Adding Rally App to Flutter Samples (#135)

material_studies/rally/.gitignore

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+# Miscellaneous
+*.class
+*.log
+*.pyc
+*.swp
+.DS_Store
+.atom/
+.buildlog/
+.history
+.svn/
+
+# IntelliJ related
+*.iml
+*.ipr
+*.iws
+.idea/
+
+# Visual Studio Code related
+.vscode/
+
+# Flutter/Dart/Pub related
+**/doc/api/
+.dart_tool/
+.flutter-plugins
+.packages
+.pub-cache/
+.pub/
+/build/
+
+# Android related
+**/android/**/gradle-wrapper.jar
+**/android/.gradle
+**/android/captures/
+**/android/gradlew
+**/android/gradlew.bat
+**/android/local.properties
+**/android/**/GeneratedPluginRegistrant.java
+
+# iOS/XCode related
+**/ios/**/*.mode1v3
+**/ios/**/*.mode2v3
+**/ios/**/*.moved-aside
+**/ios/**/*.pbxuser
+**/ios/**/*.perspectivev3
+**/ios/**/*sync/
+**/ios/**/.sconsign.dblite
+**/ios/**/.tags*
+**/ios/**/.vagrant/
+**/ios/**/DerivedData/
+**/ios/**/Icon?
+**/ios/**/Pods/
+**/ios/**/.symlinks/
+**/ios/**/profile
+**/ios/**/xcuserdata
+**/ios/.generated/
+**/ios/Flutter/App.framework
+**/ios/Flutter/Flutter.framework
+**/ios/Flutter/Generated.xcconfig
+**/ios/Flutter/app.flx
+**/ios/Flutter/app.zip
+**/ios/Flutter/flutter_assets/
+**/ios/ServiceDefinitions.json
+**/ios/Runner/GeneratedPluginRegistrant.*
+
+# Exceptions to above rules.
+!**/ios/**/default.mode1v3
+!**/ios/**/default.mode2v3
+!**/ios/**/default.pbxuser
+!**/ios/**/default.perspectivev3
+!/packages/flutter_tools/test/data/dart_dependencies_test/**/.packages

material_studies/rally/README.md

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+# Rally
+
+A Flutter sample app based on the Material study Rally (a hypothetical, personal finance app). It
+showcases custom tabs, custom painted widgets, and custom animations.
+
+For info on the Rally Material Study, see: https://material.io/design/material-studies/rally.html
+
+## Goals
+
+* Show how to customize a tab bar.
+* Show how to create reusable custom widgets with composition and custom painting.
+* Show how to create an app with tabs and child navigation screens.
+
+## The important bits
+
+### `/charts/*`
+
+These are the custom charts. The circle chart and line chart are custom painters,
+while the single vertical bar chart is a simple composition of boxes.
+
+### `/sections/*`
+
+These are the main sections for the tab views and the child screen with the details and line chart.
+The financial entity is a reusable screen that is the base for the accounts, bills, and budgets
+screens.
+
+## Questions/issues
+
+If you have a general question about any of the techniques you see in
+the sample, the best places to go are:
+
+* [The FlutterDev Google Group](https://groups.google.com/forum/#!forum/flutter-dev)
+* [The Flutter Gitter channel](https://gitter.im/flutter/flutter)
+* [StackOverflow](https://stackoverflow.com/questions/tagged/flutter)
+
+If you run into an issue with the sample itself, please file an issue
+in the [main Flutter repo](https://github.com/flutter/flutter/issues).

material_studies/rally/analysis_options.yaml

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+include: package:pedantic/analysis_options.1.7.0.yaml
+
+analyzer:
+  strong-mode:
+    implicit-casts: false
+    implicit-dynamic: false
+
+linter:
+  rules:
+    - avoid_types_on_closure_parameters
+    - avoid_void_async
+    - await_only_futures
+    - camel_case_types
+    - cancel_subscriptions
+    - close_sinks
+    - constant_identifier_names
+    - control_flow_in_finally
+    - empty_statements
+    - hash_and_equals
+    - implementation_imports
+    - non_constant_identifier_names
+    - package_api_docs
+    - package_names
+    - package_prefixed_library_names
+    - test_types_in_equals
+    - throw_in_finally
+    - unnecessary_brace_in_string_interps
+    - unnecessary_getters_setters
+    - unnecessary_new
+    - unnecessary_statements

material_studies/rally/lib/app.dart

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+// Copyright 2019-present the Flutter authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
+
+import 'package:rally/colors.dart';
+import 'package:rally/home.dart';
+import 'package:rally/login.dart';
+
+/// The RallyApp is a MaterialApp with a theme and 2 routes.
+///
+/// The home route is the main page with tabs for sub pages.
+/// The login route is the initial route.
+class RallyApp extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      title: 'Rally',
+      theme: _buildRallyTheme(),
+      home: HomePage(),
+      initialRoute: '/login',
+      routes: {'/login': (context) => LoginPage()},
+    );
+  }
+
+  ThemeData _buildRallyTheme() {
+    final ThemeData base = ThemeData.dark();
+    return ThemeData(
+      scaffoldBackgroundColor: RallyColors.primaryBackground,
+      primaryColor: RallyColors.primaryBackground,
+      textTheme: _buildRallyTextTheme(base.textTheme),
+      inputDecorationTheme: InputDecorationTheme(
+        labelStyle:
+            TextStyle(color: RallyColors.gray, fontWeight: FontWeight.w500),
+        filled: true,
+        fillColor: RallyColors.inputBackground,
+        focusedBorder: InputBorder.none,
+      ),
+    );
+  }
+
+  TextTheme _buildRallyTextTheme(TextTheme base) {
+    return base
+        .copyWith(
+          body1: base.body1.copyWith(
+            fontFamily: 'Roboto Condensed',
+            fontSize: 14,
+            fontWeight: FontWeight.w400,
+          ),
+          body2: base.body2.copyWith(
+            fontFamily: 'Eczar',
+            fontSize: 40,
+            fontWeight: FontWeight.w400,
+            letterSpacing: 1.4,
+          ),
+          button: base.button.copyWith(
+            fontFamily: 'Roboto Condensed',
+            fontWeight: FontWeight.w700,
+            letterSpacing: 2.8,
+          ),
+          headline: base.body2.copyWith(
+            fontFamily: 'Eczar',
+            fontSize: 40,
+            fontWeight: FontWeight.w600,
+            letterSpacing: 1.4,
+          ),
+        )
+        .apply(
+          displayColor: Colors.white,
+          bodyColor: Colors.white,
+        );
+  }
+}

