Question

关于用于UWP的Telerik UI控件的两个问题

在UWP应用中，我有一个RadCartesianChart控件。具有ScatterLine和ScatterArea系列。将ItemsSource设置为ObservableCollection，包含的对象是具有X和Y属性的简单对象，具有INotifyPropertyChanged接口，因此，当X或Y属性更新时，它们将触发更改值事件。 X和Y值绑定都设置为ScatterLineSeries中的相应属性

现在，我知道源是一个ObservableCollection，当我向集合中添加或删除点时，图表控件会自动更新，但是当我修改点的值时如何刷新图表？控制重新查询数据源？下面是数据点类。

public class DataPoint : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler PropertyChanged;

    private decimal x;
    private ComplexDecimal y;

    public decimal X { get => x; set { x = value; PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("X")); } }
    public ComplexDecimal Y
    {
        get => y; set
        {
            y = value;
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("Y"));
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("PhaseDegDouble"));
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("dBV"));
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("dBm"));
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("dBSPL"));
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("Magnitude"));
        }
    }

    public double PhaseDegDouble { get => Y.PhaseDegDouble; }
    public double dBV { get => Y.TodBV; }
    public double dBSPL { get => Y.TodBSPL; }
    public double dBm { get => Y.TodBm; }
    public double Magnitude { get => Convert.ToDouble(Y.Magnitude); }

}

所以我有一个函数对象，带有一个字段ObservableCollection Data 我制作了一个ScatterLineSeries。

var lineMag = new ScatterLineSeries()
{
ItemsSource = function.Data,
XValueBinding = new PropertyNameDataPointBinding("X"),
YValueBinding = new PropertyNameDataPointBinding("dBV"),
};

并使用
将其添加到图表中 rcChart.Series.Add(lineMag);

如果我这样做：

function.Data.Add(new DataPoint(){X=30,Y=new ComplexDecimal(1,1)});

点已添加。但是如果我这样做：

function.Data[0].Y = new ComplexDecimal(1,1);

图表不更新。修改现有的DataPoint时如何更新图表？（ComplexDecimal只是实数部分和imag部分都使用十进制类型的复数结构）

旁边还有一个小问题，使用ScatterArea，面积从0填充到值，但是对于我的数据，我的数值为负，所以填充的区域从曲线到顶部，我想从曲线为negativeInfinity。谢谢！

Answer 1

由于您的代码样本仍然不完整。我只是做了一个简单的代码示例进行测试。当绑定在“ RadCartesianChart”控件上工作时，我随后从集合中更新了“ XValue”和“ YValue”。这样就没问题了该图表将被更新。

请参阅我的代码示例：

<Grid>
    <telerikChart:RadCartesianChart x:Name="scatterLineSeries">
        <telerikChart:RadCartesianChart.VerticalAxis>
            <telerikChart:LinearAxis/>
        </telerikChart:RadCartesianChart.VerticalAxis>
        <telerikChart:RadCartesianChart.HorizontalAxis>
            <telerikChart:LinearAxis/>
        </telerikChart:RadCartesianChart.HorizontalAxis>

        <telerikChart:ScatterLineSeries ItemsSource="{Binding}">
            <telerikChart:ScatterLineSeries.XValueBinding>
                <telerikChart:PropertyNameDataPointBinding PropertyName="XValue"/>
            </telerikChart:ScatterLineSeries.XValueBinding>
            <telerikChart:ScatterLineSeries.YValueBinding>
                <telerikChart:PropertyNameDataPointBinding PropertyName="YValue"/>
            </telerikChart:ScatterLineSeries.YValueBinding>
        </telerikChart:ScatterLineSeries>
    </telerikChart:RadCartesianChart>

    <Button Content="update" Click="Button_Click"></Button>
</Grid>

public sealed partial class MainPage : Page
{
    ObservableCollection<Data> sampleData;
    public MainPage()
    {
        this.InitializeComponent();
        sampleData = new ObservableCollection<Data>();
        sampleData.Add(new Data() { XValue = 2, YValue = 3 });
        sampleData.Add(new Data() { XValue = 3, YValue = 4 });
        sampleData.Add(new Data() { XValue = 4, YValue = 5 });
        sampleData.Add(new Data() { XValue = 5, YValue = 6 });
        sampleData.Add(new Data() { XValue = 6, YValue = 5 });
        sampleData.Add(new Data() { XValue = 7, YValue = 4 });
        sampleData.Add(new Data() { XValue = 8, YValue = 3 });
        sampleData.Add(new Data() { XValue = 9, YValue = 4 });
        sampleData.Add(new Data() { XValue = 10, YValue = 5 });
        sampleData.Add(new Data() { XValue = 11, YValue = 4 });
        sampleData.Add(new Data() { XValue = 12, YValue = 3 });
        sampleData.Add(new Data() { XValue = 13, YValue = 2 });
        sampleData.Add(new Data() { XValue = 14, YValue = 1 });

        this.scatterLineSeries.DataContext = sampleData;
    }

    private void Button_Click(object sender, RoutedEventArgs e)
    {
        sampleData[0].XValue = 10;
        sampleData[0].YValue = 5;
    }
}

public class Data : INotifyPropertyChanged
{
    private double xValue;
    public double XValue
    {
        get => xValue;
        set
        {
            xValue = value;
            PropertyChanged?.Invoke(this,new PropertyChangedEventArgs("XValue"));
        }
    }

    private double yValue;
    public double YValue
    {
        get => yValue;
        set
        {
            yValue = value;
            PropertyChanged?.Invoke(this,new PropertyChangedEventArgs("YValue"));
        }
    }
    public event PropertyChangedEventHandler PropertyChanged;
}

如何刷新ScatterLineSeries？

1 个答案: