我有以下样式删除数据点并随机生成我的线系列图的线颜色

<Style x:Key="LineDataPointStyle" 
        TargetType="ChartingToolkit:LineDataPoint">
    <Setter Property="Foreground" Value="DarkGreen"/>
    <Setter Property="IsTabStop" Value="False"/>
    <Setter Property="Width" Value="NaN"/>
    <Setter Property="Height" Value="NaN"/>
    <Setter Property="Background" 
            Value="{Binding RelativeSource={RelativeSource Self}, 
                            Converter={StaticResource ColorBrushConverter}}"/>
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="ChartingToolkit:LineDataPoint">
                <Grid x:Name="Root" Opacity="0"/>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

转换器在哪里：

public class ColorToBrushConverter : IValueConverter
{
    public object Convert(object value, Type targetType, 
        object parameter, System.Globalization.CultureInfo culture)
    {
        return new SolidColorBrush(Utils.GenerateRandomColor());
    }

    public object ConvertBack(object value, Type targetType, 
        object parameter, System.Globalization.CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

这会以随机颜色生成线条,但图例是不同的颜色;既可以由库本身自动生成,也可以通过样式模板调用我的转换器.

如何让图例打印出正确的颜色？

最佳答案 注意：是Killercam问题的答案,已被问到
here.这个问题的答案特别适合他的赏金,所以应他的要求我在这里发表.

在这个答案中,Button控件用于演示如何使用模板.

第一部分.在ControlTemplate中绑定

如果要在ControlTemplate中使用Binding,则应使用以下构造：

<ControlTemplate TargetType="{x:Type SomeControl}">
    <Rectangle Fill="{TemplateBinding Background}" />

引自MSDN：

A TemplateBinding is an optimized form of a Binding for template scenarios, analogous to a Binding constructed with {Binding RelativeSource={RelativeSource TemplatedParent}}.

关于使用TemplateBinding的注意事项

TemplateBinding在模板外或VisualTree属性之外不起作用,因此您甚至无法在模板的触发器中使用TemplateBinding.此外,当应用于Freezable时,TemplateBinding不起作用(主要是出于人为原因),例如VisualBrush.在这种情况下,可以像这样使用Binding：

<FreezableControl Property="{Binding RelativeSource={RelativeSource TemplatedParent},
                                     Path=Background}" />

此外,您始终可以使用TemplateBinding的替代方法：

<Rectangle Fill="{Binding RelativeSource={RelativeSource TemplatedParent},
                          Path=Background}" />

作为另一种可能性,您还可以尝试以下方法：

<Rectangle Fill="{Binding Background, 
                          RelativeSource={RelativeSource AncestorType={x:Type SomeControl}}, 
                          Path=Background}" />

第二部分.有关您的版本的说明

在您的情况下,这可能会导致ControlTemplate中的名称冲突,因为您已经使用Binding背景是为Border.因此,删除它为边框绑定,或使用其他属性,如标记或附加依赖属性绑定背景颜色.

使用示例

取而代之的是ChartingToolkit控件,作为Button控件的基础,因为它更容易展示这种样式的想法.

解决方案1：使用Tag

<Window.Resources>
    <Style x:Key="TestButtonStyle" TargetType="{x:Type Button}">
        <Setter Property="BorderThickness" Value="0" />
        <Setter Property="IsTabStop" Value="False" />

        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type Button}">
                    <!-- Here we are set Tag for Border Background -->
                    <Border Background="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=Tag}" 
                            BorderThickness="{TemplateBinding BorderThickness}">

                        <Grid>
                            <Rectangle Width="24" 
                                       Height="24" 
                                       Fill="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=Background}" 
                                       Stroke="{TemplateBinding BorderBrush}" />

                            <ContentPresenter Content="{TemplateBinding Content}" 
                                              HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
                                              VerticalAlignment="{TemplateBinding VerticalContentAlignment}" />
                        </Grid>
                    </Border>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</Window.Resources>

<Grid>
    <Button Name="TestButton"
            Style="{StaticResource TestButtonStyle}"
            Content="Test"
            HorizontalContentAlignment="Center"
            VerticalContentAlignment="Center"
            Tag="Green"
            Background="Aquamarine"
            Width="100"
            Height="100" />
</Grid>

产量

对于Rectangle,设置两种颜色：Rectangle的默认值,Tag for Border.我觉得这不是一个好的解决方案,原因如下：

>如果Border和Rectangle需要设置不同的值,例如：Background,BorderThickness,BorderBrush等,则一个Tag是不够的.
>有一个名称属性必须明确其目的,一个名称“标记”我们什么也没说.

在这些缺点中可以得出结论,我们应该找到一个替代方案,作为替代方案,我使用带有附加依赖属性的扩展类.