material_studies/rally/lib/charts/line_chart.dart

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+// Copyright 2019-present the Flutter authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'package:flutter/material.dart';
+import 'package:flutter/rendering.dart';
+import 'package:flutter/widgets.dart';
+
+import 'package:rally/colors.dart';
+import 'package:rally/data.dart';
+
+class RallyLineChart extends StatelessWidget {
+  RallyLineChart({this.events = const []}) : assert(events != null);
+
+  final List<DetailedEventData> events;
+
+  @override
+  Widget build(BuildContext context) {
+    return CustomPaint(painter: RallyLineChartPainter(context, events));
+  }
+}
+
+class RallyLineChartPainter extends CustomPainter {
+  RallyLineChartPainter(this.context, this.events);
+
+  final BuildContext context;
+
+  // Events to plot on the line as points.
+  final List<DetailedEventData> events;
+
+  // Number of days to plot.
+  // This is hardcoded to reflect the dummy data, but would be dynamic in a real
+  // app.
+  final int numDays = 52;
+
+  // Beginning of window. The end is this plus numDays.
+  // This is hardcoded to reflect the dummy data, but would be dynamic in a real
+  // app.
+  final DateTime startDate = DateTime.utc(2018, 12, 1);
+
+  // Ranges uses to lerp the pixel points.
+  // This is hardcoded to reflect the dummy data, but would be dynamic in a real
+  // app.
+  final double maxAmount = 3000.0; // minAmount is assumed to be 0.0
+
+  // The number of milliseconds in a day. This is the inherit period fot the
+  // points in this line.
+  static const int millisInDay = 24 * 60 * 60 * 1000;
+
+  // Amount to shift the tick drawing by so that the sunday ticks do not start
+  // on the edge.
+  final int tickShift = 3;
+
+  // Arbitrary unit of space for absolute positioned painting.
+  final double space = 16.0;
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    double ticksTop = size.height - space * 5;
+    double labelsTop = size.height - space * 2;
+    _drawLine(
+      canvas,
+      Rect.fromLTWH(0.0, 0.0, size.width, ticksTop),
+    );
+    _drawXAxisTicks(
+      canvas,
+      Rect.fromLTWH(0.0, ticksTop, size.width, labelsTop - ticksTop),
+    );
+    _drawXAxisLabels(
+      canvas,
+      Rect.fromLTWH(0.0, labelsTop, size.width, size.height - labelsTop),
+    );
+  }
+
+  @override
+  bool shouldRepaint(CustomPainter oldDelegate) {
+    return false;
+  }
+
+  void _drawLine(Canvas canvas, Rect rect) {
+    final linePaint = Paint()
+      ..color = RallyColors.accountColor(2)
+      ..style = PaintingStyle.stroke
+      ..strokeWidth = 2.0;
+
+    // Arbitrary value for the first point. In a real app, a wider range of
+    // points would be used that go beyond the boundaries of the screen.
+    double lastAmount = 800.0;
+
+    // Try changing this value between 1, 7, 15, etc.
+    int smoothing = 7;
+
+    // Align the points with equal deltas (1 day) as a cumulative sum.
+    int startMillis = startDate.millisecondsSinceEpoch;
+    final points = [
+      Offset(0.0, (maxAmount - lastAmount) / maxAmount * rect.height)
+    ];
+    for (int i = 0; i < numDays + smoothing; i++) {
+      int endMillis = startMillis + millisInDay * 1;
+      final filteredEvents = events.where((e) {
+        return startMillis <= e.date.millisecondsSinceEpoch &&
+            e.date.millisecondsSinceEpoch <= endMillis;
+      }).toList();
+      lastAmount += filteredEvents.fold<num>(0.0, (sum, e) => sum + e.amount);
+      double x = i / numDays * rect.width;
+      double y = (maxAmount - lastAmount) / maxAmount * rect.height;
+      points.add(Offset(x, y));
+      startMillis = endMillis;
+    }
+
+    final Path path = Path();
+    path.moveTo(points[0].dx, points[0].dy);
+    for (int i = 1; i < points.length - smoothing; i += smoothing) {
+      double x1 = points[i].dx;
+      double y1 = points[i].dy;
+      double x2 = (x1 + points[i + smoothing].dx) / 2;
+      double y2 = (y1 + points[i + smoothing].dy) / 2;
+      path.quadraticBezierTo(x1, y1, x2, y2);
+    }
+    canvas.drawPath(path, linePaint);
+  }
+
+  /// Draw the X-axis increment markers at constant width intervals.
+  void _drawXAxisTicks(Canvas canvas, Rect rect) {
+    double dayTop = (rect.top + rect.bottom) / 2;
+    for (int i = 0; i < numDays; i++) {
+      double x = rect.width / numDays * i;
+      canvas.drawRect(
+        Rect.fromPoints(
+          Offset(x, i % 7 == tickShift ? rect.top : dayTop),
+          Offset(x, rect.bottom),
+        ),
+        Paint()
+          ..style = PaintingStyle.stroke
+          ..strokeWidth = 1.0
+          ..color = RallyColors.gray25,
+      );
+    }
+  }
+
+  /// Set X-axis labels under the X-axis increment markers.
+  void _drawXAxisLabels(Canvas canvas, Rect rect) {
+    final selectedLabelStyle = Theme.of(context).textTheme.body1.copyWith(
+          fontWeight: FontWeight.w700,
+        );
+    final unselectedLabelStyle = Theme.of(context).textTheme.body1.copyWith(
+          fontWeight: FontWeight.w700,
+          color: RallyColors.gray25,
+        );
+
+    final leftLabel = TextPainter(
+      text: TextSpan(
+        text: 'AUGUST 2019',
+        style: unselectedLabelStyle,
+      ),
+      textDirection: TextDirection.ltr,
+    );
+    leftLabel.layout();
+    leftLabel.paint(canvas, Offset(rect.left + space / 2, rect.center.dy));
+
+    final centerLabel = TextPainter(
+      text: TextSpan(text: 'SEPTEMBER 2019', style: selectedLabelStyle),
+      textDirection: TextDirection.ltr,
+    );
+    centerLabel.layout();
+    final double x = (rect.width - centerLabel.width) / 2;
+    final double y = rect.center.dy;
+    centerLabel.paint(canvas, Offset(x, y));
+
+    final rightLabel = TextPainter(
+      text: TextSpan(
+        text: 'OCTOBER 2019',
+        style: unselectedLabelStyle,
+      ),
+      textDirection: TextDirection.ltr,
+    );
+    rightLabel.layout();
+    rightLabel.paint(
+      canvas,
+      Offset(rect.right - centerLabel.width - space / 2, rect.center.dy),
+    );
+  }
+}

