如何在WPF Toolkit AreaSeries图表上显示数据

我正在使用WPF Toolkit在AreaSeries图表上显示数据，但它没有出现。不知道我做错了什么。请提供帮助/建议。

以下是xaml代码：

<Window xmlns:chart="clr-namespace:System.Windows.Controls.DataVisualization.Charting;assembly=System.Windows.Controls.DataVisualization.Toolkit"
x:Class="GRAPHPrototype.MainWindow"
    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"
    xmlns:local="clr-namespace:GRAPHPrototype"
    mc:Ignorable="d"
    Title="MainWindow" Height="350" Width="525">
<Grid>       
    <chart:Chart Name="chart1">            
    </chart:Chart>
</Grid>

而C#代码：

public partial class MainWindow : Window
{
    static List<Ready4LOS> Ready4LOS = new List<Data.Ready4LOS>();
    public MainWindow()
    {
        InitializeComponent();
        InitChart();
        SampleData();
        chart1.DataContext = Ready4LOS;
    }
    private void SampleData()
    {
        Ready4LOS.Add(new Data.Ready4LOS() { Case = 5, Time = DateTime.Now.AddMinutes(-75) });
        Ready4LOS.Add(new Data.Ready4LOS() { Case = 15, Time = DateTime.Now.AddMinutes(-65) });
        Ready4LOS.Add(new Data.Ready4LOS() { Case = 5, Time = DateTime.Now.AddMinutes(-55) });
        Ready4LOS.Add(new Data.Ready4LOS() { Case = 8, Time = DateTime.Now.AddMinutes(-45) });
        Ready4LOS.Add(new Data.Ready4LOS() { Case = 22, Time = DateTime.Now.AddMinutes(-35) });
        Ready4LOS.Add(new Data.Ready4LOS() { Case = 35, Time = DateTime.Now.AddMinutes(-25) });
        Ready4LOS.Add(new Data.Ready4LOS() { Case = 4, Time = DateTime.Now.AddMinutes(-05) });
    }
    private void InitChart()
    {
        System.Windows.Data.Binding indi = new System.Windows.Data.Binding("Case");
        System.Windows.Data.Binding dep = new System.Windows.Data.Binding("Time");
        AreaSeries ares = new AreaSeries();
        ares.IndependentValueBinding = indi;
        ares.DependentValueBinding = dep;
        DateTimeAxis dta = new DateTimeAxis();
        dta.Interval = 10;
        dta.IntervalType = DateTimeIntervalType.Minutes;
        dta.Title = "Time";
        dta.Orientation = AxisOrientation.X;
        dta.Minimum = DateTime.Now.AddMinutes(-80);
        dta.Maximum = DateTime.Now;
        LinearAxis yaxis = new LinearAxis();
        yaxis.Minimum = 0;
        yaxis.Interval = 2;
        yaxis.Title = "Case";
        yaxis.Orientation = AxisOrientation.Y;
        chart1.Axes.Add(yaxis);
        chart1.Axes.Add(dta);
        chart1.Series.Add(ares);
    }
}

我有这种格式的输入数据

class Ready4LOS : INotifyPropertyChanged
{
    int _case;
    DateTime _time;
    public int Case
    {
        get
        {
            return _case;
        }
        set
        {
            _case = value;
            NotifyPropertyChanged("Case");
        }
    }
    public DateTime Time
    {
        get
        {
            return _time;
        }
        set
        {
            _time = value;
            NotifyPropertyChanged("Time");
        }
    }
    public event PropertyChangedEventHandler PropertyChanged;
    private void NotifyPropertyChanged(String info)
    {
        if (PropertyChanged != null)
        {
            PropertyChanged(this, new PropertyChangedEventArgs(info));
        }
    }
}