samples/web/charts/lib/i18n/rtl_line_chart.dart

// 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.

/// RTL 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/material.dart';

class RTLLineChart extends StatelessWidget {
  final List<charts.Series> seriesList;
  final bool animate;

  const RTLLineChart(this.seriesList, {this.animate, Key key})
      : super(key: key);

  /// Creates a [LineChart] with sample data and no transition.
  factory RTLLineChart.withSampleData() {
    return RTLLineChart(
      _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 RTLLineChart.withRandomData() {
    return RTLLineChart(_createRandomData());
  }

  /// Create random data.
  static List<charts.Series<LinearSales, num>> _createRandomData() {
    final random = Random();

    final data = [
      LinearSales(0, random.nextInt(100)),
      LinearSales(1, random.nextInt(100)),
      LinearSales(2, random.nextInt(100)),
      LinearSales(3, random.nextInt(100)),
    ];

    return [
      charts.Series<LinearSales, int>(
        id: 'Sales',
        domainFn: (LinearSales sales, _) => sales.year,
        measureFn: (LinearSales sales, _) => sales.sales,
        data: data,
      )
    ];
  }
  // EXCLUDE_FROM_GALLERY_DOCS_END

  @override
  Widget build(BuildContext context) {
    // Charts will determine if RTL is enabled by checking the directionality by
    // requesting Directionality.of(context). This returns the text direction
    // from the closest instance of that encloses the context passed to build
    // the chart. A [TextDirection.rtl] will be treated as a RTL chart. This
    // means that the directionality widget does not have to directly wrap each
    // chart. It is show here as an example only.
    //
    // By default, when a chart detects RTL:
    // Measure axis positions are flipped. Primary measure axis is on the right
    // and the secondary measure axis is on the left (when used).
    // Domain axis' first domain starts on the right and grows left.
    return Directionality(
        textDirection: TextDirection.rtl,
        child: charts.LineChart(
          seriesList,
          animate: animate,
        ));
  }

  /// Create one series with sample hard coded data.
  static List<charts.Series<LinearSales, int>> _createSampleData() {
    final data = [
      LinearSales(0, 5),
      LinearSales(1, 25),
      LinearSales(2, 100),
      LinearSales(3, 75),
    ];

    return [
      charts.Series<LinearSales, int>(
        id: 'Sales',
        domainFn: (LinearSales sales, _) => sales.year,
        measureFn: (LinearSales sales, _) => sales.sales,
        data: data,
      )
    ];
  }
}

/// Sample linear data type.
class LinearSales {
  final int year;
  final int sales;

  LinearSales(this.year, this.sales);
}