material_studies/rally/lib/charts/pie_chart.dart

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+// Copyright 2019-present the Flutter authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'dart:math';
+
+import 'package:flutter/material.dart';
+import 'package:flutter/rendering.dart';
+import 'package:flutter/widgets.dart';
+
+import 'package:rally/colors.dart';
+import 'package:rally/data.dart';
+import 'package:rally/formatters.dart';
+
+/// A colored piece of the [RallyPieChart].
+class RallyPieChartSegment {
+  final Color color;
+  final double value;
+
+  const RallyPieChartSegment({this.color, this.value});
+}
+
+List<RallyPieChartSegment> buildSegmentsFromAccountItems(
+    List<AccountData> items) {
+  return List<RallyPieChartSegment>.generate(
+    items.length,
+    (i) => RallyPieChartSegment(
+      color: RallyColors.accountColor(i),
+      value: items[i].primaryAmount,
+    ),
+  );
+}
+
+List<RallyPieChartSegment> buildSegmentsFromBillItems(List<BillData> items) {
+  return List<RallyPieChartSegment>.generate(
+    items.length,
+    (i) => RallyPieChartSegment(
+      color: RallyColors.billColor(i),
+      value: items[i].primaryAmount,
+    ),
+  );
+}
+
+List<RallyPieChartSegment> buildSegmentsFromBudgetItems(
+    List<BudgetData> items) {
+  return List<RallyPieChartSegment>.generate(
+    items.length,
+    (i) => RallyPieChartSegment(
+      color: RallyColors.budgetColor(i),
+      value: items[i].primaryAmount - items[i].amountUsed,
+    ),
+  );
+}
+
+/// An animated circular pie chart to represent pieces of a whole, which can
+/// have empty space.
+class RallyPieChart extends StatefulWidget {
+  RallyPieChart(
+      {this.heroLabel, this.heroAmount, this.wholeAmount, this.segments});
+
+  final String heroLabel;
+  final double heroAmount;
+  final double wholeAmount;
+  final List<RallyPieChartSegment> segments;
+
+  _RallyPieChartState createState() => _RallyPieChartState();
+}
+
+class _RallyPieChartState extends State<RallyPieChart>
+    with SingleTickerProviderStateMixin {
+  AnimationController controller;
+  Animation<double> animation;
+
+  @override
+  initState() {
+    super.initState();
+    controller = AnimationController(
+        duration: const Duration(milliseconds: 600), vsync: this);
+    animation = CurvedAnimation(
+        parent: TweenSequence(<TweenSequenceItem<double>>[
+          TweenSequenceItem(tween: Tween(begin: 0.0, end: 0.0), weight: 1.0),
+          TweenSequenceItem(tween: Tween(begin: 0.0, end: 1.0), weight: 1.5),
+        ]).animate(controller),
+        curve: Curves.decelerate);
+    controller.forward();
+  }
+
+  dispose() {
+    controller.dispose();
+    super.dispose();
+  }
+
+  Widget build(BuildContext context) {
+    return _AnimatedRallyPieChart(
+      animation: animation,
+      centerLabel: widget.heroLabel,
+      centerAmount: widget.heroAmount,
+      total: widget.wholeAmount,
+      segments: widget.segments,
+    );
+  }
+}
+
+class _AnimatedRallyPieChart extends AnimatedWidget {
+  _AnimatedRallyPieChart({
+    Key key,
+    this.animation,
+    this.centerLabel,
+    this.centerAmount,
+    this.total,
+    this.segments,
+  }) : super(key: key, listenable: animation);
+
+  final Animation<double> animation;
+  final String centerLabel;
+  final double centerAmount;
+  final double total;
+  final List<RallyPieChartSegment> segments;
+
+  Widget build(BuildContext context) {
+    final labelTextStyle = Theme.of(context)
+        .textTheme
+        .body1
+        .copyWith(fontSize: 14.0, letterSpacing: 0.5);
+
+    return DecoratedBox(
+      decoration: _RallyPieChartOutlineDecoration(
+          maxFraction: animation.value, total: total, segments: segments),
+      child: SizedBox(
+        height: 300.0,
+        child: Center(
+          child: Column(
+            mainAxisAlignment: MainAxisAlignment.center,
+            children: [
+              Text(
+                centerLabel,
+                style: labelTextStyle,
+              ),
+              Text(
+                Formatters.usdWithSign.format(centerAmount),
+                style: Theme.of(context).textTheme.headline,
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}
+
+class _RallyPieChartOutlineDecoration extends Decoration {
+  _RallyPieChartOutlineDecoration(
+      {this.maxFraction, this.total, this.segments});
+
+  final double maxFraction;
+  final double total;
+  final List<RallyPieChartSegment> segments;
+
+  @override
+  BoxPainter createBoxPainter([onChanged]) {
+    return _RallyPieChartOutlineBoxPainter(
+      maxFraction: maxFraction,
+      wholeAmount: total,
+      segments: segments,
+    );
+  }
+}
+
+class _RallyPieChartOutlineBoxPainter extends BoxPainter {
+  _RallyPieChartOutlineBoxPainter(
+      {this.maxFraction, this.wholeAmount, this.segments});
+
+  final double maxFraction;
+  final double wholeAmount;
+  final List<RallyPieChartSegment> segments;
+
+  @override
+  void paint(Canvas canvas, Offset offset, ImageConfiguration configuration) {
+    // Create two padded rects to draw arcs in: one for colored arcs and one for
+    // inner bg arc.
+    const double strokeWidth = 4.0;
+    final outerRadius =
+        min(configuration.size.width, configuration.size.height) / 2;
+    final outerRect = Rect.fromCircle(
+        center: configuration.size.center(Offset.zero),
+        radius: outerRadius - strokeWidth * 3.0);
+    final innerRect = Rect.fromCircle(
+        center: configuration.size.center(Offset.zero),
+        radius: outerRadius - strokeWidth * 4.0);
+
+    // Paint each arc with spacing.
+    double cummulativeSpace = 0.0;
+    double cummulativeTotal = 0.0;
+    const double wholeRadians = (2.0 * pi);
+    const double spaceRadians = wholeRadians / 180.0;
+    final wholeMinusSpacesRadians =
+        wholeRadians - (segments.length * spaceRadians);
+    for (RallyPieChartSegment segment in segments) {
+      final paint = Paint()..color = segment.color;
+      final start = maxFraction *
+              ((cummulativeTotal / wholeAmount * wholeMinusSpacesRadians) +
+                  cummulativeSpace) -
+          pi / 2.0;
+      final sweep =
+          maxFraction * (segment.value / wholeAmount * wholeMinusSpacesRadians);
+      canvas.drawArc(outerRect, start, sweep, true, paint);
+      cummulativeTotal += segment.value;
+      cummulativeSpace += spaceRadians;
+    }
+
+    // Paint any remaining space black (e.g. budget amount remaining).
+    double remaining = wholeAmount - cummulativeTotal;
+    if (remaining > 0) {
+      final paint = Paint()..color = Colors.black;
+      final start = maxFraction *
+              ((cummulativeTotal / wholeAmount * wholeMinusSpacesRadians) +
+                  spaceRadians * segments.length) -
+          pi / 2.0;
+      final sweep = maxFraction *
+          (remaining / wholeAmount * wholeMinusSpacesRadians - spaceRadians);
+      canvas.drawArc(outerRect, start, sweep, true, paint);
+    }
+
+    // Paint a smaller inner circle to cover the painted arcs, so they are
+    // display as segments.
+    Paint bgPaint = Paint()..color = RallyColors.primaryBackground;
+    canvas.drawArc(innerRect, 0.0, 2.0 * pi, true, bgPaint);
+  }
+}

