blocks|key|1257560|text|只是默认的ItemsPanel不是VirtualizingStackPanel。您需要更改它：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1257561|<ItemsControl>
++++<ItemsControl.ItemsPanel>
++++++++<ItemsPanelTemplate>
++++++++++++<VirtualizingStackPanel+/>
++++++++</ItemsPanelTemplate>
++++</ItemsControl.ItemsPanel>
</ItemsControl>|code-block|syntax|javascript|1257562|entityMap^0|5|A|H|M|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

It is just that the default <code>ItemsPanel</code> isn't a <code>VirtualizingStackPanel</code>. You need to change it:

<pre><code>&lt;ItemsControl&gt;
 &lt;ItemsControl.ItemsPanel&gt;
 &lt;ItemsPanelTemplate&gt;
 &lt;VirtualizingStackPanel /&gt;
 &lt;/ItemsPanelTemplate&gt;
 &lt;/ItemsControl.ItemsPanel&gt;
&lt;/ItemsControl&gt;
</code></pre>

blocks|key|1257615|text|实际上，除了让ItemsPanelTemplate使用VirtualizingStackPanel之外，还有很多事情要做。ItemsControl的默认ControlTemplate没有ScrollViewer，这是虚拟化的关键。添加到ItemsControl的默认控件模板(使用ListBox的控件模板作为模板)将为我们提供以下内容：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1257616|<ItemsControl+ItemsSource="{Binding+AccountViews.Tables[0]}">
++<ItemsControl.ItemTemplate>
++++<DataTemplate>
++++++<TextBlock+Initialized="TextBlock_Initialized"
+++++++++++++++++Text="{Binding+Name}"+/>
++++</DataTemplate>
++</ItemsControl.ItemTemplate>

++<ItemsControl.ItemsPanel>
++++<ItemsPanelTemplate>
++++++<VirtualizingStackPanel+IsVirtualizing="True"
++++++++++++++++++++++++++++++VirtualizationMode="Recycling"+/>
++++</ItemsPanelTemplate>
++</ItemsControl.ItemsPanel>

++<ItemsControl.Template>
++++<ControlTemplate+TargetType="ItemsControl">
++++++<Border+BorderThickness="{TemplateBinding+BorderThickness}"
++++++++++++++BorderBrush="{TemplateBinding+BorderBrush}"
++++++++++++++Background="{TemplateBinding+Background}">
++++++++<ScrollViewer+CanContentScroll="True"+
++++++++++++++++++++++Padding="{TemplateBinding+Padding}"
++++++++++++++++++++++Focusable="False">
++++++++++<ItemsPresenter+/>
++++++++</ScrollViewer>
++++++</Border>
++++</ControlTemplate>
++</ItemsControl.Template>
</ItemsControl>|code-block|syntax|javascript|1257617|(顺便说一句，查看默认控件模板的一个很好的工具是Show+Me+The+Template)|1257618|注意事项：|1257619|您必须设置ScrollViewer.CanContentScroll="True"，请参阅here了解原因。|1257620|另请注意，我将VirtualizingStackPanel.VirtualizationMode="Recycling"。无论屏幕上显示多少个TextBlocks，这都将减少调用TextBlock_Initialized的次数。你可以阅读更多关于UI虚拟化here+的内容。|1257621|编辑:忘记陈述显而易见的事实:作为替代解决方案，您可以将ItemsControl替换为ListBox+:)另外，查看此Optimizing+Performance+on+MSDN+page，并注意到ItemsControl不在“实现性能特性的控件”表中，这就是我们需要编辑控件模板的原因。|1257622|entityMap|0|LINK|mutability|MUTABLE|url|https://sellsbrothers.com/2091|1|https://stackoverflow.com/questions/1924089/listbox-virtualizingstackpanel-and-smooth-scrolling-in-wpf|2|https://web.archive.org/web/20150708100804/http://www.zagstudio.com:80/blog/497|3|https://msdn.microsoft.com/en-us/library/vstudio/cc716879(v=vs.100).aspx^0|7|I|R|M|1P|C|24|F|2L|C|3A|C|3W|7|0|0|O|K|0|0|0|5|10|19|4|1|0|7|1H|2H|L|3K|5|2|0|S|C|17|7|2R|C|1N|Z|3|0^^$0|@$1|2|3|4|5|6|7|18|8|@$9|19|A|1A|B|C]|$9|1B|A|1C|B|C]|$9|1D|A|1E|B|C]|$9|1F|A|1G|B|C]|$9|1H|A|1I|B|C]|$9|1J|A|1K|B|C]|$9|1L|A|1M|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|1N|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|1O|8|@]|D|@$9|1P|A|1Q|1|1R]]|E|$]]|$1|M|3|N|5|6|7|1S|8|@]|D|@]|E|$]]|$1|O|3|P|5|6|7|1T|8|@$9|1U|A|1V|B|C]]|D|@$9|1W|A|1X|1|1Y]]|E|$]]|$1|Q|3|R|5|6|7|1Z|8|@$9|20|A|21|B|C]|$9|22|A|23|B|C]]|D|@$9|24|A|25|1|26]]|E|$]]|$1|S|3|T|5|6|7|27|8|@$9|28|A|29|B|C]|$9|2A|A|2B|B|C]|$9|2C|A|2D|B|C]]|D|@$9|2E|A|2F|1|2G]]|E|$]]|$1|U|3|-4|5|6|7|2H|8|@]|D|@]|E|$]]]|V|$W|$5|X|Y|Z|E|$10|11]]|12|$5|X|Y|Z|E|$10|13]]|14|$5|X|Y|Z|E|$10|15]]|16|$5|X|Y|Z|E|$10|17]]]]

