用户控件依赖项属性未更新

Question

我已经为 livechart 创建了一个用户控件，并试图围绕它创建依赖属性。但是依赖项属性没有得到更新。我用谷歌搜索并找到了 answer in Whosebug。所以我一直在四处寻找。我按照答案中提到的步骤进行操作，但我仍然无法更新图表。代码：-

<LiveChart:CartesianChart Grid.Row="1" Background="White">
        <LiveChart:CartesianChart.AxisX>
            <LiveChart:Axis Title="{Binding Path=XAxisTitle, ElementName=chartControl, UpdateSourceTrigger=PropertyChanged}" Labels="{Binding Path=XAxisValues, ElementName=chartControl, UpdateSourceTrigger=PropertyChanged}"/>
        </LiveChart:CartesianChart.AxisX>
        <LiveChart:CartesianChart.AxisY>
            <LiveChart:Axis Title="{Binding Path=YAxisTitle, ElementName=chartControl, UpdateSourceTrigger=PropertyChanged}" LabelFormatter="{Binding Path=Formatter, ElementName=chartControl, UpdateSourceTrigger=PropertyChanged}" MinValue="0"></LiveChart:Axis>
        </LiveChart:CartesianChart.AxisY>
        <LiveChart:CartesianChart.Series>
            <LiveChart:LineSeries Values="{Binding Path=SpectrumChartSeries, ElementName=chartControl, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"></LiveChart:LineSeries>
        </LiveChart:CartesianChart.Series>
    </LiveChart:CartesianChart>

我已将用户控件命名为 chartControl 并使用了 ElementName。我的后端：-

public List<Point> ChartPoints
    {
        get { return (List<Point>)GetValue(ChartPointsProperty); }
        set { SetValue(ChartPointsProperty, value); }
    }

    public static readonly DependencyProperty ChartPointsProperty = DependencyProperty.Register("ChartPoints", typeof(List<Point>), typeof(chartcontrol), new FrameworkPropertyMetadata(new List<Point>(), onChartrPointChange));

    private static void onChartrPointChange(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        var control = d as chartcontrol;
        var points = e.NewValue as List<Point>;
        control.UpdateChart(points);
    }

    private void UpdateChart(List<Point> chartPoints)
    {
        SpectrumChartSeries = new ChartValues<double>();// { 4, 6, 5, 2, 4, 8, 9, 10, 20, 11, 15 };
        SpectrumChartSeries.AddRange(chartPoints.Select(x => x.Y));
        XAxisValues = chartPoints.Select(x => x.X.ToString()).ToList();//new List<string>() { "1", "2", "3", "4", "5" };
        Formatter = value => (value).ToString("N", System.Globalization.CultureInfo.CurrentCulture);
        XAxisTitle = " test title";
        YAxisTitle = "y title";
    }

changed 事件正在命中并且值已更新。但仍然没有反映在图表中。有点困惑。

问题是当我尝试使用 WPF tool Snoop 并单击线系列时，我可以看到图表立即得到更新，

点击前：-

点击后：-

Answer 1

发布答案以帮助像我这样的人。我能够找到 this blog 帮助我的答案。正如他们所提到的，我需要在 Xaml.

中添加数据上下文

LiveChart:CartesianChart Grid.Row="1" Background="White" DataContext="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=local:LiveChartControl}}">
        <LiveChart:CartesianChart.AxisX>
            <LiveChart:Axis Title="{Binding Path=XAxisTitle, Mode=TwoWay}" Labels="{Binding Path=XAxisValues, Mode=TwoWay}" MinValue="0"/>
        </LiveChart:CartesianChart.AxisX>
        <LiveChart:CartesianChart.AxisY>
            <LiveChart:Axis Title="{Binding Path=YAxisTitle, Mode=TwoWay}" LabelFormatter="{Binding Path=Formatter, Mode=TwoWay}" MinValue="0"></LiveChart:Axis>
        </LiveChart:CartesianChart.AxisY>
        <LiveChart:CartesianChart.Series>
            <LiveChart:LineSeries Values="{Binding Path=ChartPointsInChartValues, Mode=TwoWay}"/>
            <LiveChart:VerticalLineSeries Values="{Binding Path=EnergyLineChartValues , Mode=TwoWay}"/>
        </LiveChart:CartesianChart.Series>
    </LiveChart:CartesianChart>

这现在开始起作用了。

用户控件依赖项属性未更新

User control Dependency property is not getting updated

c#

wpf

xaml

livecharts

用户控件依赖项 属性 未更新

User control Dependency property is not getting updated

c#

wpf

xaml

livecharts

用户控件依赖项属性未更新