material_studies/rally/lib/charts/vertical_fraction_bar.dart

@@ -0,0 +1,45 @@
+// Copyright 2019-present the Flutter authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
+
+class VerticalFractionBar extends StatelessWidget {
+  VerticalFractionBar({this.color, this.fraction});
+
+  final Color color;
+  final double fraction;
+
+  @override
+  Widget build(BuildContext context) {
+    return SizedBox(
+      height: 32.0,
+      width: 4.0,
+      child: Column(
+        children: [
+          SizedBox(
+            height: (1 - fraction) * 32.0,
+            child: Container(
+              color: Colors.black,
+            ),
+          ),
+          SizedBox(
+            height: fraction * 32.0,
+            child: Container(color: color),
+          ),
+        ],
+      ),
+    );
+  }
+}

material_studies/rally/lib/colors.dart

@@ -0,0 +1,69 @@
+// Copyright 2019-present the Flutter authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'package:flutter/material.dart';
+
+/// Most color assignments in Rally are not like the the typical color
+/// assignments that are common in other apps. Instead of primarily mapping to
+/// component type and part, they are assigned round robin based on layout.
+class RallyColors {
+  static const accountColors = [
+    Color(0xFF005D57),
+    Color(0xFF04B97F),
+    Color(0xFF37EFBA),
+    Color(0xFF007D51),
+  ];
+
+  static const billColors = [
+    Color(0xFFFFDC78),
+    Color(0xFFFF6951),
+    Color(0xFFFFD7D0),
+    Color(0xFFFFAC12),
+  ];
+
+  static const budgetColors = [
+    Color(0xFFB2F2FF),
+    Color(0xFFB15DFF),
+    Color(0xFF72DEFF),
+    Color(0xFF0082FB),
+  ];
+
+  static const gray = Color(0xFFD8D8D8);
+  static const gray60 = Color(0x99D8D8D8);
+  static const gray25 = Color(0x40D8D8D8);
+  static const white60 = Color(0x99FFFFFF);
+  static const primaryBackground = Color(0xFF33333D);
+  static const inputBackground = Color(0xFF26282F);
+  static const cardBackground = Color(0x03FEFEFE);
+
+  /// Convenience method to get a single account color with position i.
+  static Color accountColor(int i) {
+    return cycledColor(accountColors, i);
+  }
+
+  /// Convenience method to get a single bill color with position i.
+  static Color billColor(int i) {
+    return cycledColor(billColors, i);
+  }
+
+  /// Convenience method to get a single budget color with position i.
+  static Color budgetColor(int i) {
+    return cycledColor(budgetColors, i);
+  }
+
+  /// Gets a color from a list that is considered to be infinitely repeating.
+  static Color cycledColor(List<Color> colors, int i) {
+    return colors[i % colors.length];
+  }
+}

material_studies/rally/lib/data.dart

@@ -0,0 +1,223 @@
+// Copyright 2019-present the Flutter authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/// Calculates the sum of the primary amounts of a list of [AccountData].
+double sumAccountDataPrimaryAmount(List<AccountData> items) {
+  return items.fold(
+    0,
+    (sum, next) => sum + next.primaryAmount,
+  );
+}
+
+/// Calculates the sum of the primary amounts of a list of [BillData].
+double sumBillDataPrimaryAmount(List<BillData> items) {
+  return items.fold(
+    0,
+    (sum, next) => sum + next.primaryAmount,
+  );
+}
+
+/// Calculates the sum of the primary amounts of a list of [BudgetData].
+double sumBudgetDataPrimaryAmount(List<BudgetData> items) {
+  return items.fold(
+    0,
+    (sum, next) => sum + next.primaryAmount,
+  );
+}
+
+/// Calculates the sum of the amounts used of a list of [BudgetData].
+double sumBudgetDataAmountUsed(List<BudgetData> items) {
+  return items.fold(
+    0.0,
+    (sum, next) => sum + next.amountUsed,
+  );
+}
+
+/// A data model for an account.
+///
+/// The [primaryAmount] is the balance of the account in USD.
+class AccountData {
+  const AccountData({this.name, this.primaryAmount, this.accountNumber});
+
+  /// The display name of this entity.
+  final String name;
+
+  // The primary amount or value of this entity.
+  final double primaryAmount;
+
+  /// The full displayable account number.
+  final String accountNumber;
+}
+
+/// A data model for a bill.
+///
+/// The [primaryAmount] is the amount due in USD.
+class BillData {
+  const BillData({this.name, this.primaryAmount, this.dueDate});
+
+  /// The display name of this entity.
+  final String name;
+
+  // The primary amount or value of this entity.
+  final double primaryAmount;
+
+  /// The due date of this bill.
+  final String dueDate;
+}
+
+/// A data model for a budget.
+///
+/// The [primaryAmount] is the budget cap in USD.
+class BudgetData {
+  const BudgetData({this.name, this.primaryAmount, this.amountUsed});
+
+  /// The display name of this entity.
+  final String name;
+
+  // The primary amount or value of this entity.
+  final double primaryAmount;
+
+  /// Amount of the budget that is consumed or used.
+  final double amountUsed;
+}
+
+class DetailedEventData {
+  const DetailedEventData({
+    this.title,
+    this.date,
+    this.amount,
+  });
+
+  final String title;
+  final DateTime date;
+  final double amount;
+}
+
+/// Class to return dummy data lists.
+///
+/// In a real app, this might be replaced with some asynchronous service.
+class DummyDataService {
+  static List<AccountData> getAccountDataList() {
+    return [
+      AccountData(
+        name: 'Checking',
+        primaryAmount: 2215.13,
+        accountNumber: '1234561234',
+      ),
+      AccountData(
+        name: 'Home Savings',
+        primaryAmount: 8678.88,
+        accountNumber: '8888885678',
+      ),
+      AccountData(
+        name: 'Car Savings',
+        primaryAmount: 987.48,
+        accountNumber: '8888889012',
+      ),
+      AccountData(
+        name: 'Vacation',
+        primaryAmount: 253.0,
+        accountNumber: '1231233456',
+      ),
+    ];
+  }
+
+  static List<DetailedEventData> getDetailedEventItems() {
+    return [
+      DetailedEventData(
+          title: 'Genoe', date: DateTime.utc(2019, 1, 24), amount: -16.54),
+      DetailedEventData(
+          title: 'Fortnightly Subscribe',
+          date: DateTime.utc(2019, 1, 5),
+          amount: -12.54),
+      DetailedEventData(
+          title: 'Circle Cash', date: DateTime.utc(2019, 1, 5), amount: 365.65),
+      DetailedEventData(
+          title: 'Crane Hospitality',
+          date: DateTime.utc(2019, 1, 4),
+          amount: -705.13),
+      DetailedEventData(
+          title: 'ABC Payroll',
+          date: DateTime.utc(2018, 12, 15),
+          amount: 1141.43),
+      DetailedEventData(
+          title: 'Shrine', date: DateTime.utc(2018, 12, 15), amount: -88.88),
+      DetailedEventData(
+          title: 'Foodmates', date: DateTime.utc(2018, 12, 4), amount: -11.69),
+    ];
+  }
+
+  static List<BillData> getBillDataList() {
+    return [
+      BillData(
+        name: 'RedPay Credit',
+        primaryAmount: 45.36,
+        dueDate: 'Jan 29',
+      ),
+      BillData(
+        name: 'Rent',
+        primaryAmount: 1200.0,
+        dueDate: 'Feb 9',
+      ),
+      BillData(
+        name: 'TabFine Credit',
+        primaryAmount: 87.33,
+        dueDate: 'Feb 22',
+      ),
+      BillData(
+        name: 'ABC Loans',
+        primaryAmount: 400.0,
+        dueDate: 'Feb 29',
+      ),
+    ];
+  }
+
+  static List<BudgetData> getBudgetDataList() {
+    return [
+      BudgetData(
+        name: 'Coffee Shops',
+        primaryAmount: 70.0,
+        amountUsed: 45.49,
+      ),
+      BudgetData(
+        name: 'Groceries',
+        primaryAmount: 170.0,
+        amountUsed: 16.45,
+      ),
+      BudgetData(
+        name: 'Restaurants',
+        primaryAmount: 170.0,
+        amountUsed: 123.25,
+      ),
+      BudgetData(
+        name: 'Clothing',
+        primaryAmount: 70.0,
+        amountUsed: 19.45,
+      ),
+    ];
+  }
+
+  static List<String> getSettingsTitles() {
+    return [
+      'Manage Accounts',
+      'Tax Documents',
+      'Passcode and Touch ID',
+      'Notifications',
+      'Personal Information',
+      'Paperless Settings',
+      'Find ATMs',
+      'Help',
+    ];
+  }
+}

