WPF DataGrid 和 ScrollViewer 性能缓慢

2024-02-27

我有这样的数据网格样式:

<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>

                                <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}"
                                        Grid.Row="0" />

                        <Canvas Width="128"
                                VerticalAlignment="Stretch"
                                HorizontalAlignment="Left"
                                Grid.Row="0"
                                x:Name="Image" />
                    </Grid>
                </ScrollViewer>
            </Border>
        </ControlTemplate>
    </Setter.Value>
</Setter>

我知道如果在数据网格上加载大量数据,性能就会受到影响。我可以使用虚拟化来减轻性能影响,但是,一旦我将网格放入自定义滚动查看器中,虚拟化就会丢失。

我正在尝试将其恢复,但我不确定如何 - 同时仍然保留名为的元素Image在我的 XAML 中。

基本上,我想让图像与数据网格内容一起滚动,上面的代码工作正常,只是我不知道如何启用虚拟化。有可能吗?

Update:看来我发现了一个问题。最后Grid模板中出现问题:

<Grid>
    <ItemsPresenter SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"
                    Grid.Row="0" />

    <Canvas Width="128"
            VerticalAlignment="Stretch"
            HorizontalAlignment="Left"
            Grid.Row="0"
            x:Name="Image" />
</Grid>

我一拿起Canvas and Grid出来,只留下ItemsPresenter,然后又很快了。我怎样才能快速获得它并仍然保留它Canvas?

更新2:我该如何应用这个(ScrollViewer 使用 DataGrid 时性能缓慢 https://stackoverflow.com/a/7256780/283055)我的策略Grid如上所示?我试过这个:

<Grid>
    <Grid.RowDefinitions>
        <RowDefinition Height="*" />
    </Grid.RowDefinitions>

    <Rectangle Name="sizingElement" Grid.Row="0" Fill="Transparent" Margin="1"/>

    <ItemsPresenter SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"
                    Grid.Row="0"
                    Height="{Binding ElementName=sizingElement, Path=ActualHeight, FallbackValue=1}" />

    <Canvas Width="128"
            VerticalAlignment="Stretch"
            HorizontalAlignment="Left"
            Grid.Row="0"
            x:Name="Image" />
</Grid>

然而,现在滚动条消失了?

我意识到我无法虚拟化Canvas,而且我不需要。事实上,整个Canvas被绘制出来,我没有逻辑将它分成更小的部分。只要我可以保持行虚拟化,渲染整个图像就完全没问题。


我已经为基于 TreeView (.Net 4.0) 的自定义控件工作了虚拟化。我修改了一些样式以匹配 DataGrid,希望它适合您的情况:

  <Style TargetType="{x:Type DataGrid}">
<Setter Property="OverridesDefaultStyle" Value="True" />
<Setter Property="VirtualizingStackPanel.IsVirtualizing" Value="True" />
<Setter Property="VirtualizingStackPanel.VirtualizationMode" Value="Recycling" />
<Setter Property="BorderThickness" Value="1" />
<Setter Property="ItemsPanel">
  <Setter.Value>
    <ItemsPanelTemplate>
      <VirtualizingStackPanel IsItemsHost="True" VirtualizingStackPanel.IsVirtualizing="True"
                              VirtualizingStackPanel.VirtualizationMode="Recycling" />
    </ItemsPanelTemplate>
  </Setter.Value>
</Setter>
<Setter Property="Template">
  <Setter.Value>
            <ControlTemplate TargetType="{x:Type DataGrid}">
      <Border x:Name="Border" Grid.Column="0" Background="{TemplateBinding Background}"
              BorderBrush="{StaticResource SolidBorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" CornerRadius="2">
        <DockPanel>

            <ScrollViewer x:Name="PART_Body_Scroll" Background="White" HorizontalScrollBarVisibility="Auto"
                        VerticalScrollBarVisibility="Auto" CanContentScroll="True">

              <ItemsPresenter x:Name="ItemsHost" VirtualizingStackPanel.IsVirtualizing="True"
                            VirtualizingStackPanel.VirtualizationMode="Recycling" />

          </ScrollViewer>

        </DockPanel>
      </Border>
    </ControlTemplate>
  </Setter.Value>
</Setter>
本文内容由网友自发贡献,版权归原作者所有,本站不承担相应法律责任。如您发现有涉嫌抄袭侵权的内容,请联系:hwhale#tublm.com(使用前将#替换为@)

WPF DataGrid 和 ScrollViewer 性能缓慢 的相关文章

随机推荐