Question

我有一个非常慢的ItemsControl，其中包含最多5个DataGrids。（显示彼此相邻）每当我更新此控件时，我的整个UI都会落后（~10秒）。每个Datagrid有大约50-100个项目，有4个预定义列（不自动生成）。网格的项目源同时更新。

这是我的XAML：

        <ScrollViewer Grid.Row="1" ScrollViewer.VerticalScrollBarVisibility="Auto" ScrollViewer.HorizontalScrollBarVisibility="Auto">
        <ItemsControl x:Name="icjudges"  ItemsSource="{Binding Judges}" VirtualizingPanel.IsVirtualizing="True" VirtualizingPanel.VirtualizationMode="Recycling">
            <ItemsControl.ItemsPanel>
                <ItemsPanelTemplate>
                    <WrapPanel />
                </ItemsPanelTemplate>
            </ItemsControl.ItemsPanel>
            <ItemsControl.ItemTemplate>
                <DataTemplate>
                    <Grid>
                        <Grid.RowDefinitions>
                            <RowDefinition Height="auto" />
                            <RowDefinition Height="*" />
                        </Grid.RowDefinitions>
                        <StackPanel Orientation="Horizontal" Grid.Row="0">
                            <TextBlock Text="{Binding Fullname}" Margin="4" />
                        </StackPanel>
                        <DataGrid Grid.Row="1" Margin="4,0" ScrollViewer.CanContentScroll="False" ItemsSource="{Binding}" SelectionUnit="FullRow" VirtualizingPanel.IsVirtualizing="True" VirtualizingPanel.VirtualizationMode="Recycling" AutoGenerateColumns="False" SelectedIndex="0" AlternationCount="2" SelectionMode="Single" CanUserAddRows="False" CanUserDeleteRows="False" IsReadOnly="True">
                            <DataGrid.DataContext>
                                <CollectionViewSource>
                                    <CollectionViewSource.Source>
                                        <MultiBinding Converter="{StaticResource selectedtrickrankingconv}">
                                            <Binding Path="TrickRankings" />
                                            <Binding Path="DataContext.CurrentRunEntry.SelectedTrick" RelativeSource="{RelativeSource FindAncestor, AncestorType={x:Type UserControl}}" />
                                        </MultiBinding>
                                    </CollectionViewSource.Source>
                                </CollectionViewSource>
                            </DataGrid.DataContext>
                            <DataGrid.Columns>
                                <DataGridTextColumn Header="Rank" Binding="{Binding Rank}" HeaderStyle="{StaticResource centerheaderstyle}" MinWidth="20" CellStyle="{StaticResource centercellstyle}" />
                                <DataGridTextColumn Header="Name" Binding="{Binding Trick.Entry.Athlete.NameShort}" HeaderStyle="{StaticResource leftheaderstyle}"   MinWidth="100" />
                                <DataGridTextColumn Header="Run" Binding="{Binding Trick.Entry.Run.Number}"  HeaderStyle="{StaticResource centerheaderstyle}"  MinWidth="20" CellStyle="{StaticResource centercellstyle}" />
                                <DataGridTextColumn Header="Score" Binding="{Binding ValueFormatted}"  HeaderStyle="{StaticResource rightheaderstyle}"   MinWidth="30" CellStyle="{StaticResource rightcellstyle}" />
                            </DataGrid.Columns>
                        </DataGrid>
                    </Grid>
                </DataTemplate>
            </ItemsControl.ItemTemplate>
        </ItemsControl>
    </ScrollViewer>

任何想法如何加快渲染过程？当我更新datagrids时，我的UI保持响应对我来说非常重要。我也尝试用ListViews替换Datagrids，但它几乎和以前一样慢。

我想我发现了这个问题，这里是提供数据的转换器：

    public class SelectedTrickJudgeScoreRankingsConverter : IMultiValueConverter
{
    public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
    {
        if (values.Count() != 2)
            return null;
        if (values.Any(x => x == DependencyProperty.UnsetValue || x == null))
            return null;

        IEnumerable<JudgeRanking> Rankings = (IEnumerable<JudgeRanking>) values[0];
        Trick CurrentTrick = (Trick)values[1];

        return Rankings.FirstOrDefault(t => t.Trick.Number == CurrentTrick.Number).ScoresSorted;
    }

    public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

    public IEnumerable<Score> ScoresSorted
    {
        get { return Scores.Where(s => s.IsValid).OrderBy(s => s.Rank); }
    }

public bool IsValid
    {
        get
        {
            if (Value == null)
                return false;
            if (Value.Value >= (decimal)Trick.Entry.ContestPart.MinScore && Value.Value <= (decimal)Trick.Entry.ContestPart.MaxScore)
                return true;
            return false;
        }
    }

如果我返回ScoresSorted它非常慢，如果我只返回得分（未排序）它的速度更快，但我不知道要改变什么，因为我需要它排序

我编写了一个小型测试应用程序来演示UI的滞后，您可以在这里下载。 https://1drv.ms/u/s!AreXFr2kgVXYjacFH0-MZsnOARPLEA

KR Manu

Answer 1

我也被这种行为困住了。但我找到了一个解决办法，将DataGrids替换为ListBox，并将ItemsPanel重新定义为：

<ListBox.ItemsPanel>
    <ItemsPanelTemplate>
          <UniformGrid Columns="1"/>
   </ItemsPanelTemplate>
</ListBox.ItemsPanel>

之前，只需创建一个包含所需列数的网格（以模拟标题）。

它适用于我。

ItemsControl中的慢数据网格

1 个答案: