LiveCharts - 填充/描边绑定的 DependencyProperty 不起作用

Question

我正在创建的可重用控件上的 DependencyProperty 存在问题，该控件使用 LiveCharts 绘制单线系列。问题是我要配置 3 个依赖属性；一个是图表的值，一个是系列的填充颜色，最后一个是线条系列的笔触颜色。这是我的 XAML：

<UserControl x:Class="DataAnalyzer.Controls.QuickPlotSingleLogFile2"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
         xmlns:local="clr-namespace:DataAnalyzer.Controls"
         xmlns:lvc="clr-namespace:LiveCharts.Wpf;assembly=LiveCharts.Wpf"
         mc:Ignorable="d" 
         d:DesignHeight="450" d:DesignWidth="800"
         x:Name="parentControl">
<Grid x:Name="Grid_Container">
    <Grid.RowDefinitions>
        <RowDefinition Height="*"></RowDefinition>
    </Grid.RowDefinitions>
    <lvc:CartesianChart Name="ChartFile" 
                        Grid.Row="0" 
                        LegendLocation="None" 
                        DisableAnimations="true" 
                        Hoverable="true" 
                        DataTooltip="{x:Null}" 
                        Margin="10" 
                        BorderBrush="Black">
        <lvc:CartesianChart.Series>
            <lvc:LineSeries x:Name="LineSeries1" 
                            PointGeometry="{x:Null}" 
                            Values="{Binding PlotValues}" 
                            Fill="{Binding FillBrush}" 
                            Stroke="{Binding StrokeBrush}" 
                            AreaLimit="0"></lvc:LineSeries>
        </lvc:CartesianChart.Series>
        <lvc:CartesianChart.AxisX>
            <lvc:Axis Labels=" " Title="Time">
                <lvc:Axis.Separator>
                    <lvc:Separator IsEnabled="False"></lvc:Separator>
                </lvc:Axis.Separator>
            </lvc:Axis>
        </lvc:CartesianChart.AxisX>
    </lvc:CartesianChart>
</Grid>

下面是代码：

public partial class QuickPlotSingleLogFile2 : UserControl, INotifyPropertyChanged
{

    // Formatter for the datetime in the x-axis for any series
    public Func<double, string> DateTimeSeriesFormatter { get; set; }

    #region PlotValues DP

    public ChartValues<double> PlotValues {
        get { return (ChartValues<double>)GetValue(PlotValuesProperty); }
        set { SetValue(PlotValuesProperty, value); }
        }

    public static readonly DependencyProperty PlotValuesProperty = DependencyProperty.Register("PlotValues", typeof(ChartValues<double>), typeof(QuickPlotSingleLogFile2));

    #endregion

    #region FillBrush DP

    public Brush FillBrush
    {
        get { return (Brush)GetValue(FillBrushProperty); }
        set { SetValue(FillBrushProperty, value); }
    }

    public static readonly DependencyProperty FillBrushProperty = DependencyProperty.Register("FillBrush", typeof(Brush), typeof(QuickPlotSingleLogFile2), new PropertyMetadata());

    #endregion

    #region StrokeBrush DP

    public Brush StrokeBrush
    {
        get { return (Brush)GetValue(StrokeBrushProperty); }
        set { SetValue(StrokeBrushProperty, value); }
    }

    public static readonly DependencyProperty StrokeBrushProperty = DependencyProperty.Register("StrokeBrush", typeof(Brush), typeof(QuickPlotSingleLogFile2), new PropertyMetadata(null));

    #endregion

    public QuickPlotSingleLogFile2()
    {
        InitializeComponent();

        Grid_Container.DataContext = this;

    }

    #region INotifyPropertyChanged Members
    public event PropertyChangedEventHandler PropertyChanged;

     protected void OnPropertyChanged([CallerMemberName]string propertyName = null)
    {
        PropertyChangedEventHandler handler = this.PropertyChanged;

        if (handler != null)
        {
            var e = new PropertyChangedEventArgs(propertyName);
            handler(this, e);
        }
    }
    #endregion

}

我的问题是，对于像“Fill”这样的属性，我是否还需要做更多的事情？我配置的 PlotValuesProperty 完全按预期工作——绑定没有问题。但我无法让绑定适用于填充或描边画笔 - 它会以某种方式丢失，并且实时图表提供填充和描边的默认值。此用户控件用于父窗口，数据上下文最终成为我想要的窗口。我检查了调试器以确保数据上下文设置正确，并且它似乎可以工作，因为图表的值设置正确。但是填充/描边发生了一些奇怪的事情。

Answer 1

我想出了这个问题的答案。我不明白为什么，但我没有看到绑定工作的原因是因为我没有在我的主窗口中初始化填充/描边属性。

作为参考，我的主窗口原始代码（被截断以仅显示此自定义控件的相关绑定）是：

public partial class MainWindow
{
    #region Binding QuickPlotValues
    private ChartValues<double> _quickPlotSingleLogFileValues;
    public ChartValues<double> QuickPlotSingleLogFileValues
    {
        get
        {
            return _quickPlotSingleLogFileValues;
        }
        set
        {
            _quickPlotSingleLogFileValues = value;
            OnPropertyChanged("QuickPlotSingleLogFileValues");
        }
    }
    #endregion

    #region Binding QuickPlotFill
    private Brush _quickPlotFill;
    public Brush QuickPlotFill
    {
        get
        {
            return _quickPlotFill;
        }
        set
        {
            _quickPlotFill = value;
            OnPropertyChanged("QuickPlotFill");
        }
    }
    #endregion

    #region Binding QuickPlotStroke
    private Brush _quickPlotStroke;
    public Brush QuickPlotStroke
    {
        get
        {
            return _quickPlotStroke;
        }
        set
        {
            _quickPlotStroke = value;
            OnPropertyChanged("QuickPlotStroke");
        }
    }
    #endregion
}

自定义控件的 XAML 是：

<vm:QuickPlotSingleLogFile2 x:Name="PreviewPlotSingleLogFile2"
                                            Grid.Row="1"
                                            Margin="20"
                                            VerticalAlignment="Stretch"
                                            MinHeight="250"
                                            PlotValues="{Binding QuickPlotSingleLogFileValues}"
                                            FillBrush="{Binding QuickPlotFill}"
                                            StrokeBrush="{Binding QuickPlotStroke}"/>

我将主窗口代码更新为以下内容（初始化填充/描边颜色）：

 #region Binding QuickPlotFill
    private Brush _quickPlotFill = new SolidColorBrush(Colors.Red);
    public Brush QuickPlotFill
    {
        get
        {
            return _quickPlotFill;
        }
        set
        {
            _quickPlotFill = value;
            OnPropertyChanged("QuickPlotFill");
        }
    }
    #endregion

    #region Binding QuickPlotStroke
    private Brush _quickPlotStroke = new SolidColorBrush(Colors.Green);
    public Brush QuickPlotStroke
    {
        get
        {
            return _quickPlotStroke;
        }
        set
        {
            _quickPlotStroke = value;
            OnPropertyChanged("QuickPlotStroke");
        }
    }
    #endregion

突然间它奏效了。