonColor.accent,
-        child: new Padding(
-          padding: const EdgeDims.all(24.0),
-          child: new ScrollableViewport(
-            child: new Column(
-              alignItems: FlexAlignItems.stretch,
+      body: new Block(
+        padding: const EdgeDims.symmetric(vertical: 24.0, horizontal: 72.0),
         children: <Widget>[
-                new Container(
-                  child: new Text(
-                    _introText,
-                    style: dialogTextStyle
-                  ),
-                  padding: const EdgeDims.only(top: 8.0, bottom: 24.0),
-                  margin: const EdgeDims.only(bottom:16.0),
-                  decoration: new BoxDecoration(
-                    border: new Border(bottom: new BorderSide(color: theme.dividerColor))
-                  )
-                ),
-                new FlatButton(
-                  child: new Text('Alert without a title'),
+          new RaisedButton(
+            child: new Text('ALERT'),
             onPressed: () {
               showDemoDialog(
                 context: context,
@@ -131,8 +110,8 @@ class DialogDemoState extends State<DialogDemo> {
               );
             }
           ),
-                new FlatButton(
-                  child: new Text('Alert with a title'),
+          new RaisedButton(
+            child: new Text('ALERT WITH TITLE'),
             onPressed: () {
               showDemoDialog(
                 context: context,
@@ -156,8 +135,8 @@ class DialogDemoState extends State<DialogDemo> {
               );
             }
           ),
-                new FlatButton(
-                  child: new Text('Simple Dialog'),
+          new RaisedButton(
+            child: new Text('SIMPLE'),
             onPressed: () {
               showDemoDialog(
                 context: context,
@@ -188,8 +167,8 @@ class DialogDemoState extends State<DialogDemo> {
               );
             }
           ),
-                new FlatButton(
-                  child: new Text('Confirmation Dialog'),
+          new RaisedButton(
+            child: new Text('CONFIRMATION'),
             onPressed: () {
               showTimePicker(
                 context: context,
@@ -204,8 +183,8 @@ class DialogDemoState extends State<DialogDemo> {
               });
             }
           ),
-                new FlatButton(
-                  child: new Text('Fullscreen Dialog'),
+          new RaisedButton(
+            child: new Text('FULLSCREEN'),
             onPressed: () {
               Navigator.push(context, new MaterialPageRoute(
                 builder: (BuildContext context) => new FullScreenDialogDemo()
@@ -214,9 +193,6 @@ class DialogDemoState extends State<DialogDemo> {
           )
         ]
       )
-          )
-        )
-      )
     );
   }
 }

examples/material_gallery/lib/demo/page_selector_demo.dart

@@ -5,17 +5,6 @@
 import 'package:flutter/material.dart';
 
 class PageSelectorDemo extends StatelessComponent {
-  Widget _buildTabView(IconData icon) {
-    return new Container(
-      key: new ObjectKey(icon),
-      padding: const EdgeDims.all(12.0),
-      child: new Card(
-        child: new Center(
-          child: new Icon(icon: icon, size: 48.0)
-        )
-      )
-    );
-  }
 
   void _handleArrowButtonPress(BuildContext context, int delta) {
     final TabBarSelectionState selection = TabBarSelection.of(context);
@@ -35,10 +24,11 @@ class PageSelectorDemo extends StatelessComponent {
 
     return new Scaffold(
       toolBar: new ToolBar(center: new Text('Page Selector')),
-      body: new TabBarSelection(
+      body: new TabBarSelection<IconData>(
         values: icons,
         child: new Builder(
           builder: (BuildContext context) {
+            final Color color = Theme.of(context).accentColor;
             return new Column(
               children: <Widget>[
                 new Container(
@@ -47,12 +37,14 @@ class PageSelectorDemo extends StatelessComponent {
                     children: <Widget>[
                       new IconButton(
                         icon: Icons.arrow_back,
+                        color: color,
                         onPressed: () { _handleArrowButtonPress(context, -1); },
                         tooltip: 'Back'
                       ),
-                      new TabPageSelector<String>(),
+                      new TabPageSelector<IconData>(),
                       new IconButton(
                         icon: Icons.arrow_forward,
+                        color: color,
                         onPressed: () { _handleArrowButtonPress(context, 1); },
                         tooltip: 'Forward'
                       )
@@ -62,7 +54,18 @@ class PageSelectorDemo extends StatelessComponent {
                 ),
                 new Flexible(
                   child: new TabBarView(
-                    children: icons.map(_buildTabView).toList()
+                    children: icons.map((IconData icon) {
+                      return new Container(
+                        key: new ObjectKey(icon),
+                        padding: const EdgeDims.all(12.0),
+                        child: new Card(
+                          child: new Center(
+                            child: new Icon(icon: icon, size: 128.0, color: color)
+                          )
+                        )
+                      );
+                    })
+                    .toList()
                   )
                 )
               ]

examples/material_gallery/lib/demo/tabs_demo.dart

@@ -23,7 +23,8 @@ class TabsDemo extends StatelessComponent {
     Icons.language: 'LANGUAGE',
   };
 
-  Widget build(_) {
+  Widget build(BuildContext context) {
+    final Color iconColor = Theme.of(context).accentColor;
     return new TabBarSelection(
       values: icons,
       child: new Scaffold(
@@ -43,7 +44,13 @@ class TabsDemo extends StatelessComponent {
               key: new ObjectKey(icon),
               padding: const EdgeDims.all(12.0),
               child: new Card(
-                child: new Center(child: new Icon(icon: icon, size: 48.0))
+                child: new Center(
+                  child: new Icon(
+                    icon: icon,
+                    color: iconColor,
+                    size: 128.0
+                  )
+                )
               )
             );
           }).toList()

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

@@ -345,6 +345,12 @@ class ScaffoldState extends State<Scaffold> {
   void initState() {
     super.initState();
     _appBarController = new AnimationController();
+    List<double> scrollValues = PageStorage.of(context)?.readState(context);
+    if (scrollValues != null) {
+      assert(scrollValues.length == 2);
+      _scrollOffset = scrollValues[0];
+      _scrollOffsetDelta = scrollValues[1];
+    }
   }
 
   void dispose() {
@@ -353,6 +359,7 @@ class ScaffoldState extends State<Scaffold> {
     _snackBarController = null;
     _snackBarTimer?.cancel();
     _snackBarTimer = null;
+    PageStorage.of(context)?.writeState(context, <double>[_scrollOffset, _scrollOffsetDelta]);
     super.dispose();
   }
 

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

@@ -999,7 +999,7 @@ class TabPageSelector<T> extends StatelessComponent {
 
   Widget build(BuildContext context) {
     final TabBarSelectionState selection = TabBarSelection.of(context);
-    final Color color = Theme.of(context).primaryColor;
+    final Color color = Theme.of(context).accentColor;
     final ColorTween selectedColor = new ColorTween(begin: Colors.transparent, end: color);
     final ColorTween previousColor = new ColorTween(begin: color, end: Colors.transparent);
     Animation<double> animation = new CurvedAnimation(parent: selection.animation, curve: Curves.ease);