我有一个 UserControl 使用 Itemscontrol 等绘制数据上下文。我有三个相同用户控件的对象,但具有不同的数据上下文,这些对象在程序启动时被初始化。问题是数据上下文太大了,所以它在每个对象上绘制了大约 2000 个 UI 元素。这需要很多时间,真正让我烦恼的是 WPF 在单个 UIThread 中运行,所以我的计算机使用了总 CPU 功率的 1/8 来绘制它。我怎样才能让它更快?
代码(DynamicShelViewModel 是一个用户控件)
dataContextBestSellers = new DynamicShelfViewModel(_config, dataRepository, ProductSelectionMode.BestSellers);
dataContextNormal = new DynamicShelfViewModel(_config, dataRepository, ProductSelectionMode.Normal);
dataContextFull = new DynamicShelfViewModel(_config, dataRepository, ProductSelectionMode.AllProducts);
ScrollGrid = new Grid();
ScrollGrid.Children.Add(dataContextBestSellers);
ScrollGrid.Children.Add(dataContextNormal);
ScrollGrid.Children.Add(dataContextFull);
这大约需要 2 分钟才能完成。
这是 DynamicShelfViewModel 的 XAML 代码
<Grid>
<ItemsControl x:Name="ShelvesControl" VirtualizingStackPanel.IsVirtualizing="True"
VirtualizingStackPanel.VirtualizationMode="Recycling" DataContext="{Binding}" Width="{Binding Size.Width}"
VerticalAlignment="Top" Height="{Binding Size.Height}" Grid.Column="0" Grid.Row="1"
ItemsSource="{Binding ShelvesInViewPort}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel VerticalAlignment="Stretch " HorizontalAlignment="Stretch" Orientation="Vertical" />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid Name="ShelfGrid" Height="{Binding Height}" MaxHeight="{Binding Height}"
DataContext="{Binding}">
<Grid.Background>
<SolidColorBrush Color="{Binding Color}" />
</Grid.Background>
<Grid.RowDefinitions>
<RowDefinition Height="*" />
<RowDefinition Height="{Binding SplitterSize}" />
</Grid.RowDefinitions>
<TextBlock Name="stretchingLabel" Height="{Binding SplitterSize}" Padding="0" Grid.Row="1"
VerticalAlignment="Stretch" HorizontalAlignment="Stretch">
<TextBlock.Background>
<ImageBrush
ImageSource="{Binding Converter={Utilities1:FancySourceConverter}, ConverterParameter=Images/ShelvesImages/shelfhorisontal.png}" />
</TextBlock.Background>
<Grid VerticalAlignment="Stretch"
Width="{Binding ElementName=stretchingLabel,Path=ActualWidth}"
Height="{Binding ElementName=stretchingLabel,Path=ActualHeight}" HorizontalAlignment="Stretch">
<Grid.RowDefinitions>
<RowDefinition Height="0.24*" />
<RowDefinition Height="0.62*" />
<RowDefinition Height="0.24*" />
</Grid.RowDefinitions>
<my:CategoryLine VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Grid.Row="1"
DataContext="{Binding ElementName=ShelfGrid, Path=DataContext}">
</my:CategoryLine>
</Grid>
</TextBlock>
<TextBlock Name="stretchedLabel" VerticalAlignment="Stretch" HorizontalAlignment="Stretch"
Grid.Row="0" Padding="0">
<ItemsControl ItemsSource="{Binding Products}" VerticalAlignment="Stretch"
HorizontalAlignment="Stretch">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<UniformGrid DataContext="{Binding}"
Width="{Binding ElementName=stretchedLabel, Path=ActualWidth}"
MaxHeight="{Binding ElementName=stretchedLabel, Path=ActualHeight}"
Height="{Binding ElementName=stretchedLabel, Path=ActualHeight}"
Columns="{Binding Path=DataContext.Slots, RelativeSource={RelativeSource AncestorType={x:Type Grid}}}" Rows="1"
VerticalAlignment="Stretch" Name="ParentUniformGrid" HorizontalAlignment="Stretch" />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<ItemsControl>
<Grid Height="{Binding ElementName=stretchedLabel, Path=ActualHeight}"
VerticalAlignment="Stretch" HorizontalAlignment="Stretch">
<Grid.RowDefinitions>
<RowDefinition Height="*" />
<RowDefinition
Height="{Binding ElementName=ParentUniformGrid,Path=DataContext.SplitterSize}" />
</Grid.RowDefinitions>
<Image VerticalAlignment="Bottom" Grid.Row="0"
HorizontalAlignment="Center" x:Name="ProductImage" Source="{Binding Converter={Utilities:ProductImageConverter}}"
Height="{Binding ImageHeight}" MaxHeight="{Binding ImageHeight}" MouseLeftButtonUp="BuyProductUsingImage" />
<Label Padding="0" Margin="0 1 0 0" Grid.Row="1" Background="LightGray"
VerticalAlignment="Stretch" VerticalContentAlignment="Center" HorizontalContentAlignment="Center"
HorizontalAlignment="Stretch">
<Label VerticalAlignment="Center" Margin="1"
HorizontalAlignment="Center" VerticalContentAlignment="Center" HorizontalContentAlignment="Center" Background="#fff"
Padding="0" MaxWidth="{Binding ElementName=ShelvesControl, Path=DataContext.PriceLabelWidthSize}"
Width="{Binding ElementName=ShelvesControl, Path=DataContext.PriceLabelWidthSize}">
<Viewbox VerticalAlignment="Center"
HorizontalAlignment="Center">
<StackPanel Orientation="Horizontal"
VerticalAlignment="Bottom" Margin="1" Background="#fff" HorizontalAlignment="Left">
<Label Background="Yellow" Padding="2 0 2 0"
VerticalContentAlignment="Bottom" FontWeight="Bold" Content="{Binding Price}">
</Label>
</StackPanel>
</Viewbox>
</Label>
</Label>
</Grid>
</ItemsControl>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</TextBlock>
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</Grid>
</UserControl>