DataSource Class

Allows you to bind a chart to a data source.

Assembly: DevExpress.WinUI.Charts.v22.1.dll

Declaration

C#
VB.NET

public class DataSource :
    DataSourceBase,
    IDisposable

Public Class DataSource
    Inherits DataSourceBase
    Implements IDisposable

Remarks

Perform the following steps to bind a chart to a data source:

Initialize the Series.Data, PieSeries.Data, or FunnelSeries.Data property with a DataSource object.
Define the DataSource.PointSource property to specify the name of a point collection.
Use the DataSource.ArgumentDataMember and DataSource.ValueDataMember properties to specify data members that store arguments and values.

For more information on how to populate a chart with data, refer to the following topic: Load Chart Data.

Example

The following example demonstrates how to bind a chart to data from a ViewModel.

Chart bound to data

To do this, it is necessary to assign the DataSource object to the Series.Data property and specify the data source for the adapter in its DataSource.PointSource property.

XAML

<Window
    x:Class="DataSourceExample.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:DataSourceExample"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:Charts="using:DevExpress.WinUI.Charts"
    mc:Ignorable="d">

    <Grid>
        <Charts:CartesianChart x:Name="chart">
            <Charts:Series>
                <Charts:Series.View>
                    <Charts:LineSeriesView/>
                </Charts:Series.View>
                <Charts:Series.Data>
                    <Charts:DataSource PointSource="{Binding ItemsSource}" 
                                       ArgumentDataMember="PointArgument" 
                                       ValueDataMember="PointValue"/>
                </Charts:Series.Data>
            </Charts:Series>
            <Charts:CartesianChart.AxisX>
                <Charts:AxisX DateTimeGridAlignment="Year" 
                              DateTimeMeasureUnit="Hour" 
                              LabelPattern="{}{V:yyyy}"/>
            </Charts:CartesianChart.AxisX>
        </Charts:CartesianChart>
    </Grid>
</Window>

using Microsoft.UI.Xaml;
using System;
using System.Collections;
using System.Collections.Generic;

namespace DataSourceExample {

    public sealed partial class MainWindow : Window {
        public MainWindow() {
            this.InitializeComponent();
            chart.DataContext = new ViewModel() {
                Start = 10000,
                Count = 50000,
                Step = TimeSpan.FromHours(3),
            };
        }
    }
    public class DateTimeDataPoint {
        public DateTime PointArgument { get; set; }
        public double PointValue { get; set; }
    }

    public class ViewModel {
        DateTime start = new DateTime(2000, 1, 1);
        IEnumerable itemsSource;
        readonly Random random = new Random();


        public TimeSpan Step { get; set; }
        public int Count { get; set; }
        public double Start { get; set; }
        public IEnumerable ItemsSource {
            get { return itemsSource ??= CreateItemsSource(Count); }
        }

        protected IEnumerable CreateItemsSource(int count) {
            var points = new List<DateTimeDataPoint>();

            double value = GenerateStartValue(random);
            points.Add(new DateTimeDataPoint() { PointArgument = start, PointValue = value });
            for (int i = 1; i < count; i++) {
                value += GenerateAddition(random);
                start += Step;
                points.Add(new DateTimeDataPoint() { PointArgument = start, PointValue = value });
            }
            return points;
        }

        protected double GenerateStartValue(Random random) {
            return Start + random.NextDouble() * 100;
        }

        protected double GenerateAddition(Random random) {
            double factor = random.NextDouble();
            if (factor == 1)
                factor = 50;
            else if (factor == 0)
                factor = -50;
            return (factor - 0.5) * 50;
        }
    }
}