.net - WPF:从 UserControl 转换为 CustomControl

Question

我有一个 WPF UserControl - SegmentConrol , 表示一行带有一些文本和一个显示方向 (>) 的数组。

因为我必须自定义此控件样式，所以我决定切换到 CustomControl，因为我读到它在某种程度上更好...

现在，我在从 UC 切换到 CC 时遇到了一些“麻烦”。

特别是，不知道将<UserControl.Resources>放在哪里部分。

如果有任何专家可以给我建议，欢迎他们。

这是我的用户控件:

<UserControl x:Class="MyNamespace.ctlWpfPlanDeLigne.SegmentControl"
             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" 
             mc:Ignorable="d" 
             xmlns:local="clr-namespace:MyNamespace.ctlWpfPlanDeLigne"
             d:DesignHeight="300" d:DesignWidth="300"
             x:Name="ParentSegmentControl">
    <UserControl.Resources>
        <local:VisibilityConverter x:Key="VisibilityConverter"/>
        <local:BoolToVisibilityConverter x:Key="BoolToVisibilityConverter"/>
        <local:SegmentToStringConverter x:Key="SegmentToStringConverter"/>
    </UserControl.Resources>
    <Canvas Background="Transparent">
        <Line x:Name="line"              
              X1="{Binding ElementName=ParentSegmentControl, Path=X1}"
              Y1="{Binding ElementName=ParentSegmentControl, Path=Y1}"
              X2="{Binding ElementName=ParentSegmentControl, Path=X2}"
              Y2="{Binding ElementName=ParentSegmentControl, Path=Y2}"  IsHitTestVisible="True"/>

        <Label x:Name="label" 
               Foreground="{Binding ElementName=ParentSegmentControl, Path=LabelForeground}" 
               Background="{Binding ElementName=ParentSegmentControl, Path=LabelBackground}"
               Visibility="{Binding ElementName=ParentSegmentControl, Path=IsLabelUsed, Converter={StaticResource BoolToVisibilityConverter}}"
               >
            <Label.Effect>
                <DropShadowEffect BlurRadius="2" Color="White" Opacity="1" RenderingBias="Performance" ShadowDepth="0" />
            </Label.Effect>
        </Label>
        <Polygon Name="arrow" Visibility="{Binding ElementName=ParentSegmentControl, Path=IsArrowUsed, Converter={StaticResource BoolToVisibilityConverter}}"/>
    </Canvas>
</UserControl>

下面是Themes/Generic.xaml新 CustomControl 的文件我重构了旧的 UserControl:

<ResourceDictionary
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="clr-namespace:MyNamespace.ctlWpfPlanDeLigne">

    <Style TargetType="{x:Type local:SegmentControl}">
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type local:SegmentControl}">
                    <Canvas Background="Transparent">
                        <Line x:Name="line"...

                        <Label x:Name="label"...
                        <Polygon x:Name="arrow" ...
                    </Canvas>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</ResourceDictionary>

编辑:

用代码做什么

    public SegmentControl()
    {
        this.line.StrokeDashCap = PenLineCap.Round;
        this.arrow.StrokeLineJoin = PenLineJoin.Round;
        this.Background = Brushes.Transparent;
    }

当this.line或 this.arrow没有定义？谢谢。

编辑 2

通用.XAML:

<Style TargetType="{x:Type local:SegmentControl}">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type local:SegmentControl}">
                <Canvas Background="Transparent">
                    <Border Background="{TemplateBinding Background}"
                        BorderBrush="{TemplateBinding BorderBrush}"
                        BorderThickness="{TemplateBinding BorderThickness}">
                    </Border>
                    <Line x:Name="PART_line"
                          X1="{Binding ElementName=ParentSegmentControl, Path=X1}"
                          Y1="{Binding ElementName=ParentSegmentControl, Path=Y1}"
                          X2="{Binding ElementName=ParentSegmentControl, Path=X2}"
                          Y2="{Binding ElementName=ParentSegmentControl, Path=Y2}"
                          IsHitTestVisible="True"/>

                    <Label x:Name="PART_label"
                           Foreground="{Binding ElementName=ParentSegmentControl, Path=LabelForeground}"
                           Background="{Binding ElementName=ParentSegmentControl, Path=LabelBackground}"
                           Visibility="{Binding ElementName=ParentSegmentControl, Path=IsLabelUsed, Converter={StaticResource BoolToVisibilityConverter}}">
                        <Label.Effect>
                            <DropShadowEffect BlurRadius="2" Color="White" Opacity="1" RenderingBias="Performance" ShadowDepth="0" />
                        </Label.Effect>
                    </Label>
                    <Polygon x:Name="PART_arrow" 
                             Visibility="{Binding ElementName=ParentSegmentControl, Path=IsArrowUsed, Converter={StaticResource BoolToVisibilityConverter}}"/>
                </Canvas>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>  

.cs:

    public override void OnApplyTemplate()
    {
        base.OnApplyTemplate();

        this.line = this.FindName("PART_line") as Line;      // null
        this.arrow = this.FindName("PART_arrow") as Polygon; // null
        this.label = this.FindName("PART_label") as Label;   // null

        this.line.StrokeDashCap = PenLineCap.Round;
        this.arrow.StrokeLineJoin = PenLineJoin.Round;
    }

Answer 1

我不明白为什么不能直接将它们放入资源字典中？然后它们可以被其他样式/模板重复使用。

 <ResourceDictionary
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:MyNamespace.ctlWpfPlanDeLigne">

            <local:VisibilityConverter x:Key="VisibilityConverter"/>
            <local:BoolToVisibilityConverter x:Key="BoolToVisibilityConverter"/>
            <local:SegmentToStringConverter x:Key="SegmentToStringConverter"/>

    <Style....

编辑:

针对您的第二个问题，您需要在代码中执行此操作:

Line line = this.FindName("line") as Line;
Polygon arrow = this.FindName("arrow") as Polygon;

虽然通常的做法是用“PART_”命名您的控件，所以它显示

Line line = this.FindName("PART_line") as Line;
Polygon arrow = this.FindName("PART_arrow") as Polygon;

此名称对应于 xaml 中给出的 x:Name..

编辑 3:

你需要像这样确保你的窗口知道你的资源字典:

 <Window.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <ResourceDictionary Source="/Namespace.Controls;component/Themes/CustomControls.xaml" />
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
    </WindowResources>