扩展程序类ButtonExt.cs

public static class ButtonExt
{
    #region RectangleBackground Property

    public static readonly DependencyProperty RectangleBackgroundProperty;

    public static void SetRectangleBackground(DependencyObject DepObject, Brush value)
    {
        DepObject.SetValue(RectangleBackgroundProperty, value);
    }

    public static Brush GetRectangleBackground(DependencyObject DepObject)
    {
        return (Brush)DepObject.GetValue(RectangleBackgroundProperty);
    }

    #endregion

    #region RectangleBorderBrush Property

    public static readonly DependencyProperty RectangleBorderBrushProperty;

    public static void SetRectangleBorderBrush(DependencyObject DepObject, Brush value)
    {
        DepObject.SetValue(RectangleBorderBrushProperty, value);
    }

    public static Brush GetRectangleBorderBrush(DependencyObject DepObject)
    {
        return (Brush)DepObject.GetValue(RectangleBorderBrushProperty);
    }

    #endregion       

    #region Button Constructor

    static ButtonExt()
    {
        #region RectangleBackground

        PropertyMetadata BrushPropertyMetadata = new PropertyMetadata(Brushes.Transparent);

        RectangleBackgroundProperty = DependencyProperty.RegisterAttached("RectangleBackground",
                                                            typeof(Brush),
                                                            typeof(ButtonExt),
                                                            BrushPropertyMetadata);

        #endregion

        #region RectangleBorderBrush

        RectangleBorderBrushProperty = DependencyProperty.RegisterAttached("RectangleBorderBrush",
                                                            typeof(Brush),
                                                            typeof(ButtonExt),
                                                            BrushPropertyMetadata);

        #endregion
    }

    #endregion
}

MainWindow.xaml

<Window.Resources>
    <Style x:Key="TestButtonExtensionStyle" TargetType="{x:Type Button}">
        <Setter Property="Width" Value="80" />
        <Setter Property="Height" Value="80" />
        <Setter Property="Background" Value="Green" />
        <Setter Property="BorderBrush" Value="Pink" />
        <Setter Property="BorderThickness" Value="4" />

        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type Button}">
                    <Border Background="{TemplateBinding Background}" 
                            BorderBrush="{TemplateBinding BorderBrush}"
                            BorderThickness="{TemplateBinding BorderThickness}">

                        <Grid>
                            <Rectangle Fill="{TemplateBinding PropertiesExtension:ButtonExt.RectangleBackground}" 
                                       Stroke="{TemplateBinding PropertiesExtension:ButtonExt.RectangleBorderBrush}"
                                       Width="30" 
                                       Height="30" />

                            <ContentPresenter Content="{TemplateBinding Content}" 
                                              HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
                                              VerticalAlignment="{TemplateBinding VerticalContentAlignment}" />
                        </Grid>
                    </Border>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</Window.Resources>

<Grid>
    <Button Style="{StaticResource TestButtonExtensionStyle}"
            PropertiesExtension:ButtonExt.RectangleBackground="Aquamarine"
            PropertiesExtension:ButtonExt.RectangleBorderBrush="Black"
            Content="Test" />
</Grid>

产量

第三部分.设置依赖项属性的值

创建并注册附加的依赖项属性时,必须声明Set和Get方法与他一起使用：

public static void SetRectangleBackground(DependencyObject DepObject, Brush value)
{
    DepObject.SetValue(RectangleBackgroundProperty, value);
}

public static Brush GetRectangleBackground(DependencyObject DepObject)
{
    return (Brush)DepObject.GetValue(RectangleBackgroundProperty);
}

然后与他们合作将如下：

组

ButtonExt.SetRectangleBackground(MyButton, Brushes.Red);

得到

Brush MyBrush = ButtonExt.GetRectangleBackground(MyButton);

但就我们而言,并非如此简单.当我使用附加的依赖属性问题时,更新值不是.但在我们的例子中,属性在模板中,在我的情况下没有更新Button.我试图在Binding和属性声明中设置Mode = TwoWay,UpdateSourceTrigger = PropertyChanged,GetBindingExpression().UpdateTarget(),但它没用.

请注意,对于属性设置新值和模板的通知,属性已更新.也许我错了,你会工作,或者可能是专门制作的,例如为了避免内存泄漏.

在任何情况下,最好不要直接更新依赖属性,并将Model的属性绑定到它,并在ViewModel中设置值.

例：

<Button Style="{StaticResource TestButtonExtensionStyle}"
        adp:ButtonExt.RectangleBackground="{Binding Path=Model.RectBackground,
                                                    Mode=TwoWay, 
                                                    UpdateSourceTrigger=PropertyChanged}"
        adp:ButtonExt.RectangleBorderBrush="{Binding Path=Model.RectBorderBrush,
                                                     Mode=TwoWay, 
                                                     UpdateSourceTrigger=PropertyChanged}" />

其中RectBackground和RectBorderBrush实现INotifyPropertyChanged接口.

作为这种情况的替代方法,不要使用依赖项属性并使用DataTemplate作为控件. DataTemplate是MVVM的理想选择,非常灵活和动态.

例如,使用DataTemplate,您可以看到我的答案：

Make (create) reusable dynamic Views

One ViewModel for UserControl and Window or separate ViewModels