material_studies/rally/lib/finance.dart

@@ -0,0 +1,344 @@
+// Copyright 2019-present the Flutter authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
+
+import 'package:rally/charts/pie_chart.dart';
+import 'package:rally/charts/line_chart.dart';
+import 'package:rally/charts/vertical_fraction_bar.dart';
+import 'package:rally/colors.dart';
+import 'package:rally/data.dart';
+import 'package:rally/formatters.dart';
+
+class FinancialEntityView extends StatelessWidget {
+  FinancialEntityView({
+    this.heroLabel,
+    this.heroAmount,
+    this.wholeAmount,
+    this.segments,
+    this.financialEntityCards,
+  }) : assert(segments.length == financialEntityCards.length);
+
+  /// The amounts to assign each item.
+  ///
+  /// This list must have the same length as [colors].
+  final List<RallyPieChartSegment> segments;
+  final String heroLabel;
+  final double heroAmount;
+  final double wholeAmount;
+  final List<FinancialEntityCategoryView> financialEntityCards;
+
+  @override
+  Widget build(BuildContext context) {
+    return Column(
+      children: [
+        RallyPieChart(
+          heroLabel: heroLabel,
+          heroAmount: heroAmount,
+          wholeAmount: wholeAmount,
+          segments: segments,
+        ),
+        SizedBox(
+          height: 1.0,
+          child: Container(
+            color: Color(0xA026282F),
+          ),
+        ),
+        ListView(shrinkWrap: true, children: financialEntityCards)
+      ],
+    );
+  }
+}
+
+/// A reusable widget to show balance information of a single entity as a card.
+class FinancialEntityCategoryView extends StatelessWidget {
+  const FinancialEntityCategoryView({
+    @required this.indicatorColor,
+    @required this.indicatorFraction,
+    @required this.title,
+    @required this.subtitle,
+    @required this.amount,
+    @required this.suffix,
+  });
+
+  final Color indicatorColor;
+  final double indicatorFraction;
+  final String title;
+  final String subtitle;
+  final double amount;
+  final Widget suffix;
+
+  @override
+  Widget build(BuildContext context) {
+    return FlatButton(
+      onPressed: () {
+        Navigator.push(
+          context,
+          MaterialPageRoute<FinancialEntityCategoryDetailsPage>(
+            builder: (context) => FinancialEntityCategoryDetailsPage(),
+          ),
+        );
+      },
+      child: SizedBox(
+        height: 68,
+        child: Column(
+          children: [
+            Expanded(
+              child: Row(
+                children: [
+                  Padding(
+                    padding: EdgeInsets.only(left: 12, right: 12),
+                    child: VerticalFractionBar(
+                      color: indicatorColor,
+                      fraction: indicatorFraction,
+                    ),
+                  ),
+                  Column(
+                    mainAxisAlignment: MainAxisAlignment.center,
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      Text(
+                        title,
+                        style: Theme.of(context)
+                            .textTheme
+                            .body1
+                            .copyWith(fontSize: 16.0),
+                      ),
+                      Text(
+                        subtitle,
+                        style: Theme.of(context)
+                            .textTheme
+                            .body1
+                            .copyWith(color: RallyColors.gray60),
+                      ),
+                    ],
+                  ),
+                  Spacer(),
+                  Text(
+                    '\$ ' + Formatters.usd.format(amount),
+                    style: Theme.of(context)
+                        .textTheme
+                        .body2
+                        .copyWith(fontSize: 20.0, color: RallyColors.gray),
+                  ),
+                  SizedBox(width: 32.0, child: suffix),
+                ],
+              ),
+            ),
+            Divider(
+              height: 1,
+              indent: 16,
+              endIndent: 16,
+              color: Color(0xAA282828),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+/// Data model for [FinancialEntityCategoryView].
+class FinancialEntityCategoryModel {
+  final Color indicatorColor;
+  final double indicatorFraction;
+  final String title;
+  final String subtitle;
+  final double usdAmount;
+  final Widget suffix;
+
+  const FinancialEntityCategoryModel(
+    this.indicatorColor,
+    this.indicatorFraction,
+    this.title,
+    this.subtitle,
+    this.usdAmount,
+    this.suffix,
+  );
+}
+
+FinancialEntityCategoryView buildFinancialEntityFromAccountData(
+  AccountData model,
+  int i,
+) {
+  return FinancialEntityCategoryView(
+    suffix: Icon(Icons.chevron_right, color: Colors.grey),
+    title: model.name,
+    subtitle: '• • • • • • ${model.accountNumber.substring(6)}',
+    indicatorColor: RallyColors.accountColor(i),
+    indicatorFraction: 1.0,
+    amount: model.primaryAmount,
+  );
+}
+
+FinancialEntityCategoryView buildFinancialEntityFromBillData(
+  BillData model,
+  int i,
+) {
+  return FinancialEntityCategoryView(
+    suffix: Icon(Icons.chevron_right, color: Colors.grey),
+    title: model.name,
+    subtitle: model.dueDate,
+    indicatorColor: RallyColors.billColor(i),
+    indicatorFraction: 1.0,
+    amount: model.primaryAmount,
+  );
+}
+
+FinancialEntityCategoryView buildFinancialEntityFromBudgetData(
+  BudgetData item,
+  int i,
+  BuildContext context,
+) {
+  return FinancialEntityCategoryView(
+    suffix: Text(' LEFT',
+        style: Theme.of(context)
+            .textTheme
+            .body1
+            .copyWith(color: RallyColors.gray60, fontSize: 10.0)),
+    title: item.name,
+    subtitle: Formatters.usdWithSign.format(item.amountUsed) +
+        ' / ' +
+        Formatters.usdWithSign.format(item.primaryAmount),
+    indicatorColor: RallyColors.budgetColor(i),
+    indicatorFraction: item.amountUsed / item.primaryAmount,
+    amount: item.primaryAmount - item.amountUsed,
+  );
+}
+
+List<FinancialEntityCategoryView> buildAccountDataListViews(
+    List<AccountData> items) {
+  return List<FinancialEntityCategoryView>.generate(
+      items.length, (i) => buildFinancialEntityFromAccountData(items[i], i));
+}
+
+List<FinancialEntityCategoryView> buildBillDataListViews(List<BillData> items) {
+  return List<FinancialEntityCategoryView>.generate(
+      items.length, (i) => buildFinancialEntityFromBillData(items[i], i));
+}
+
+List<FinancialEntityCategoryView> buildBudgetDataListViews(
+    List<BudgetData> items, BuildContext context) {
+  return [
+    for (var i = 0; i < items.length; i++)
+      buildFinancialEntityFromBudgetData(items[i], i, context)
+  ];
+}
+
+class FinancialEntityCategoryDetailsPage extends StatelessWidget {
+  final List<DetailedEventData> items =
+      DummyDataService.getDetailedEventItems();
+
+  @override
+  Widget build(BuildContext context) {
+    final List<_DetailedEventCard> cards = items
+        .map((i) => _DetailedEventCard(
+              title: i.title,
+              subtitle: Formatters.date.format(i.date),
+              amount: i.amount,
+            ))
+        .toList();
+
+    return Scaffold(
+      appBar: AppBar(
+        elevation: 0.0,
+        centerTitle: true,
+        title: Text(
+          'Checking',
+          style: Theme.of(context).textTheme.body1.copyWith(fontSize: 18.0),
+        ),
+      ),
+      body: Column(children: [
+        SizedBox(
+            height: 200.0,
+            width: double.infinity,
+            child: RallyLineChart(events: items)),
+        Flexible(
+          child: ListView(shrinkWrap: true, children: cards),
+        )
+      ]),
+    );
+  }
+}
+
+class _DetailedEventCard extends StatelessWidget {
+  const _DetailedEventCard({
+    @required this.title,
+    @required this.subtitle,
+    @required this.amount,
+  });
+
+  final String title;
+  final String subtitle;
+  final double amount;
+
+  @override
+  Widget build(BuildContext context) {
+    return FlatButton(
+      onPressed: () {},
+      child: SizedBox(
+        height: 68.0,
+        child: Column(
+          children: [
+            SizedBox(
+              height: 67.0,
+              child: Row(
+                children: [
+                  Column(
+                    mainAxisAlignment: MainAxisAlignment.center,
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      Text(
+                        title,
+                        style: Theme.of(context)
+                            .textTheme
+                            .body1
+                            .copyWith(fontSize: 16.0),
+                      ),
+                      Text(
+                        subtitle,
+                        style: Theme.of(context)
+                            .textTheme
+                            .body1
+                            .copyWith(color: RallyColors.gray60),
+                      )
+                    ],
+                  ),
+                  Spacer(),
+                  Text(
+                    '\$${Formatters.usd.format(amount)}',
+                    style: Theme.of(context)
+                        .textTheme
+                        .body2
+                        .copyWith(fontSize: 20.0, color: RallyColors.gray),
+                  ),
+                ],
+              ),
+            ),
+            Padding(
+              padding: const EdgeInsets.symmetric(horizontal: 16.0),
+              child: SizedBox(
+                height: 1.0,
+                child: Container(
+                  color: Color(0xAA282828),
+                ),
+              ),
+            )
+          ],
+        ),
+      ),
+    );
+  }
+}

