RadChart Legend Will Not Show New Items

[Marie C]

I have a RadChart (2011.2.920.1040) that is filled in code behind using WCF results. The user is allowed to pick the data they want to chart.  This works the first time but if they make a second choice, the legend is empty. 

Before I cleared the dataseries, the chart and legend kept the old data along with the new.  Now that I have cleared the dataseries, if the user makes a second selection, the legend is empty. 

I manually added a legend item to the ChartLegend and the associated legend but the legend is still empty. 

// Global Variables

 

 

RadChart chartName =

new RadChart();

 

 

 

ChartLegend chartLegend =

 

 

new ChartLegend();

 

 

 

// SET LEGEND TO CHARTAREA

 

chartName.DefaultView.ChartArea.LegendName =

 

"chartLegend";

 

 

 

// Clear the previously plotted data if this is not the first time through
chartName.DefaultView.ChartArea.Legend.Items.Clear();
chartName.DefaultView.ChartArea.DataSeries.Clear();

 

// CREATE A SERIES FOR EACH SENSOR RETURNED.

 

 

foreach (var sensorItem in sensorReturned)

 

{

 

 

DataSeries lineSeries = new DataSeries();

 

lineSeries.LegendLabel = sensorItem.ToString();

lineSeries.Definition =

 

new LineSeriesDefinition();

 

 

 

var sensorPlotItems = (from p in e.Result 
                        where p.SensorName == sensorItem
                        select p).ToList();

 

 

 

foreach (var item in sensorPlotItems)

 

{

lineSeries.Add(

 

new DataPoint() { XCategory = item.TimeStamp.ToString(), YValue = item.SelectedFieldValue, LegendLabel = sensorItem.ToString() });

 

}

chartName.DefaultView.ChartArea.DataSeries.Add(lineSeries);

 

 

ChartLegendItem legendItem = new ChartLegendItem();

 

legendItem.Label = sensorItem.ToString();

chartLegend.Items.Add(legendItem);

chartName.DefaultView.ChartLegend.Items.Add(legendItem);

 

 

// TEST TO SEE IF THE NEWLY ADDED LEGEND ITEM IS INSIDE THE LEGEND

 

 

 

bool associatedLegendFilled = chartLegend.HasItems; // true but nothing shows

 

 

 

bool filled = chartName.DefaultView.ChartLegend.HasItems; // false

 

}

Any ideas?

[Marie C]

Problem solved.  I removed the line setting the chartName.DefaultView.ChartLegend.ItemsSource = null.  All works fine now. 

 

 

// CLEAR ALL DATA FROM SELECTEDSENSORS AND CHART

 

selectedSensors.Clear();

 

 

chartName.ItemsSource =

null;

 

chartName.DefaultView.ChartArea.ItemsSource =

 

 

 

null;

 

 

 

//chartName.DefaultView.ChartLegend.ItemsSource = null;

 

chartName.DefaultView.ChartArea.AxisX.ChartArea.ItemsSource =

 

//chartName.DefaultView.ChartLegend.ItemsSource = null;

 

 

 

 

 

 

null;

 

chartName.DefaultView.ChartArea.Legend.Items.Clear();

 

 

chartName.DefaultView.ChartArea.DataSeries.Clear();