Which version are you running, and which is the exception that you get? Are you making sure that any interaction with the chart is marshalled through the chart's Dispatcher?

-Graham

Here's one way to go about working around the issue with the RTM build. It displays a loading splash in place of the chart until the data is ready.

The Xaml:

<UserControl.Resources>
        <local:TestData x:Key="data" />
        <local:VisibilityConverter x:Key="visibilityConverter" />
    </UserControl.Resources>

    <Grid x:Name="LayoutRoot" Background="White">
        <Border Background="Gray" 
                Visibility="{Binding Source={StaticResource data}, Path=IsLoading, Converter={StaticResource visibilityConverter}}" >
            <TextBlock VerticalAlignment="Center"
                       HorizontalAlignment="Center"
                       Text="Loading"
                       Foreground="White"
                       FontSize="40"
                       />
        </Border>

        <igChart:XamDataChart x:Name="theChart" 
                              Visibility="{Binding Source={StaticResource data}, Path=IsLoaded, Converter={StaticResource visibilityConverter}}">
            <igChart:XamDataChart.Axes>
                <igChart:NumericYAxis x:Name="yAxis" />
                <igChart:CategoryDateTimeXAxis x:Name="dateAxis"
                                               DateTimeMemberPath="Date"
                                               Label="{}{Date:MM/dd/yy hh:mm:ss}"
                                               ItemsSource="{StaticResource data}"/>
            </igChart:XamDataChart.Axes>
            
            <igChart:XamDataChart.Series>
                <igChart:LineSeries x:Name="lineSeries"
                                    XAxis="{Binding ElementName=dateAxis}"
                                    YAxis="{Binding ElementName=yAxis}"
                                    ItemsSource="{StaticResource data}"
                                    ValueMemberPath="Value"
                                    />
            </igChart:XamDataChart.Series>
        </igChart:XamDataChart>
    </Grid>

And the code behind:

public partial class MainPage : UserControl
    {
        public MainPage()
        {
            InitializeComponent();
            ThreadStart start =
                new ThreadStart(DoAddData);
            Thread thread = new Thread(start);
            thread.Start();
        }

        public void DoAddData()
        {
            System.Threading.Thread.Sleep(5000);
            Dispatcher.BeginInvoke(
                AddData);
        }

        public void AddData()
        {
            var testData = Resources["data"] as TestData;

            testData.Add(
                new TestDataItem()
                {
                    Date = DateTime.Now.AddDays(-5),
                    Value = 1
                });
            testData.Add(
                new TestDataItem()
                {
                    Date = DateTime.Now.AddDays(-4),
                    Value = 2
                });
            testData.Add(
                new TestDataItem()
                {
                    Date = DateTime.Now.AddDays(-3),
                    Value = 3
                });
            testData.Add(
                new TestDataItem()
                {
                    Date = DateTime.Now.AddDays(-2),
                    Value = 4
                });
            testData.Add(
                new TestDataItem()
                {
                    Date = DateTime.Now.AddDays(-1),
                    Value = 5
                });
            testData.IsLoading = false;
            testData.IsLoaded = true;
        }
    }

    public class VisibilityConverter
        : IValueConverter
    {

        public object Convert(
            object value, 
            Type targetType, 
            object parameter, 
            System.Globalization.CultureInfo culture)
        {
            if (value is bool && targetType == typeof(Visibility))
            {
                if ((bool)value)
                {
                    return Visibility.Visible;
                }
                else
                {
                    return Visibility.Collapsed;
                }
            }

            return null;
        }

        public object ConvertBack(
           object value, 
           Type targetType, 
           object parameter, 
           System.Globalization.CultureInfo culture)
        {
            throw new NotImplementedException();
        }
    }

    public class TestData
        : ObservableCollection<TestDataItem>
    {
        public TestData()
        {
            IsLoaded = false;
            IsLoading = true;
        }

        private bool _isLoading;
        public bool IsLoading
        {
            get { return _isLoading; }
            set
            {
                _isLoading = value;
                OnPropertyChanged(
                    new PropertyChangedEventArgs("IsLoading"));
            }
        }

        private bool _isLoaded;

        public bool IsLoaded
        {
            get { return _isLoaded; }
            set
            {
                _isLoaded = value;
                OnPropertyChanged(
                    new PropertyChangedEventArgs("IsLoaded"));
            }
        }
    }

    public class TestDataItem
    {
        public DateTime Date { get; set; }
        public double Value { get; set; }
    }

Hope this helps! Let me know if you have any questions.

-Graham

The trial represents the RTM version of the chart where the issue existed. If I can reproduce the issue here I'll see if I can find you a work around for that version. I may not be recalling correctly, but I don't think this issue occurred if the chart initially had some data assigned to it. When you are using RIA services, because the access is asynchronous, you create a case where the chart is displayed before there is data assigned to it. I believe the initial version of the CategoryDateTimeXAxis may have had some issues with this scenario in some situations. You could also try deferring the initial display of the chart until you are notified that the data has arrived. Also, the CategoryXAxis does not exhibit this error, if it is possible to use that axis for your evaluation.

-Graham

Hi Graham,

I have downloaded the trials just a few days ago. The InfragisticsSL4.Controls.Charts.XamDataChart.v10.2.dll shows 10.2.20102.1029 as the file version....