Setting colours of 3d pie chart items in code-behind

[Adam]

I have just started working with Telerik controls having moved from Infragistics controls.

I have created a 3D pie chart in code-behind whose data is gathered from a database.

The legend items for the chart are also gathered from the database (both the title of each item and its colour is stored in the database as these colours are customisable by the user for each category).

I have managed to set the legend item colours correctly but now I need to set the colours of each 'slice' of the pie chart to match the legend.

I have followed the example on setting custom item styles at http://www.telerik.com/help/wpf/radchart-styling-and-appearance-custom-item-style.html but when I set a breakpoint on the BuildCustomItemStyles method it is only ever trying to style the legend items.

Here is my cod behind (including the BuildCustomItemStyles code).

/// <summary>
/// Interaction logic for AbsenceByReasonChart.xaml
/// </summary>
public partial class AbsenceByReasonChart : UserControl, IWpfChart
{
    private List<OptionPropertiesData> optionPropertiesSet;
    /// <summary>
    ///     Default constructor.
    /// </summary>
    public AbsenceByReasonChart()
    {
        InitializeComponent();
        radChart1.
        Loaded += new RoutedEventHandler(AbsenceByReasonChart_Loaded);
    }
    private void AbsenceByReasonChart_Loaded(object sender, RoutedEventArgs e)
    {
        WpfZoomUtils.ZoomChartArea(radChart1.DefaultView.ChartArea, Constants.WpfChartZoomFactor);
    }

    private Style BuildCustomItemStyle(Control item, Style style, DataPoint point, DataSeries dataSeries)
    {
        if ((item as BaseChartItem3D<Pie3D>) == null) return style;
        Style newStyle = new Style();
        newStyle.BasedOn = style;
        newStyle.TargetType = typeof(Shape);
        // this code gets the brush colour
        Brush brush = new SolidColorBrush(getOptionColour(...));

        newStyle.Setters.Add(new Setter(Shape.FillProperty, brush));

        return newStyle;
    }
    public void SetChartTitle(DateTime startDate, DateTime endDate)
    {
        if (startDate == DateTime.MinValue || startDate == null) return;
        radChart1.DefaultView.ChartTitle.Content = string.Format("Absence by Reason {0} to {1}", startDate.ToShortDateString(), endDate.ToShortDateString());
        radChart1.DefaultView.ChartTitle.HorizontalAlignment = HorizontalAlignment.Center;
    }
    public void PopulateChart(DataTable data, DateTime startDate, DateTime endDate, List<OptionPropertiesData> optionPropertiesList)
    {
        if (data == null || data.Rows.Count == 0 || optionPropertiesList == null || optionPropertiesList.Count == 0) return;
        optionPropertiesSet = optionPropertiesList;
        if (radChart1.DefaultView.ChartArea.DataSeries != null && radChart1.DefaultView.ChartArea.DataSeries.Count > 0)
        {
            // remove existing data series
            radChart1.DefaultView.ChartArea.DataSeries.Clear();
        }
        // define series data type
        DataSeries series = new DataSeries()
        {
            Definition = new Pie3DSeriesDefinition(),
            LegendLabel = "Attendance Type"
        };
        // turn on item tooltips and set the item format of the tooltip for each series item
        ISeries3DDefinition chartDefintion = series.Definition as Pie3DSeriesDefinition;
        if (chartDefintion != null)
        {
            chartDefintion.ShowItemToolTips = true;
            chartDefintion.ItemToolTipFormat = "#LEGENDLABEL: #Y Employees";
            chartDefintion.ItemLabelFormat = "#%{p0}";
        }
        // for the absence by reason chart, the legend colours must match the colours defined for each atendance type
        // in the attendance maintenance section

        // first, turn OFF the automatic generation of the legend for the chart
        radChart1.DefaultView.ChartLegend.UseAutoGeneratedItems = false;
        // whilst the chart is being populated, set the legend item appropriately
        foreach (DataRow r in data.Rows)
        {
            if (r == null || r.ItemArray == null || r.ItemArray.Length == 0) continue;
            // the item array of each data row has the following information:
            // first item is the absence reason
            // second item is the number of employees off due to this reason
            // third item is the id of the data option for the absence reason
            if (r.ItemArray[1] is int && r.ItemArray[0] is string && r.ItemArray[2] is long)
            {
                // ignore categories that have no value or rows where the absence reason data option id cannot be found
                if (Convert.ToInt32(r.ItemArray[1]) <= 0 || Convert.ToInt64(r.ItemArray[2]) <= 0) continue;
                // set the data for this category
                series.Add(new DataPoint
                {
                    XValue = Convert.ToInt64(r.ItemArray[2]),
                    YValue = Convert.ToInt32(r.ItemArray[1]),
                });
                // now define its legend item
                ChartLegendItem legendItem = new ChartLegendItem()
                {
                    Background = new SolidColorBrush(getOptionColour(Convert.ToInt64(r.ItemArray[2]), optionPropertiesList)),
                    Label = Convert.ToString(r.ItemArray[0])
                };
                radChart1.DefaultView.ChartLegend.Items.Add(legendItem);
            }
        }
        SetChartTitle(startDate, endDate);
        // finally, assign the chart the defined data series
        radChart1.DefaultView.ChartArea.DataSeries.Add(series);
    }
    private System.Windows.Media.Color getOptionColour(long optionID, List<OptionPropertiesData> optionPropertiesList)
    {
        // find the option properties object for the option with the passed in option id
        // and return its associated colour
        OptionPropertiesData optionProperty = optionPropertiesList.Find(delegate(OptionPropertiesData opData) { return opData.getDataOptionID() == optionID; });
        if (optionProperty != null)
        {
            System.Drawing.Color winFormColour = System.Drawing.Color.FromArgb(optionProperty.getPlannerColour());
            if (winFormColour != null)
            {
                return new System.Windows.Media.Color()
                {
                    A = winFormColour.A,
                    R = winFormColour.R,
                    G = winFormColour.G,
                    B = winFormColour.G
                };
            }
        }
        return new Color();
    }
    public RadChart GetChartInstance()
    {
        return radChart1;
    }

[Vladimir Milev]

Hi Adam,

The easiest way to style both is using a custom palette: http://demos.telerik.com/silverlight/#Chart/CustomPalette

Best wishes,
Vladimir Milev
the Telerik team