使用linq创建xamdatachart

Question

我使用Silverlight和Infragistic开发项目作为控件来创建使用数据库数据的数据图表。

我使用论坛建议的Linq，MainPage.xaml.cs

               private void studentDomainDataSource_LoadedData(object sender, LoadedDataEventArgs e)
    {
        if (e.HasError)
        {
            System.Windows.MessageBox.Show(e.Error.ToString(), "Load Error", System.Windows.MessageBoxButton.OK);
            e.MarkErrorAsHandled();
        }
        else
        {
            var ChartData =
                (from std in e.Entities
                 group std by (std as Student).ProgramCode into program
                 select new ChartData
                {
                    ProgrammName = (program.First() as Student).Programme.ProgramName,
                    StudentsCount = program.Count()
                }).ToList();
            xamDataChart1.DataContext = ChartData;
        }
    }
}

public class ChartData
{
    public string ProgrammName { get; set; }
    public int StudentsCount { get; set; }
}

这里是MainPage.xaml

<UserControl x:Class="ChartWithRIA.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="400" xmlns:riaControls="clr-    namespace:System.Windows.Controls;assembly=System.Windows.Controls.DomainServices"     xmlns:my="clr-namespace:ChartWithRIA.Web" xmlns:ig="http://schemas.infragistics.com/xaml">

   <Grid x:Name="LayoutRoot" Background="White">
    <riaControls:DomainDataSource
        AutoLoad="True" 
        d:DesignData="{d:DesignInstance my:Student, CreateList=true}"
        Height="0"
        LoadedData="studentDomainDataSource_LoadedData" 
        Name="studentDomainDataSource"
        QueryName="GetStudentsQuery" 
        Width="0">
        <riaControls:DomainDataSource.DomainContext>
            <my:StudentsProgramDomainContext />
        </riaControls:DomainDataSource.DomainContext>
    </riaControls:DomainDataSource>

    <ig:XamDataChart
        Name="xamDataChart1">

        <ig:XamDataChart.Axes>
            <ig:CategoryXAxis
                x:Name="xAxis"
                ItemsSource="{Binding}"
                Label="{}{ProgrammName}"/>

            <ig:NumericYAxis
                x:Name="yAxis"/>
        </ig:XamDataChart.Axes>

        <ig:XamDataChart.Series>
            <ig:LineSeries
                ItemsSource="{Binding}"
                XAxis="{Binding ElementName=xAxis}"
                YAxis="{Binding ElementName=yAxis}"
                ValueMemberPath="StudentsCount"/>
        </ig:XamDataChart.Series>

    </ig:XamDataChart>
    </Grid>
  </UserControl>

构建此解决方案后，没有出现错误，但图表未显示。仅显示布局。 有谁知道我的项目发生了什么或有什么问题？ 提前谢谢。