如何从 Material Design for XAML 覆盖 ComboBox ToggleButton？

Question

我是 WPF 的新手。 我对覆盖 MaterialDesignComboBoxToggleButton 有疑问 风格。我想用自己的替换“模板”设置器，但我的控制模板中的内容总是被忽略。为什么会这样？使用其他样式我没有这个问题。

下面的代码演示了我需要什么。

Overriedes.xaml

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<ResourceDictionary.MergedDictionaries>
    <ResourceDictionary Source="pack://application:,,,/MaterialDesignThemes.Wpf;component/Themes/MaterialDesignTheme.ComboBox.xaml" />
</ResourceDictionary.MergedDictionaries>

<Style BasedOn="{StaticResource MaterialDesignComboBoxToggleButton}" TargetType="{x:Type ToggleButton}">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type ToggleButton}">
                <TextBlock FontSize="50" FontWeight="Bold">$$</TextBlock>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

App.xaml

<Application x:Class="Wpf.App"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         
         xmlns:local="clr-Wpf" xmlns:materialDesign="http://materialdesigninxaml.net/winfx/xaml/themes"
         StartupUri="Views/MainWindow.xaml">
<Application.Resources>
    <ResourceDictionary>
        <ResourceDictionary.MergedDictionaries>
            <materialDesign:CustomColorTheme BaseTheme="Light" PrimaryColor="#FFD8E1FF" SecondaryColor="#FFD8E1FF" />
            <ResourceDictionary Source="pack://application:,,,/MaterialDesignThemes.Wpf;component/Themes/MaterialDesignTheme.Defaults.xaml" />
            <ResourceDictionary Source="/Overrides.xaml" />
        </ResourceDictionary.MergedDictionaries>
        
    </ResourceDictionary>
</Application.Resources>

Answer 1

将相同的资源键添加到您的自定义样式中，如下所示：

<Style 
    x:Key="MaterialDesignComboBoxToggleButton"
    BasedOn="{StaticResource MaterialDesignComboBoxToggleButton}" 
    TargetType="{x:Type ToggleButton}">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type ToggleButton}">
                <TextBlock FontSize="50" FontWeight="Bold">$$</TextBlock>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

并且你不需要在Overrides.xaml文件中添加这样的资源：

<ResourceDictionary.MergedDictionaries>
    <ResourceDictionary Source="pack://application:,,,/MaterialDesignThemes.Wpf;component/Themes/MaterialDesignTheme.ComboBox.xaml" />
</ResourceDictionary.MergedDictionaries>

因为您在App.xaml 文件中添加的MaterialDesignTheme.Defaults.xaml 已经包含了MDIX 资源。