WPF Toolkit Chart Unordered LineSeries

问题:

The default LineSeries implementation orders data points by independed value. This gives me strange results for data like this:

Is it possible to plot a line series where lines are drawn between the points in the original order?

回答1:

I currently solved this by inheriting from LineSeries:

class UnorderedLineSeries : LineSeries
{
    protected override void UpdateShape()
    {
        double maximum = ActualDependentRangeAxis.GetPlotAreaCoordinate(
            ActualDependentRangeAxis.Range.Maximum).Value;

        Func<DataPoint, Point> PointCreator = dataPoint =>
            new Point(
                ActualIndependentAxis.GetPlotAreaCoordinate(
                dataPoint.ActualIndependentValue).Value,
                maximum - ActualDependentRangeAxis.GetPlotAreaCoordinate(
                dataPoint.ActualDependentValue).Value);

        IEnumerable<Point> points = Enumerable.Empty<Point>();
        if (CanGraph(maximum))
        {
            // Original implementation performs ordering here
            points = ActiveDataPoints.Select(PointCreator);
        }
        UpdateShapeFromPoints(points);
    }

    bool CanGraph(double value)
    {
        return !double.IsNaN(value) &&
            !double.IsNegativeInfinity(value) &&
            !double.IsPositiveInfinity(value) &&
            !double.IsInfinity(value);
    }
}

Result:

回答2:

It's worth pointing out that, to use @hansmaad's suggestion above, you will need to create a new namespace and point your XAML to this, rather than the assembly. i.e.

XAML:

xmlns:chart="clr-namespace:MyApplication.UserControls.Charting"

C#:

using System.Windows.Controls.DataVisualization.Charting;
using System.Windows;

namespace MyApplication.UserControls.Charting {

    class Chart : System.Windows.Controls.DataVisualization.Charting.Chart {}

    class UnorderedLineSeries : LineSeries {
     ....
    }      
}