我正在清理 App.xaml 并将一些样式移到 Generic.xaml 中。但是,这些样式没有任何效果。为什么?这是使 App.xaml 整洁的正确做法吗?
编辑(包括一些源代码):
目标是重新设置 WPF DataGrid 的样式以使滚动条从上到下和从左到右运行(默认样式不包括行和列标题)。
当我把它放在 App.xaml 中时,这种风格就起作用了。因为它是一大块代码,我想将它从 App.xaml 移到 /Themes/DataGridEx.xaml 中。顺便说一句,DataGridEx 是我从 WPF DataGrid 派生的扩展类。
这是我的 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>
这是我的主题/Generic.xaml:
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="/Themes/DataGridEx.xaml"/>
<ResourceDictionary Source="/Themes/GridComboBox.xaml"/>
</ResourceDictionary.MergedDictionaries>
这是我的 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 'Type'”。但是,如果我注释掉 App.xaml 中的 MergedDictionaries,它不会抱怨,但样式也不会生效。
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,GridComboBox.xaml 工作正常,但 DataGridEx.xaml 不是。