为什么我在Generic.xaml中的样式不起作用? [英] Why is my style in Generic.xaml not working?

问题描述

我正在清理App.xaml，并将某些样式移到Generic.xaml中.但是，这些样式没有任何作用.为什么?为了使App.xaml整洁，这是正确的做法吗?

I'm cleaning up App.xaml and moved some styles into Generic.xaml. But then, these styles don't have any effect. Why? Is this correct thing to do to make App.xaml tidy?

编辑(包括一些源代码):

EDIT (to include some source code):

目标是重新设置WPF DataGrid的样式，以使滚动条从上到下，从左到右运行(默认样式不包括行和列标题).

The goal is to restyle WPF DataGrid to make the scrollbars run from top to bottom and from left to right (default style excludes row and column header).

当我将样式放在App.xaml中时，样式正在工作.因为这是一大段代码，所以我想将其从App.xaml中移到/Themes/DataGridEx.xaml中.顺便说一下，DataGridEx是从WPF DataGrid派生的扩展类.

The style is working when I put it in App.xaml. Because it's a big chunk of code, I'd like to move it out of App.xaml into /Themes/DataGridEx.xaml. By the way, DataGridEx is my extended class derived from WPF DataGrid.

这是我的DataGrid.xaml:

This is my DataGrid.xaml:

<ControlTemplate x:Key="SelectAllButtonTemplate" TargetType="{x:Type Button}">
    <Grid>
        <Rectangle x:Name="Border"
             Fill="{DynamicResource {x:Static SystemColors.ControlBrushKey}}" 
             SnapsToDevicePixels="True" />
        <Polygon x:Name="Arrow"
           HorizontalAlignment="Right"
           VerticalAlignment="Bottom"
           Margin="8,8,3,3"
           Opacity="0.15"
           Fill="Black"
           Stretch="Uniform"
           Points="0,10 10,10 10,0" />
    </Grid>
    <ControlTemplate.Triggers>
        <Trigger Property="IsMouseOver" Value="True">
            <Setter TargetName="Border" Property="Stroke" Value="{DynamicResource {x:Static SystemColors.ControlDarkBrushKey}}" />
        </Trigger>
        <Trigger Property="IsPressed" Value="True">
            <Setter TargetName="Border" Property="Fill" Value="{DynamicResource {x:Static SystemColors.ControlDarkBrushKey}}" />
        </Trigger>
        <Trigger Property="IsEnabled" Value="False">
            <Setter TargetName="Arrow" Property="Visibility" Value="Collapsed" />
        </Trigger>
    </ControlTemplate.Triggers>
</ControlTemplate>

<Style TargetType="{x:Type local:DataGridEx}" x:Key="{x:Type local:DataGridEx}">
    <Setter Property="Background"
            Value="{DynamicResource {x:Static SystemColors.ControlBrushKey}}"/>
    <Setter Property="Foreground"
            Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
    <Setter Property="BorderBrush" Value="#FF688CAF" />
    <Setter Property="BorderThickness" Value="1" />
    <Setter Property="RowDetailsVisibilityMode" Value="VisibleWhenSelected" />
    <Setter Property="ScrollViewer.CanContentScroll"
            Value="true"/>
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type local:DataGridEx}">
                <Border Background="{TemplateBinding Background}"
              BorderBrush="{TemplateBinding BorderBrush}"
              BorderThickness="{TemplateBinding BorderThickness}"
              SnapsToDevicePixels="True"
              Padding="{TemplateBinding Padding}">
                    <ScrollViewer   Focusable="false"
                        Name="DG_ScrollViewer">
                        <ScrollViewer.Template>
                            <ControlTemplate TargetType="{x:Type ScrollViewer}">
                                <Grid>
                                    <Grid.RowDefinitions>
                                        <RowDefinition Height="Auto"/>
                                        <RowDefinition Height="*"/>
                                        <RowDefinition Height="Auto"/>
                                    </Grid.RowDefinitions>

                                    <Grid.ColumnDefinitions>
                                        <ColumnDefinition Width="Auto"/>
                                        <ColumnDefinition Width="*"/>
                                        <ColumnDefinition Width="Auto"/>
                                    </Grid.ColumnDefinitions>

                                    <!--Left Column Header Corner -->
                                    <Button Command="{x:Static local:DataGridEx.SelectAllCommand}"
                        Width="{Binding RelativeSource={RelativeSource AncestorType={x:Type local:DataGridEx}}, Path=CellsPanelHorizontalOffset}"
                        Template="{StaticResource SelectAllButtonTemplate}"
                        Focusable="false"
                        Visibility="{Binding RelativeSource={RelativeSource AncestorType={x:Type local:DataGridEx}}, Path=HeadersVisibility, Converter={x:Static local:DataGridEx.HeadersVisibilityConverter}, ConverterParameter={x:Static DataGridHeadersVisibility.All}}" />
                                    <!--Column Headers-->
                                    <DataGridColumnHeadersPresenter Grid.Column="1" 
                                                   x:Name="PART_ColumnHeadersPresenter"
                                                   Visibility="{Binding RelativeSource={RelativeSource AncestorType={x:Type local:DataGridEx}}, Path=HeadersVisibility, Converter={x:Static DataGrid.HeadersVisibilityConverter}, ConverterParameter={x:Static DataGridHeadersVisibility.Column}}"/>