There's actually much more to it than just making the <code>ItemsPanelTemplate</code> use <code>VirtualizingStackPanel</code>. The default <code>ControlTemplate</code> for <code>ItemsControl</code> does not have a <code>ScrollViewer</code>, which is the key to virtualization. Adding to the the default control template for <code>ItemsControl</code> (using the control template for <code>ListBox</code> as a template) gives us the following:
<pre><code>&lt;ItemsControl ItemsSource=&quot;{Binding AccountViews.Tables[0]}&quot;&gt;
 &lt;ItemsControl.ItemTemplate&gt;
 &lt;DataTemplate&gt;
 &lt;TextBlock Initialized=&quot;TextBlock_Initialized&quot;
 Text=&quot;{Binding Name}&quot; /&gt;
 &lt;/DataTemplate&gt;
 &lt;/ItemsControl.ItemTemplate&gt;

 &lt;ItemsControl.ItemsPanel&gt;
 &lt;ItemsPanelTemplate&gt;
 &lt;VirtualizingStackPanel IsVirtualizing=&quot;True&quot;
 VirtualizationMode=&quot;Recycling&quot; /&gt;
 &lt;/ItemsPanelTemplate&gt;
 &lt;/ItemsControl.ItemsPanel&gt;

 &lt;ItemsControl.Template&gt;
 &lt;ControlTemplate TargetType=&quot;ItemsControl&quot;&gt;
 &lt;Border BorderThickness=&quot;{TemplateBinding BorderThickness}&quot;
 BorderBrush=&quot;{TemplateBinding BorderBrush}&quot;
 Background=&quot;{TemplateBinding Background}&quot;&gt;
 &lt;ScrollViewer CanContentScroll=&quot;True&quot; 
 Padding=&quot;{TemplateBinding Padding}&quot;
 Focusable=&quot;False&quot;&gt;
 &lt;ItemsPresenter /&gt;
 &lt;/ScrollViewer&gt;
 &lt;/Border&gt;
 &lt;/ControlTemplate&gt;
 &lt;/ItemsControl.Template&gt;
&lt;/ItemsControl&gt;
</code></pre>
(BTW, a great tool for looking at default control templates is <a href="https://sellsbrothers.com/2091" rel="noreferrer">Show Me The Template</a>)
Things to notice:
You have to set <code>ScrollViewer.CanContentScroll=&quot;True&quot;</code>, see <a href="https://stackoverflow.com/questions/1924089/listbox-virtualizingstackpanel-and-smooth-scrolling-in-wpf">here</a> for why.
Also notice that I put <code>VirtualizingStackPanel.VirtualizationMode=&quot;Recycling&quot;</code>. This will reduce the numbers of times <code>TextBlock_Initialized</code> is called to however many TextBlocks are visible on the screen. You can read more on UI virtualization <a href="https://web.archive.org/web/20150708100804/http://www.zagstudio.com:80/blog/497" rel="noreferrer">here
</a>.
EDIT: Forgot to state the obvious: as an alternate solution, you can just replace <code>ItemsControl</code> with <code>ListBox</code> :)
Also, check out this <a href="https://msdn.microsoft.com/en-us/library/vstudio/cc716879(v=vs.100).aspx" rel="noreferrer">Optimizing Performance on MSDN page</a> and notice that <code>ItemsControl</code> isn't in the &quot;Controls That Implement Performance Features&quot; table, which is why we need to edit the control template.