material_studies/rally/lib/formatters.dart

@@ -0,0 +1,21 @@
+// Copyright 2019-present the Flutter authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'package:intl/intl.dart';
+
+class Formatters {
+  static final NumberFormat usd = NumberFormat.currency(name: '');
+  static final NumberFormat usdWithSign = NumberFormat.currency(name: '\$');
+  static final DateFormat date = DateFormat('MM-dd-yy');
+}

material_studies/rally/lib/home.dart

@@ -0,0 +1,221 @@
+// Copyright 2019-present the Flutter authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
+import 'package:rally/tabs/accounts.dart';
+import 'package:rally/tabs/bills.dart';
+import 'package:rally/tabs/budgets.dart';
+import 'package:rally/tabs/overview.dart';
+import 'package:rally/tabs/settings.dart';
+
+const int tabCount = 5;
+
+class HomePage extends StatefulWidget {
+  @override
+  _HomePageState createState() => _HomePageState();
+}
+
+class _HomePageState extends State<HomePage>
+    with SingleTickerProviderStateMixin {
+  TabController _tabController;
+
+  _HomePageState() {
+    _tabController = TabController(length: tabCount, vsync: this);
+  }
+
+  @override
+  void initState() {
+    super.initState();
+    print('_HomePageState initState');
+
+    _tabController.addListener(() {
+      if (_tabController.indexIsChanging &&
+          _tabController.previousIndex != _tabController.index) {
+        setState(() {});
+      }
+    });
+  }
+
+  @override
+  dispose() {
+    _tabController.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+
+    return Scaffold(
+      body: SafeArea(
+        child: Column(
+          children: [
+            Theme(
+              // This theme effectively removes the default visual touch
+              // feedback for tapping a tab, which is replaced with a custom
+              // animation.
+              data: theme.copyWith(
+                splashColor: Colors.transparent,
+                highlightColor: Colors.transparent,
+              ),
+              child: TabBar(
+                // Setting isScrollable to true prevents the tabs from being
+                // wrapped in [Expanded] widgets, which allows for more
+                // flexible sizes and size animations among tabs.
+                isScrollable: true,
+                labelPadding: EdgeInsets.zero,
+                tabs: _buildTabs(theme),
+                controller: _tabController,
+                // This removes the tab indicator.
+                indicatorColor: Colors.transparent,
+              ),
+            ),
+            Expanded(
+              child: TabBarView(
+                controller: _tabController,
+                children: _buildTabViews(),
+              ),
+            )
+          ],
+        ),
+      ),
+    );
+  }
+
+  List<Widget> _buildTabs(ThemeData theme) {
+    return <Widget>[
+      _buildTab(theme, Icons.pie_chart, 'OVERVIEW', 0),
+      _buildTab(theme, Icons.attach_money, 'ACCOUNTS', 1),
+      _buildTab(theme, Icons.money_off, 'BILLS', 2),
+      _buildTab(theme, Icons.table_chart, 'BUDGETS', 3),
+      _buildTab(theme, Icons.settings, 'SETTINGS', 4),
+    ];
+  }
+
+  List<Widget> _buildTabViews() {
+    return [
+      OverviewView(),
+      AccountsView(),
+      BillsView(),
+      BudgetsView(),
+      SettingsView(),
+    ];
+  }
+
+  Widget _buildTab(
+    ThemeData theme,
+    IconData iconData,
+    String title,
+    int index,
+  ) {
+    return _RallyTab(
+      theme.textTheme.button,
+      Icon(iconData),
+      title,
+      _tabController.index == index,
+    );
+  }
+}
+
+class _RallyTab extends StatefulWidget {
+  final TextStyle style;
+  final Text titleText;
+  final Icon icon;
+  final bool isExpanded;
+
+  _RallyTab(TextStyle style, Icon icon, String title, bool isExpanded)
+      : this.style = style,
+        this.titleText = Text(title, style: style),
+        this.icon = icon,
+        this.isExpanded = isExpanded;
+
+  _RallyTabState createState() => _RallyTabState();
+}
+
+class _RallyTabState extends State<_RallyTab>
+    with SingleTickerProviderStateMixin {
+  Animation<double> _titleSizeAnimation;
+  Animation<double> _titleFadeAnimation;
+  Animation<double> _iconFadeAnimation;
+  AnimationController _controller;
+
+  @override
+  initState() {
+    super.initState();
+    _controller = AnimationController(
+      duration: Duration(milliseconds: 200),
+      vsync: this,
+    );
+    _titleSizeAnimation = _controller.view;
+    _titleFadeAnimation = _controller.drive(CurveTween(curve: Curves.easeOut));
+    _iconFadeAnimation = _controller.drive(Tween(begin: 0.6, end: 1));
+    if (widget.isExpanded) {
+      _controller.value = 1.0;
+    }
+  }
+
+  @override
+  void didUpdateWidget(_RallyTab oldWidget) {
+    super.didUpdateWidget(oldWidget);
+    if (widget.isExpanded) {
+      _controller.forward();
+    } else {
+      _controller.reverse();
+    }
+  }
+
+  Widget build(BuildContext context) {
+    // Calculate the width of each unexpanded tab by counting the number of
+    // units and dividing it into the screen width. Each unexpanded tab is 1
+    // unit, and there is always 1 expanded tab which is 1 unit + any extra
+    // space determined by the multiplier.
+    final double width = MediaQuery.of(context).size.width;
+    final double expandedTitleWidthMultiplier = 2;
+    final double unitWidth = width / (tabCount + expandedTitleWidthMultiplier);
+
+    return SizedBox(
+      height: 56,
+      child: Row(
+        children: <Widget>[
+          FadeTransition(
+            child: SizedBox(
+              width: unitWidth,
+              child: widget.icon,
+            ),
+            opacity: _iconFadeAnimation,
+          ),
+          FadeTransition(
+            child: SizeTransition(
+              child: SizedBox(
+                width: unitWidth * expandedTitleWidthMultiplier,
+                child: Center(child: widget.titleText),
+              ),
+              axis: Axis.horizontal,
+              axisAlignment: -1,
+              sizeFactor: _titleSizeAnimation,
+            ),
+            opacity: _titleFadeAnimation,
+          ),
+        ],
+      ),
+    );
+  }
+
+  @override
+  dispose() {
+    _controller.dispose();
+    super.dispose();
+  }
+}

