将 WPF 扩展工具包 ColorPicker SelectedColor 属性绑定到 DependencyProperty

Question

我正在尝试将 WPF Extended Toolkit ColorPicker 的 SelectedColor 属性绑定到类型为 SolidColorBrush 的 DependencyProperty。然后，该颜色应该用作画布上/画布中的形状的填充颜色。

这不起作用，据我了解，问题在于 ColorPicker 的 SelectedColor 属性实际上是一个类型为 Color? 的对象。我的问题是，我该如何让它工作？如果我只是通过与事件挂钩的方法在代码中执行此操作，我可以使用SelectedColor.Value，但 AFAIK 不是 XAML 中的选项。

我确实尝试使用常规属性并让类继承自 INotifyPropertyChanged（如 SelectedColor binding doesn't update from ColorPicker to Model），而不是从 DependencyObject，但这也不起作用。

我更喜欢用 Binding 来做这件事，因为我试图在使用 MVVM 的实践中获得更多。我最近才学会如何使用 MVVM，而且我现在更喜欢它，所以我真的很想避免只使用代码隐藏。

XAML：

    <toolkit:ColorPicker x:Name="fillColor" Grid.Column="1" Grid.Row="8" Margin="5" VerticalAlignment="Top" SelectedColor="{Binding Path=FillColor, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" SelectedColorChanged="fillColor_SelectedColorChanged" />
    <toolkit:ColorPicker x:Name="lineColor" Grid.Column="2" Grid.Row="8" Margin="5" VerticalAlignment="Top" />

C#： 私有静态 DependencyProperty FillColorProperty = DependencyProperty.Register("FillColor", typeof(SolidColorBrush), typeof(TuckboxModel), new FrameworkPropertyMetadata(Brushes.Purple));

    private static DependencyProperty LineColorProperty = DependencyProperty.Register("LineColor", typeof(SolidColorBrush),
        typeof(TuckboxModel), new FrameworkPropertyMetadata(Brushes.Black));

public SolidColorBrush FillColor
    {
        get { return (SolidColorBrush)GetValue(FillColorProperty); }
        set
        {
            SetValue(FillColorProperty, value);
        }
    }

    public SolidColorBrush LineColor
    {
        get { return (SolidColorBrush)GetValue(LineColorProperty); }
        set { SetValue(LineColorProperty, value); }
    }

public void CreateBox(Canvas drawingCanvas, TuckboxModel model, double width, double height, double depth, SolidColorBrush shading, SolidColorBrush outline)
    {
        double xOrigin = 50;
        double yOrigin = 450;

        double xCoord = xOrigin;
        double yCoord = yOrigin;
        Shape item;
        double flapSize;
        long count;

        //Remove all previous shapes from Canvas
        drawingCanvas.Children.Clear();

        Path border = new Path();
        border.Stroke = model.LineColor;
        border.StrokeThickness = 1.0;            
        border.Fill = model.FillColor;
        //border.Fill = shading;

        yCoord -= ToPts(depth);
        xCoord += ToPts(depth);

        RectangleGeometry rectangleA = new RectangleGeometry();
        Rect rectA = new Rect(xCoord, yCoord, ToPts(width), ToPts(depth));
        rectangleA.Rect = rectA;

        xCoord += ToPts(width);

        RectangleGeometry rectangleB = new RectangleGeometry();
        Rect rectB = new Rect(xCoord + 3, yCoord, ToPts(depth) - 5, ToPts(depth));
        rectangleB.Rect = rectB;

        xCoord += ToPts(depth);

        RectangleGeometry rectangleC = new RectangleGeometry();
        Rect rectC = new Rect(xCoord + 2, yCoord, ToPts(width) - 4, ToPts(depth) - 2);
        rectangleC.Rect = rectC;

        xCoord += ToPts(width);

        RectangleGeometry rectangleD = new RectangleGeometry();
        Rect rectD = new Rect(xCoord + 2, yCoord, ToPts(depth) - 5, ToPts(depth));
        rectangleD.Rect = rectD;

        xCoord = xOrigin;
        yCoord -= ToPts(height);

        RectangleGeometry rectangleE = new RectangleGeometry();
        Rect rectE = new Rect(xCoord, yCoord, ToPts(depth), ToPts(height));
        rectangleE.Rect = rectE;

        xCoord += ToPts(depth);