blocks|key|1042668|text|基于DavidN的回答，这里有一种你可以在ItemsControl上使用的风格来虚拟化它：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1042669|
<Style+x:Key="ItemsControlVirtualizedStyle"+TargetType="ItemsControl">
++++<Setter+Property="VirtualizingStackPanel.IsVirtualizing"+Value="True"/>
++++<Setter+Property="ScrollViewer.CanContentScroll"+Value="True"/>
++++<Setter+Property="ItemsPanel">
++++++++<Setter.Value>
++++++++++++<ItemsPanelTemplate>
++++++++++++++++<VirtualizingStackPanel+/>
++++++++++++</ItemsPanelTemplate>
++++++++</Setter.Value>
++++</Setter>
++++<Setter+Property="Template">
++++++++<Setter.Value>
++++++++++++<ControlTemplate+TargetType="ItemsControl">
++++++++++++++++<Border
++++++++++++++++++++BorderThickness="{TemplateBinding+Border.BorderThickness}"
++++++++++++++++++++Padding="{TemplateBinding+Control.Padding}"
++++++++++++++++++++BorderBrush="{TemplateBinding+Border.BorderBrush}"
++++++++++++++++++++Background="{TemplateBinding+Panel.Background}"
++++++++++++++++++++SnapsToDevicePixels="True"
++++++++++++++++>
++++++++++++++++++++<ScrollViewer+Padding="{TemplateBinding+Control.Padding}"+Focusable="False">
++++++++++++++++++++++++<ItemsPresenter+SnapsToDevicePixels="{TemplateBinding+UIElement.SnapsToDevicePixels}"+/>
++++++++++++++++++++</ScrollViewer>
++++++++++++++++</Border>
++++++++++++</ControlTemplate>
++++++++</Setter.Value>
++++</Setter>
</Style>|code-block|syntax|javascript|1042670|我不喜欢使用ListBox的建议，因为它们允许在您不一定需要的地方选择行。|1042671|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Building on DavidN's answer, here is a style you can use on an ItemsControl to virtualise it:

<pre><code>&lt;!--Virtualised ItemsControl--&gt;
&lt;Style x:Key="ItemsControlVirtualizedStyle" TargetType="ItemsControl"&gt;
 &lt;Setter Property="VirtualizingStackPanel.IsVirtualizing" Value="True"/&gt;
 &lt;Setter Property="ScrollViewer.CanContentScroll" Value="True"/&gt;
 &lt;Setter Property="ItemsPanel"&gt;
 &lt;Setter.Value&gt;
 &lt;ItemsPanelTemplate&gt;
 &lt;VirtualizingStackPanel /&gt;
 &lt;/ItemsPanelTemplate&gt;
 &lt;/Setter.Value&gt;
 &lt;/Setter&gt;
 &lt;Setter Property="Template"&gt;
 &lt;Setter.Value&gt;
 &lt;ControlTemplate TargetType="ItemsControl"&gt;
 &lt;Border
 BorderThickness="{TemplateBinding Border.BorderThickness}"
 Padding="{TemplateBinding Control.Padding}"
 BorderBrush="{TemplateBinding Border.BorderBrush}"
 Background="{TemplateBinding Panel.Background}"
 SnapsToDevicePixels="True"
 &gt;
 &lt;ScrollViewer Padding="{TemplateBinding Control.Padding}" Focusable="False"&gt;
 &lt;ItemsPresenter SnapsToDevicePixels="{TemplateBinding UIElement.SnapsToDevicePixels}" /&gt;
 &lt;/ScrollViewer&gt;
 &lt;/Border&gt;
 &lt;/ControlTemplate&gt;
 &lt;/Setter.Value&gt;
 &lt;/Setter&gt;
&lt;/Style&gt;
</code></pre>

I do not like the suggestion to use a ListBox as they allow the selection of rows where you do not necessarily want it.

I have an <code>ItemsControl</code> containing a list of data that I would like to virtualize, however <code>VirtualizingStackPanel.IsVirtualizing="True"</code> does not seem to work with an <code>ItemsControl</code>.

Is this really the case or is there another way of doing this that I am not aware of?

To test I have been using the following block of code:

<pre><code>&lt;ItemsControl ItemsSource="{Binding Path=AccountViews.Tables[0]}"
 VirtualizingStackPanel.IsVirtualizing="True"&gt;
&lt;ItemsControl.ItemTemplate&gt;
 &lt;DataTemplate&gt;
 &lt;TextBlock Initialized="TextBlock_Initialized" 
 Margin="5,50,5,50" Text="{Binding Path=Name}" /&gt;
 &lt;/DataTemplate&gt;
&lt;/ItemsControl.ItemTemplate&gt;
&lt;/ItemsControl&gt;
</code></pre>

If I change the <code>ItemsControl</code> to a <code>ListBox</code>, I can see that the <code>Initialized</code> event only runs a handful of times (the huge margins are just so I only have to go through a few records), however as an <code>ItemsControl</code> every item gets initialized. 

I have tried setting the <code>ItemsControlPanelTemplate</code> to a <code>VirtualizingStackPanel</code> but that doesn't seem to help.

Virtualizing an ItemsControl?

虚拟化

我有一个包含要虚拟化的数据列表的ItemsControl，但是VirtualizingStackPanel.IsVirtualizing="True"似乎不能与ItemsControl一起工作。这是真的吗?还是有其他我不知道的方法？为了测试，我使用了以下代码块：<ItemsControl ItemsSource="{B...

问虚拟化ItemsControl？
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