material_studies/rally/lib/login.dart

@@ -0,0 +1,68 @@
+// Copyright 2019-present the Flutter authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'package:flutter/material.dart';
+
+class LoginPage extends StatefulWidget {
+  @override
+  _LoginPageState createState() => _LoginPageState();
+}
+
+class _LoginPageState extends State<LoginPage> {
+  final _usernameController = TextEditingController();
+  final _passwordController = TextEditingController();
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      body: SafeArea(
+        child: GestureDetector(
+          onTap: () {
+            Navigator.pop(context);
+          },
+          child: ListView(
+            padding: EdgeInsets.symmetric(horizontal: 24),
+            children: [
+              Padding(
+                padding: const EdgeInsets.symmetric(vertical: 64),
+                child: SizedBox(
+                  height: 160,
+                  child: Image.asset('assets/logo.png'),
+                ),
+              ),
+              TextField(
+                controller: _usernameController,
+                decoration: InputDecoration(
+                  labelText: 'Username',
+                ),
+              ),
+              SizedBox(height: 12),
+              TextField(
+                controller: _passwordController,
+                decoration: InputDecoration(
+                  labelText: 'Password',
+                ),
+                obscureText: true,
+              ),
+              SizedBox(
+                height: 120,
+                child: Image.asset('assets/thumb.png'),
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}

material_studies/rally/lib/main.dart

@@ -0,0 +1,18 @@
+// Copyright 2019-present the Flutter authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'package:flutter/material.dart';
+import 'package:rally/app.dart';
+
+void main() => runApp(RallyApp());

material_studies/rally/lib/tabs/accounts.dart

@@ -0,0 +1,37 @@
+// Copyright 2019-present the Flutter authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
+
+import 'package:rally/data.dart';
+import 'package:rally/finance.dart';
+import 'package:rally/charts/pie_chart.dart';
+
+/// A page that shows a summary of accounts.
+class AccountsView extends StatelessWidget {
+  final List<AccountData> items = DummyDataService.getAccountDataList();
+
+  @override
+  Widget build(BuildContext context) {
+    double balanceTotal = sumAccountDataPrimaryAmount(items);
+    return FinancialEntityView(
+      heroLabel: 'Total',
+      heroAmount: balanceTotal,
+      segments: buildSegmentsFromAccountItems(items),
+      wholeAmount: balanceTotal,
+      financialEntityCards: buildAccountDataListViews(items),
+    );
+  }
+}

material_studies/rally/lib/tabs/bills.dart

@@ -0,0 +1,43 @@
+// Copyright 2019-present the Flutter authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
+
+import 'package:rally/data.dart';
+import 'package:rally/finance.dart';
+import 'package:rally/charts/pie_chart.dart';
+
+/// A page that shows a summary of bills.
+class BillsView extends StatefulWidget {
+  @override
+  _BillsViewState createState() => _BillsViewState();
+}
+
+class _BillsViewState extends State<BillsView>
+    with SingleTickerProviderStateMixin {
+  final List<BillData> items = DummyDataService.getBillDataList();
+
+  @override
+  Widget build(BuildContext context) {
+    double dueTotal = sumBillDataPrimaryAmount(items);
+    return FinancialEntityView(
+      heroLabel: 'Due',
+      heroAmount: dueTotal,
+      segments: buildSegmentsFromBillItems(items),
+      wholeAmount: dueTotal,
+      financialEntityCards: buildBillDataListViews(items),
+    );
+  }
+}

material_studies/rally/lib/tabs/budgets.dart

@@ -0,0 +1,43 @@
+// Copyright 2019-present the Flutter authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
+
+import 'package:rally/charts/pie_chart.dart';
+import 'package:rally/data.dart';
+import 'package:rally/finance.dart';
+
+class BudgetsView extends StatefulWidget {
+  @override
+  _BudgetsViewState createState() => _BudgetsViewState();
+}
+
+class _BudgetsViewState extends State<BudgetsView>
+    with SingleTickerProviderStateMixin {
+  final List<BudgetData> items = DummyDataService.getBudgetDataList();
+
+  @override
+  Widget build(BuildContext context) {
+    double capTotal = sumBudgetDataPrimaryAmount(items);
+    double usedTotal = sumBudgetDataAmountUsed(items);
+    return FinancialEntityView(
+      heroLabel: 'Left',
+      heroAmount: capTotal - usedTotal,
+      segments: buildSegmentsFromBudgetItems(items),
+      wholeAmount: capTotal,
+      financialEntityCards: buildBudgetDataListViews(items, context),
+    );
+  }
+}