        RectangleGeometry rectangleF = new RectangleGeometry();
        Rect rectF = new Rect(xCoord, yCoord, ToPts(width), ToPts(height));
        rectangleF.Rect = rectF;

        xCoord += ToPts(width);

        RectangleGeometry rectangleG = new RectangleGeometry();
        Rect rectG = new Rect(xCoord, yCoord, ToPts(depth), ToPts(height));
        rectangleG.Rect = rectG;

        xCoord += ToPts(depth);

        RectangleGeometry rectangleH = new RectangleGeometry();
        Rect rectH = new Rect(xCoord, yCoord, ToPts(width), ToPts(height));
        rectangleH.Rect = rectH;

        xCoord += ToPts(width);

        RectangleGeometry rectangleI = new RectangleGeometry();
        Rect rectI = new Rect(xCoord, yCoord, ToPts(depth) - 3, ToPts(height));
        rectangleI.Rect = rectI;

        xCoord = xOrigin;
        yCoord -= ToPts(depth);

        RectangleGeometry rectangleJ = new RectangleGeometry();
        Rect rectJ = new Rect(xCoord + 1, yCoord, ToPts(depth) - 2, ToPts(depth));
        rectangleJ.Rect = rectJ;

        xCoord += ToPts(depth);

        RectangleGeometry rectangleK = new RectangleGeometry();
        Rect rectK = new Rect(xCoord, yCoord, ToPts(width), ToPts(depth));
        rectangleK.Rect = rectK;

        xCoord += ToPts(width);

        RectangleGeometry rectangleL = new RectangleGeometry();
        Rect rectL = new Rect(xCoord + 1, yCoord, ToPts(depth) - 2, ToPts(depth));
        rectangleL.Rect = rectL;            

        EllipseGeometry ellipseA = new EllipseGeometry();
        ellipseA.Center = new Point(rectK.Right - (rectK.Width / 2), yCoord);
        ellipseA.RadiusX = rectK.Width / 2;

        if(height < 1.0)
            flapSize = ToPts(height);
        else
            flapSize = 72;

        ellipseA.RadiusY = flapSize;

        GeometryGroup finalShape = new GeometryGroup();
        finalShape.Children.Add(rectangleA);
        finalShape.Children.Add(rectangleB);
        finalShape.Children.Add(rectangleC);
        finalShape.Children.Add(rectangleD);
        finalShape.Children.Add(rectangleE);
        finalShape.Children.Add(rectangleF);
        finalShape.Children.Add(rectangleG);

        finalShape.Children.Add(rectangleH);
        finalShape.Children.Add(rectangleI);
        finalShape.Children.Add(rectangleJ);
        finalShape.Children.Add(rectangleK);
        finalShape.Children.Add(rectangleL);
        finalShape.Children.Add(ellipseA);

        finalShape.FillRule = FillRule.Nonzero;

        border.Data = finalShape;

        drawingCanvas.Children.Add(border);
    }

任何帮助将不胜感激！

Answer 1

我认为Converter 可以解决您的问题。下面是一个转换器类的例子：

using System;
using System.Globalization;
using System.Windows.Data;

namespace SO_app.Converters
{
    public class DebugConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (null == value) {
                return null;
            }
            // For a more sophisticated converter, check also the targetType and react accordingly..
            if (value is Color) {
                Color color = (Color)value;
                return new SolidColorBrush(color);
            }
            // You can support here more source types if you wish
            // For the example I throw an exception

            Type type = value.GetType();
            throw new InvalidOperationException("Unsupported type ["+type.Name+"]");  
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            return value;
        }
    }
}  

然后在您的 xaml 中它看起来像这样：
这是我的项目：

xmlns:converter="clr-namespace:SO_app.Converters"

然后在资源中：

<converter:DebugConverter x:Key="DebugConverter"/>

然后在 xaml 中：

<toolkit:ColorPicker x:Name="fillColor" Grid.Column="1" Grid.Row="8" Margin="5" VerticalAlignment="Top" SelectedColor="{Binding Path=FillColor, Converter={StaticResource DebugConverter}, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" SelectedColorChanged="fillColor_SelectedColorChanged" />  

注意：
类型转换的代码来自这个SO post。
更新：
检查this SO post，表示工具包中有内置转换器