Nevron Open Vision Documentation
Chart / Interactivity / Hit Testing
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    Hit Testing
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    In NOV Chart for .NET hit testing is achieved by subscribing to one of the keyboard or mouse events exposed by the NChartElement class. This class is similar to the Input element class in NOV UI and for more information you can visit the Input Elements topic. The following code snippet shows how to implement an interactive pie chart:

    C#
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    NChartView chartView = new NChartView();

    // create a dock panel with label and chart
    NDockPanel dockPanel = new NDockPanel();
    chartView.Surface.Content = dockPanel;

    // crete a docked label
    NLabel label = new NLabel();
    label.Text =
    "Interactive Pie Chart";
    label.Margins =
    new NMargins(10);
    NDockLayout.SetDockArea(label, ENDockArea.Top);
    dockPanel.AddChild(label);

    // create a new cartesian chart
    NPieChart pieChart = new NPieChart();
    NDockLayout.SetDockArea(pieChart, ENDockArea.Center);
    dockPanel.AddChild(pieChart);

    NPieSeries pieSeries = new NPieSeries();
    pieChart.Series.Add(pieSeries);
    pieSeries.DataPoints.Add(CreateDataPoint(10));
    pieSeries.DataPoints.Add(CreateDataPoint(20));
    pieSeries.DataPoints.Add(CreateDataPoint(30));

    ...

    private NPieDataPoint CreateDataPoint(double value)

    {

    NPieDataPoint pieDataPoint = new NPieDataPoint(value);
    pieDataPoint.MouseDown +=
    new Function<NMouseButtonEventArgs>(pieDataPoint_MouseDown);
    return pieDataPoint;

    }

    void pieDataPoint_MouseDown(NMouseButtonEventArgs arg)

    {

    NPieDataPoint pieDataPoint = (NPieDataPoint)arg.TargetNode;
    pieDataPoint.Fill =
    new NColorFill(NColor.Red);

    }

    In this example when the user clicks on a pie slice it will turn red.
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