绑定到DevExpress StockSeries2D图表

Question

我正在尝试将ViewModel中的ObservableCollection数据绑定到View中的Devexpress 2D Stock Chart.我知道VM绑定了View的DataContext,因为我将窗口的Title绑定到VM中的属性,并且在运行程序时它是正确的.该集合被正确实例化,我可以看到所有对象都已创建,具有值,并被添加到集合中.

图表信息没有显示.该图表显示的不是应该绑定到它的信息.我猜它与我的XAML中的一行有关,但我只是不知道它是什么.

这是输出中的错误:

System.Windows.Data错误:40:BindingExpression路径错误:'对象'''ChartElementPanel'(Name ='')'上找不到'快照'属性.BindingExpression:路径= DataContext.Snapshots; DataItem ='ChartElementPanel'(Name =''); target元素是'StockSeries2D'(HashCode = 24500892); target属性是'DataSource'(类型'Object')

DevExpress版本是10.1.9

编辑:我想我知道问题出在哪里.StockSeries2D DataContext = DevExpress.Xpf.Charts.ChartElementPanel所以当我使用

DataSource="{Binding Path=DataContext.Snapshots}"

它确实指向DevExpress.Xpf.Charts.ChartElementPanel,因为它不包含Snapshots属性,所以会引发错误.

XAML:

    <Grid>
    <Grid.RowDefinitions>
        <RowDefinition Height="200" />
        <RowDefinition Height="50" />
    </Grid.RowDefinitions>
    <dxc:ChartControl Name="chartControl1">
        <dxc:ChartControl.Diagram>
            <dxc:XYDiagram2D>
                <dxc:XYDiagram2D.Series>
                    <dxc:StockSeries2D DataSource="{Binding DataContext.Snapshots}" HighValueDataMember="High" LowValueDataMember="Low" CloseValueDataMember="Last" ArgumentScaleType="DateTime" ArgumentDataMember="TimeStamp">

                        <dxc:StockSeries2D.PointOptions>
                            <dxc:PointOptions dxc:FinancialSeries2D.ValueToDisplay="HighValue" />
                        </dxc:StockSeries2D.PointOptions>

                        <dxc:StockSeries2D.Model>
                            <dxc:ArrowsStock2DModel />
                        </dxc:StockSeries2D.Model>
                    </dxc:StockSeries2D>
                </dxc:XYDiagram2D.Series>

                <!--Region #Axis X-->
                <dxc:XYDiagram2D.AxisX>
                    <dxc:AxisX2D>
                        <dxc:AxisX2D.DateTimeOptions>
                            <dxc:DateTimeOptions Format="ShortTime" />
                        </dxc:AxisX2D.DateTimeOptions>
                    </dxc:AxisX2D>
                </dxc:XYDiagram2D.AxisX>
                <!-- End Rgion -->

                <!-- region #AxisY -->
                <dxc:XYDiagram2D.AxisY>
                    <dxc:AxisY2D>
                        <dxc:AxisY2D.Range>
                            <dxc:AxisRange dxc:AxisY2D.AlwaysShowZeroLevel="False" />
                        </dxc:AxisY2D.Range>
                    </dxc:AxisY2D>
                </dxc:XYDiagram2D.AxisY>

                <!--End Rgion-->
            </dxc:XYDiagram2D>
        </dxc:ChartControl.Diagram>
    </dxc:ChartControl>
</Grid>

视图模型:

    public class MainWindowViewModel : INotifyPropertyChanged
{
    ObservableCollection<ISnapShot> _snapShots;
    string _windowTitle;

    public MainWindowViewModel()
    {
        _snapShots = new ObservableCollection<ISnapShot>();
        LoadSnapshots();
        WindowTitle = Snapshots.First().Symbol;
    }

    public ObservableCollection<ISnapShot> Snapshots
    {
        get { return _snapShots; }
    }

    public String WindowTitle
    {
        get { return _windowTitle; }
        set { _windowTitle = value; OnPropertyChanged("WindowTitle"); }
    }

    private void AddSnapshot(ISnapShot snapshot)
    {
        _snapShots.Add(snapshot);
    }

    private void LoadSnapshots()
    {
        int counter = 0;

        while (counter < 5)
        {
            ISnapShot s = new Snapshot()
            {
                TimeStamp = DateTime.Now,
                Symbol = "XYZ",
                High = (counter + 1) * 5,
                Low = (counter + 1) * 2,
                Last = (counter + 1) * 3
            };

            _snapShots.Add(s);
            counter++;
            Thread.Sleep(1000);
        }

    }

    public event PropertyChangedEventHandler PropertyChanged;
    void OnPropertyChanged(string prop)
    {
        if (PropertyChanged != null)
            PropertyChanged(this, new PropertyChangedEventArgs(prop));
    }
}

视图:

    public partial class MainWindow : Window
{
    private MainWindowViewModel _vm;


    public MainWindow(MainWindowViewModel vm)
    {
        InitializeComponent();
        _vm = vm;
        this.DataContext = _vm;
    }
}

应用程序:

public partial class App : Application
{
    private void OnStartup(object sender, StartupEventArgs e)
    {
        MainWindowViewModel vm = new MainWindowViewModel();
        Views.MainWindow view = new Views.MainWindow(vm); 
        view.Show();
    }
}

Answer 1

我想到了.由于StockSeries2D的DataContext未指向Window的DataContext

<dxc:StockSeries2D DataContext="DevExpress.Xpf.Charts.ChartElementPanel"

我需要设置DataSource以使用Window的DataContext

<dxc:StockSeries2D DataSource="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type Window}}, Path=DataContext.Snapshots}"