Adding Rally App to Flutter Samples (#135)

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),
+    );
+  }
+}