<telerik:ChartArea x:Name="chart"
                 Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="2"
              ItemClick="chartDianZong_ItemClick" />
//----------------
DataSeries barSeries = GetData();
            barSeries.Definition.InteractivitySettings.HoverScope = InteractivityScope.Item;
            barSeries.Definition.InteractivitySettings.SelectionScope = InteractivityScope.Item;
            barSeries.Definition.InteractivitySettings.SelectionMode = ChartSelectionMode.Single;

            barSeries.Definition.ShowItemToolTips = true;

            chart.DataSeries.Add(barSeries);

            chart.AxisY.Title = "";
            chart.AxisY.AxisStyles.TitleStyle = Resources["CustomAxisTitleStyle"] as Style;
            chart.AxisY.ExtendDirection = AxisExtendDirection.None;
            chart.AxisY.AutoRange = false;
            chart.AxisY.AddRange(0, 35000, 5000);

----
every time click,chart.SelectItems will add 1 .
ChartSelectionMode.Single is not use,why?

Hello ji,

We tested the described scenario and it behaves as expected -- there is always at most one selected item in the bar series (that is what SelectionMode.Single means).

Find attached a sample application for your reference.


Kind regards,
Freddie
the Telerik team

Thank you.

After I change my code by sample application,SelectedItems.Count is always 1.

but these code will not behaves as expected ,i think these is a bug.

<Grid x:Name="LayoutRoot" Background="White">
        <Grid.RowDefinitions>
      
            <RowDefinition Height="*"/>
   
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>

        <telerik:RadChart Name="RadChart1" Grid.Row="0" />

        <telerik:ChartArea Name="chart2" Grid.Row="1"   />
    </Grid>

//**********************

namespace SilverlightApplication1
{
    public partial class MainPage : UserControl
    {
        public MainPage()
        {
            InitializeComponent();

            List<ChartData> data = new List<ChartData>();
            data.Add(new ChartData() { Y = 10 });
            data.Add(new ChartData() { Y = 20 });
            data.Add(new ChartData() { Y = 30 });
            data.Add(new ChartData() { Y = 40 });

            SeriesMapping sm = new SeriesMapping();
            sm.SeriesDefinition = new BarSeriesDefinition();
            sm.SeriesDefinition.InteractivitySettings.HoverScope = InteractivityScope.Item;
            sm.SeriesDefinition.InteractivitySettings.SelectionScope = InteractivityScope.Item;
            sm.SeriesDefinition.InteractivitySettings.SelectionMode = ChartSelectionMode.Single;
            sm.ItemMappings.Add(new ItemMapping("Y", DataPointMember.YValue));

            RadChart1.DefaultView.ChartArea.AxisY.ExtendDirection = AxisExtendDirection.None;
            RadChart1.DefaultView.ChartArea.AxisY.AutoRange = false;
            RadChart1.DefaultView.ChartArea.AxisY.AddRange(0, 100, 10);
            RadChart1.DefaultView.ChartArea.SelectionChanged += new EventHandler<ChartSelectionChangedEventArgs>(ChartArea_SelectionChanged);

            RadChart1.SeriesMappings.Add(sm);
            RadChart1.ItemsSource = data;

            ConfigureZong();
        }

        void ChartArea_SelectionChanged(object sender, ChartSelectionChangedEventArgs e)
        {
            // (sender as ChartArea).SelectedItems.Count is always 1
        }

        private Random rand = new Random(DateTime.Now.Millisecond);

        private void ConfigureZong()
        {
            DataSeries barSeries = GetZong();
            barSeries.Definition.InteractivitySettings.HoverScope = InteractivityScope.Item;
            barSeries.Definition.InteractivitySettings.SelectionScope = InteractivityScope.Item;
            barSeries.Definition.InteractivitySettings.SelectionMode = ChartSelectionMode.Single;

            barSeries.Definition.ShowItemToolTips = true;

            chart2.DataSeries.Add(barSeries);

            chart2.AxisY.Title = "";
            chart2.AxisY.AxisStyles.TitleStyle = Resources["CustomAxisTitleStyle"] as Style;
            chart2.AxisY.ExtendDirection = AxisExtendDirection.None;
            chart2.AxisY.AutoRange = false;
            chart2.AxisY.AddRange(0, 35000, 5000);

        }

        public DataSeries GetZong()
        {
            DataSeries series = new DataSeries();

            for (int i = 4; i > 0; i--)
            {
                DataPoint dataPoint = new DataPoint();
                dataPoint.YValue = rand.Next(20000, 35000);

                DateTime dt = DateTime.Now.AddDays(-i);
                dataPoint.XCategory = dt.ToShortDateString();
                series.Add(dataPoint);
            }

            return series;
        }

    }

    public class ChartData
    {
        public double Y
        {
            get;
            set;
        }
    }
}

Hi ji,

Using external ChartArea like this is not supported by the chart control and may exhibit erroneous behavior. We would suggest you to use second RadChart instance instead of the ChartArea with x:Name="chart2". If you need to customize the default layout, you can set the RadChart.UseDefaultLayout property to false and add your desired layout as content of the RadChart control.

Hope this helps.


All the best,
Freddie
the Telerik team