                                    <!--DataGrid content-->
                                    <ScrollContentPresenter x:Name="PART_ScrollContentPresenter" Grid.Row="1" Grid.ColumnSpan="2" CanContentScroll="{TemplateBinding CanContentScroll}" />

                                    <!-- Changed Grid.Row="1" to Grid.Row="0" Grid.RowSpan="2" to make the scrollbar start from top -->
                                    <ScrollBar Grid.Row="0" Grid.RowSpan="2" Grid.Column="2" Name="PART_VerticalScrollBar"
                                         Orientation="Vertical"
                                         Maximum="{TemplateBinding ScrollableHeight}"
                                         ViewportSize="{TemplateBinding ViewportHeight}"
                                         Value="{Binding Path=VerticalOffset, RelativeSource={RelativeSource TemplatedParent}, Mode=OneWay}"
                                         Visibility="{TemplateBinding ComputedVerticalScrollBarVisibility}"/>

                                    <!--Grid Grid.Row="2" Grid.Column="1">
                  <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="{Binding RelativeSource={RelativeSource AncestorType={x:Type dg:DataGrid}}, Path=NonFrozenColumnsViewportHorizontalOffset}"/>
                    <ColumnDefinition Width="*"/>
                  </Grid.ColumnDefinitions>
                  <ScrollBar Grid.Column="1"
                             Name="PART_HorizontalScrollBar"
                             Orientation="Horizontal"
                             Maximum="{TemplateBinding ScrollableWidth}"
                             ViewportSize="{TemplateBinding ViewportWidth}"
                             Value="{Binding Path=HorizontalOffset, RelativeSource={RelativeSource TemplatedParent}, Mode=OneWay}"
                             Visibility="{TemplateBinding ComputedHorizontalScrollBarVisibility}"/>

                </Grid-->
                                    <!-- Make the scrollbar to start from left edge -->
                                    <ScrollBar Grid.Column="0" Grid.Row="2" Grid.ColumnSpan="2"
                                            Name="PART_HorizontalScrollBar"
                                            Orientation="Horizontal"
                                            Maximum="{TemplateBinding ScrollableWidth}"
                                            ViewportSize="{TemplateBinding ViewportWidth}"
                                            Value="{Binding Path=HorizontalOffset, RelativeSource={RelativeSource TemplatedParent}, Mode=OneWay}"
                                            Visibility="{TemplateBinding ComputedHorizontalScrollBarVisibility}"/>
                                </Grid>
                            </ControlTemplate>
                        </ScrollViewer.Template>
                        <ItemsPresenter SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
                    </ScrollViewer>
                </Border>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
    <Style.Triggers>
        <Trigger Property="IsGrouping" Value="true">
            <Setter Property="ScrollViewer.CanContentScroll" Value="false"/>
        </Trigger>
    </Style.Triggers>
</Style>

这是我的Themes/Generic.xaml:

This is my Themes/Generic.xaml:

<ResourceDictionary.MergedDictionaries>
    <ResourceDictionary Source="/Themes/DataGridEx.xaml"/>
    <ResourceDictionary Source="/Themes/GridComboBox.xaml"/>
</ResourceDictionary.MergedDictionaries>

这是我的App.xaml:

This is my App.xaml:

    <Application x:Class="MyApp.App"
                 xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                 xmlns:local="clr-namespace:MyApp.Common"
                 DispatcherUnhandledException="Application_DispatcherUnhandledException">
                 <!--StartupUri="MainWindow.xaml"-->
        <Application.Resources>
            <ResourceDictionary x:Key="rd">
                <ResourceDictionary.MergedDictionaries>
                    <ResourceDictionary Source="Themes/Generic.xaml"/>
                </ResourceDictionary.MergedDictionaries>
            </ResourceDictionary>
....
        </Application.Resources>
    </Application>

使用此代码，我得到了运行时XamlParseException:无法从文本'local:DataGridEx'创建'类型'".但是，如果我注释掉App.xaml中的MergedDictionaries，它不会抱怨，但是样式也不会生效.

With this code, I got a run-time XamlParseException: "Failed to create a 'Type' from the text 'local:DataGridEx'". However, if I comment out the MergedDictionaries in App.xaml, it doesn't complain, but the style doesn't take effect either.

另一个有趣的事情是，在这个generic.xaml中，我有两个字典.如果我从App.xaml中删除ResourceDictionary，则GridComboBox.xaml可以正常工作，但DataGridEx.xaml则不能.

Another interesting thing is that, in this generic.xaml I have two dictionaries. If I remove the ResourceDictionary from App.xaml, GridComboBox.xaml is working fine, but DataGridEx.xaml is not.

推荐答案

您需要像这样将其合并到App.xaml中:

You need to merge it into App.xaml like this:

<Application.Resources>
    <ResourceDictionary>
        <ResourceDictionary.MergedDictionaries>
            <ResourceDictionary Source="Generic.xaml"/>
        </ResourceDictionary.MergedDictionaries>
    </ResourceDictionary>
</Application.Resources>

如果您已经这样做了，则需要发布代码以提供更多信息.

If you are already doing that, you need to post your code to give more info.

尝试按照此处的说明进行操作.特别是有关将词典设置为Resource并使用Source中完整路径的部分.

Try following the instructions here. Particularly, the parts about having to set your dictionaries to Resource and using the full path in Source.

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