[英]How to add content inside DataGrid's ScrollViewer?
我有一個DataGrid:
<DataGrid ...></DataGrid>
在默認模板的某處,有一個ScrollViewer
。 我想在其中添加內容。 目前我這樣做:
<Grid>
<DataGrid Grid.Row="0">...</DataGrid>
<Canvas Width="128" VerticalAlignment="Stretch" HorizontalAlignment="Left" Grid.Row="0" Margin="0,25,0,0">
<Rectangle Width="32" Height="256" Canvas.Top="0" Canvas.Left="0" Stroke="Black" StrokeThickness="2" />
</Canvas>
</Grid>
看起來像這樣:
也就是說,畫布會在網格內繪制。 這一切都很棒,但畫布不會隨數據網格一起滾動。 現在我意識到我可能需要更改控件模板並將畫布放在滾動查看器中:
<DataGrid>
<ControlTemplate>
<ScrollViewer>
<Grid>
<ContentPresenter Grid.Row="0" />
<Canvas Width="128" VerticalAlignment="Stretch" HorizontalAlignment="Left" Grid.Row="0" Margin="0,25,0,0">
<Rectangle Width="32" Height="256" Canvas.Top="0" Canvas.Left="0" Stroke="Black" StrokeThickness="2" />
</Canvas>
</Grid>
</ScrollViewer>
</ControlTemplate>
</DataGrid>
但是,這給了我錯誤:
PresentationFramework.dll中出現“System.InvalidOperationException”類型的第一次機會異常
附加信息:在使用ItemsSource之前,項集合必須為空。
如何將畫布放在滾動條內以使其與內容一起滾動?
DataGrid是ItemsControl,ItemsControl的ContentProperty是Items屬性。 這是反編譯的源代碼,請注意ContentProperty屬性:
[DefaultEvent("OnItemsChanged"), DefaultProperty("Items")]
[ContentProperty("Items")]
[StyleTypedProperty(Property = "ItemContainerStyle", StyleTargetType = typeof(FrameworkElement))]
[Localizability(LocalizationCategory.None, Readability = Readability.Unreadable)] // cannot be read & localized as string
public class ItemsControl : Control, IAddChild, IGeneratorHost
{
這意味着,如果您執行以下操作:
<DataGrid>
<SomethingHere>
</DataGrid>
然后<SomethingHere>
- 這是內容 - 應用於Items
屬性。 如果您隨后綁定到ItemsSource
屬性,您將收到您看到的錯誤 - “在使用ItemsSource之前,Items集合必須為空”。
如果你曾經使用過
<DataGrid>
<DataGrid.Template>
<ControlTemplate> ...
你不會得到錯誤。
在任何情況下,最好使用Blend或VS11提取DataGrid的完整ControlTemplate並修改它,例如
<Style x:Key="{ComponentResourceKey ResourceId=DataGridSelectAllButtonStyle, TypeInTargetAssembly={x:Type DataGrid}}" TargetType="{x:Type Button}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Grid>
<Rectangle x:Name="Border" Fill="{DynamicResource {x:Static SystemColors.ControlBrushKey}}" SnapsToDevicePixels="True"/>
<Polygon x:Name="Arrow" Fill="Black" HorizontalAlignment="Right" Margin="8,8,3,3" Opacity="0.15" Points="0,10 10,10 10,0" Stretch="Uniform" VerticalAlignment="Bottom"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Stroke" TargetName="Border" Value="{DynamicResource {x:Static SystemColors.ControlDarkBrushKey}}"/>
</Trigger>
<Trigger Property="IsPressed" Value="True">
<Setter Property="Fill" TargetName="Border" Value="{DynamicResource {x:Static SystemColors.ControlDarkBrushKey}}"/>
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Visibility" TargetName="Arrow" Value="Collapsed"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="DataGridStyle1" TargetType="{x:Type DataGrid}">
<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="ScrollViewer.PanningMode" Value="Both"/>
<Setter Property="Stylus.IsFlicksEnabled" Value="False"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type DataGrid}">
<Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Padding="{TemplateBinding Padding}" SnapsToDevicePixels="True">
<ScrollViewer x:Name="DG_ScrollViewer" Focusable="false">
<ScrollViewer.Template>
<ControlTemplate TargetType="{x:Type ScrollViewer}">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="*"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<Button Command="{x:Static DataGrid.SelectAllCommand}" Focusable="false" Style="{DynamicResource {ComponentResourceKey ResourceId=DataGridSelectAllButtonStyle, TypeInTargetAssembly={x:Type DataGrid}}}" Visibility="{Binding HeadersVisibility, ConverterParameter={x:Static DataGridHeadersVisibility.All}, Converter={x:Static DataGrid.HeadersVisibilityConverter}, RelativeSource={RelativeSource AncestorType={x:Type DataGrid}}}" Width="{Binding CellsPanelHorizontalOffset, RelativeSource={RelativeSource AncestorType={x:Type DataGrid}}}"/>
<DataGridColumnHeadersPresenter x:Name="PART_ColumnHeadersPresenter" Grid.Column="1" Visibility="{Binding HeadersVisibility, ConverterParameter={x:Static DataGridHeadersVisibility.Column}, Converter={x:Static DataGrid.HeadersVisibilityConverter}, RelativeSource={RelativeSource AncestorType={x:Type DataGrid}}}"/>
<ScrollContentPresenter x:Name="PART_ScrollContentPresenter" CanContentScroll="{TemplateBinding CanContentScroll}" Grid.ColumnSpan="2" Grid.Row="1"/>
<ScrollBar x:Name="PART_VerticalScrollBar" Grid.Column="2" Maximum="{TemplateBinding ScrollableHeight}" Orientation="Vertical" Grid.Row="1" Visibility="{TemplateBinding ComputedVerticalScrollBarVisibility}" Value="{Binding VerticalOffset, Mode=OneWay, RelativeSource={RelativeSource TemplatedParent}}" ViewportSize="{TemplateBinding ViewportHeight}"/>
<Grid Grid.Column="1" Grid.Row="2">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="{Binding NonFrozenColumnsViewportHorizontalOffset, RelativeSource={RelativeSource AncestorType={x:Type DataGrid}}}"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<ScrollBar x:Name="PART_HorizontalScrollBar" Grid.Column="1" Maximum="{TemplateBinding ScrollableWidth}" Orientation="Horizontal" Visibility="{TemplateBinding ComputedHorizontalScrollBarVisibility}" Value="{Binding HorizontalOffset, Mode=OneWay, RelativeSource={RelativeSource TemplatedParent}}" ViewportSize="{TemplateBinding ViewportWidth}"/>
</Grid>
</Grid>
</ControlTemplate>
</ScrollViewer.Template>
<Grid>
<ItemsPresenter SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
<!-- your canvas here -->
<Canvas Width="128" VerticalAlignment="Stretch" HorizontalAlignment="Left" Grid.Row="0" Margin="0,25,0,0">
<Rectangle Width="32" Height="256" Canvas.Top="0" Canvas.Left="0" Stroke="Black" StrokeThickness="2" />
</Canvas>
</Grid>
</ScrollViewer>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsGrouping" Value="true">
<Setter Property="ScrollViewer.CanContentScroll" Value="false"/>
</Trigger>
</Style.Triggers>
</Style>
</Window.Resources>
<Grid>
<DataGrid HorizontalAlignment="Left" Margin="125,110,0,0" VerticalAlignment="Top" Height="134" Width="258" Style="{DynamicResource DataGridStyle1}"/>
</Grid>
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.