material_studies/rally/lib/tabs/overview.dart

@@ -0,0 +1,151 @@
+// Copyright 2019-present the Flutter authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'dart:math';
+
+import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
+
+import 'package:rally/colors.dart';
+import 'package:rally/data.dart';
+import 'package:rally/finance.dart';
+import 'package:rally/formatters.dart';
+
+/// A page that shows a status overview.
+class OverviewView extends StatefulWidget {
+  @override
+  _OverviewViewState createState() => _OverviewViewState();
+}
+
+class _OverviewViewState extends State<OverviewView> {
+  @override
+  Widget build(BuildContext context) {
+    final accountDataList = DummyDataService.getAccountDataList();
+    final billDataList = DummyDataService.getBillDataList();
+    final budgetDataList = DummyDataService.getBudgetDataList();
+
+    return Padding(
+      padding: EdgeInsets.symmetric(horizontal: 16, vertical: 8),
+      child: ListView(children: [
+        _AlertsView(),
+        SizedBox(height: 16),
+        _FinancialView(
+          title: 'Accounts',
+          total: sumAccountDataPrimaryAmount(accountDataList),
+          financialItemViews: buildAccountDataListViews(accountDataList),
+        ),
+        SizedBox(height: 16),
+        _FinancialView(
+          title: 'Bills',
+          total: sumBillDataPrimaryAmount(billDataList),
+          financialItemViews: buildBillDataListViews(billDataList),
+        ),
+        SizedBox(height: 16),
+        _FinancialView(
+          title: 'Budgets',
+          total: sumBudgetDataPrimaryAmount(budgetDataList),
+          financialItemViews: buildBudgetDataListViews(budgetDataList, context),
+        ),
+        SizedBox(height: 16),
+      ]),
+    );
+  }
+}
+
+class _AlertsView extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      padding: EdgeInsets.only(left: 16, top: 4, bottom: 4),
+      color: RallyColors.cardBackground,
+      child: Column(
+        children: [
+          Row(
+            mainAxisAlignment: MainAxisAlignment.spaceBetween,
+            children: [
+              Text('Alerts'),
+              FlatButton(
+                onPressed: () {},
+                child: Text('SEE ALL'),
+                textColor: Colors.white,
+              ),
+            ],
+          ),
+          Container(color: RallyColors.primaryBackground, height: 1),
+          Row(
+            mainAxisAlignment: MainAxisAlignment.spaceBetween,
+            children: [
+              Expanded(
+                child: Text(
+                    'Heads up, you’ve used up 90% of your Shopping budget for '
+                    'this month.'),
+              ),
+              SizedBox(
+                width: 100,
+                child: Align(
+                  alignment: Alignment.topRight,
+                  child: IconButton(
+                    onPressed: () {},
+                    icon: Icon(Icons.sort, color: RallyColors.white60),
+                  ),
+                ),
+              ),
+            ],
+          )
+        ],
+      ),
+    );
+  }
+}
+
+class _FinancialView extends StatelessWidget {
+  _FinancialView({this.title, this.total, this.financialItemViews});
+
+  final String title;
+  final double total;
+  final List<FinancialEntityCategoryView> financialItemViews;
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+    return Container(
+      color: RallyColors.cardBackground,
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.stretch,
+        children: [
+          Padding(
+            padding: EdgeInsets.all(16),
+            child: Text(title),
+          ),
+          Padding(
+            padding: EdgeInsets.only(left: 16, right: 16),
+            child: Text(
+              Formatters.usdWithSign.format(total),
+              style: theme.textTheme.body2.copyWith(
+                fontSize: 44.0,
+                fontWeight: FontWeight.w600,
+              ),
+            ),
+          ),
+          ...financialItemViews.sublist(0, min(financialItemViews.length, 3)),
+          FlatButton(
+            child: Text('SEE ALL'),
+            textColor: Colors.white,
+            onPressed: () {},
+          ),
+        ],
+      ),
+    );
+  }
+}

material_studies/rally/lib/tabs/settings.dart

@@ -0,0 +1,54 @@
+// Copyright 2019-present the Flutter authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
+
+import 'package:rally/data.dart';
+
+class SettingsView extends StatefulWidget {
+  @override
+  _SettingsViewState createState() => _SettingsViewState();
+}
+
+class _SettingsViewState extends State<SettingsView> {
+  List<Widget> items = DummyDataService.getSettingsTitles()
+      .map((title) => _SettingsItem(title))
+      .toList();
+
+  @override
+  Widget build(BuildContext context) {
+    return ListView(children: items);
+  }
+}
+
+class _SettingsItem extends StatelessWidget {
+  _SettingsItem(this.title);
+
+  final String title;
+
+  @override
+  Widget build(BuildContext context) {
+    return FlatButton(
+      textColor: Colors.white,
+      child: SizedBox(
+        height: 60,
+        child: Row(children: <Widget>[
+          Text(title),
+        ]),
+      ),
+      onPressed: () {},
+    );
+  }
+}

material_studies/rally/pubspec.yaml

@@ -0,0 +1,39 @@
+name: rally
+description: Rally
+version: 1.0.0+1
+
+environment:
+  sdk: ">=2.2.2 <3.0.0"
+
+dependencies:
+  flutter:
+    sdk: flutter
+  cupertino_icons: ^0.1.2
+  intl: ^0.15.7
+
+dev_dependencies:
+  flutter_test:
+    sdk: flutter
+
+flutter:
+  uses-material-design: true
+  assets:
+    - assets/logo.png
+    - assets/thumb.png
+  fonts:
+    - family: Roboto Condensed
+      fonts:
+        - asset: fonts/RobotoCondensed-Light.ttf
+          weight: 400
+        - asset: fonts/RobotoCondensed-Regular.ttf
+          weight: 500
+        - asset: fonts/RobotoCondensed-Bold.ttf
+          weight: 700
+    - family: Eczar
+      fonts:
+        - asset: fonts/Eczar-Regular.ttf
+          weight: 400
+        - asset: fonts/Eczar-SemiBold.ttf
+          weight: 600
+        - asset: fonts/Eczar-Bold.ttf
+          weight: 700

material_studies/rally/test/widget_test.dart

@@ -0,0 +1,18 @@
+// This is a basic Flutter widget test.
+//
+// To perform an interaction with a widget in your test, use the WidgetTester
+// utility that Flutter provides. For example, you can send tap and scroll
+// gestures. You can also use WidgetTester to find child widgets in the widget
+// tree, read text, and verify that the values of widget properties are correct.
+
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+import 'package:rally/app.dart';
+
+void main() {
+  testWidgets('Smoke test', (tester) async {
+    await tester.pumpWidget(RallyApp());
+    expect(find.byType(MaterialApp), findsOneWidget);
+  });
+}