Add flutter_web samples (#75)

web/charts/example/lib/line_chart/dash_pattern.dart

@@ -0,0 +1,162 @@
+// Copyright 2018 the Charts project authors. Please see the AUTHORS file
+// for details.
+//
+// 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.
+
+/// Dash pattern line chart example
+// EXCLUDE_FROM_GALLERY_DOCS_START
+import 'dart:math';
+// EXCLUDE_FROM_GALLERY_DOCS_END
+import 'package:charts_flutter/flutter.dart' as charts;
+import 'package:flutter_web/material.dart';
+
+/// Example of a line chart rendered with dash patterns.
+class DashPatternLineChart extends StatelessWidget {
+  final List<charts.Series> seriesList;
+  final bool animate;
+
+  DashPatternLineChart(this.seriesList, {this.animate});
+
+  /// Creates a [LineChart] with sample data and no transition.
+  factory DashPatternLineChart.withSampleData() {
+    return new DashPatternLineChart(
+      _createSampleData(),
+      // Disable animations for image tests.
+      animate: false,
+    );
+  }
+
+  // EXCLUDE_FROM_GALLERY_DOCS_START
+  // This section is excluded from being copied to the gallery.
+  // It is used for creating random series data to demonstrate animation in
+  // the example app only.
+  factory DashPatternLineChart.withRandomData() {
+    return new DashPatternLineChart(_createRandomData());
+  }
+
+  /// Create random data.
+  static List<charts.Series<LinearSales, num>> _createRandomData() {
+    final random = new Random();
+
+    final myFakeDesktopData = [
+      new LinearSales(0, random.nextInt(100)),
+      new LinearSales(1, random.nextInt(100)),
+      new LinearSales(2, random.nextInt(100)),
+      new LinearSales(3, random.nextInt(100)),
+    ];
+
+    var myFakeTabletData = [
+      new LinearSales(0, random.nextInt(100)),
+      new LinearSales(1, random.nextInt(100)),
+      new LinearSales(2, random.nextInt(100)),
+      new LinearSales(3, random.nextInt(100)),
+    ];
+
+    var myFakeMobileData = [
+      new LinearSales(0, random.nextInt(100)),
+      new LinearSales(1, random.nextInt(100)),
+      new LinearSales(2, random.nextInt(100)),
+      new LinearSales(3, random.nextInt(100)),
+    ];
+
+    return [
+      new charts.Series<LinearSales, int>(
+        id: 'Desktop',
+        colorFn: (_, __) => charts.MaterialPalette.blue.shadeDefault,
+        domainFn: (LinearSales sales, _) => sales.year,
+        measureFn: (LinearSales sales, _) => sales.sales,
+        data: myFakeDesktopData,
+      ),
+      new charts.Series<LinearSales, int>(
+        id: 'Tablet',
+        colorFn: (_, __) => charts.MaterialPalette.red.shadeDefault,
+        dashPatternFn: (_, __) => [2, 2],
+        domainFn: (LinearSales sales, _) => sales.year,
+        measureFn: (LinearSales sales, _) => sales.sales,
+        data: myFakeTabletData,
+      ),
+      new charts.Series<LinearSales, int>(
+        id: 'Mobile',
+        colorFn: (_, __) => charts.MaterialPalette.green.shadeDefault,
+        dashPatternFn: (_, __) => [8, 3, 2, 3],
+        domainFn: (LinearSales sales, _) => sales.year,
+        measureFn: (LinearSales sales, _) => sales.sales,
+        data: myFakeMobileData,
+      )
+    ];
+  }
+  // EXCLUDE_FROM_GALLERY_DOCS_END
+
+  @override
+  Widget build(BuildContext context) {
+    return new charts.LineChart(seriesList, animate: animate);
+  }
+
+  /// Create three series with sample hard coded data.
+  static List<charts.Series<LinearSales, int>> _createSampleData() {
+    final myFakeDesktopData = [
+      new LinearSales(0, 5),
+      new LinearSales(1, 25),
+      new LinearSales(2, 100),
+      new LinearSales(3, 75),
+    ];
+
+    var myFakeTabletData = [
+      new LinearSales(0, 10),
+      new LinearSales(1, 50),
+      new LinearSales(2, 200),
+      new LinearSales(3, 150),
+    ];
+
+    var myFakeMobileData = [
+      new LinearSales(0, 15),
+      new LinearSales(1, 75),
+      new LinearSales(2, 300),
+      new LinearSales(3, 225),
+    ];
+
+    return [
+      new charts.Series<LinearSales, int>(
+        id: 'Desktop',
+        colorFn: (_, __) => charts.MaterialPalette.blue.shadeDefault,
+        domainFn: (LinearSales sales, _) => sales.year,
+        measureFn: (LinearSales sales, _) => sales.sales,
+        data: myFakeDesktopData,
+      ),
+      new charts.Series<LinearSales, int>(
+        id: 'Tablet',
+        colorFn: (_, __) => charts.MaterialPalette.red.shadeDefault,
+        dashPatternFn: (_, __) => [2, 2],
+        domainFn: (LinearSales sales, _) => sales.year,
+        measureFn: (LinearSales sales, _) => sales.sales,
+        data: myFakeTabletData,
+      ),
+      new charts.Series<LinearSales, int>(
+        id: 'Mobile',
+        colorFn: (_, __) => charts.MaterialPalette.green.shadeDefault,
+        dashPatternFn: (_, __) => [8, 3, 2, 3],
+        domainFn: (LinearSales sales, _) => sales.year,
+        measureFn: (LinearSales sales, _) => sales.sales,
+        data: myFakeMobileData,
+      )
+    ];
+  }
+}
+
+/// Sample linear data type.
+class LinearSales {
+  final int year;
+  final int sales;
+
+  LinearSales(this.year, this.sales);
+}