C# WPF 列表框不随 ItemsSource 更新
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/1003838/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
WPF ListBox not updating with the ItemsSource
提问by Paul Prewett
I have what I believe should be simple two-way databinding in WPF setup, but the listbox (target) is not updating as the collection changes.
我认为在 WPF 设置中应该是简单的双向数据绑定，但是列表框（目标）不会随着集合的变化而更新。
I'm setting this ItemsSource of the ListBox programmatically:
我正在以编程方式设置 ListBox 的这个 ItemsSource：
lstVariable_Selected.ItemsSource = m_VariableList;
And the ListBox is declared as follows:
ListBox 声明如下：
<ListBox Margin="5" Name="lstVariable_Selected">
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<VirtualizingStackPanel Orientation="Horizontal"/>
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
<ListBox.ItemTemplate>
<DataTemplate>
<Border BorderBrush="Gray" BorderThickness="1" Margin="0">
<TextBlock FontSize="25" Text="{Binding Path=Name}" />
</Border>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
When I initially set the ItemsSource, the ListBox (which is not visible at the time) gets its items set. However, if I go view the ListBox, updates seem to stop at that point.
当我最初设置 ItemsSource 时，ListBox（当时不可见）会设置其项目。但是，如果我查看 ListBox，更新似乎会在那时停止。
I can then remove an item from the m_VariableList collection, and it does not disappear from the ListBox. Likewise, if I add one, it doesn't appear.
然后我可以从 m_VariableList 集合中删除一个项目，并且它不会从 ListBox 中消失。同样，如果我添加一个，它也不会出现。
What gives?
是什么赋予了？
采纳答案by rmoore
Is your m_VariableList implementing INotifyCollectionChanged? If it's not an ObservableCollection, then changes to it's contents will not automatically be reflected in the UI.
您的 m_VariableList 是否实现了INotifyCollectionChanged？如果它不是 ObservableCollection，则对其内容的更改不会自动反映在 UI 中。
回答by Tony Borres
The problem is not in the XAML that you have provided. I used the same XAML successfully in a test application; however, I was able to replicate the issue you are experiencing by re-instantiating the m_VariableList variable.
问题不在您提供的 XAML 中。我在测试应用程序中成功使用了相同的 XAML；但是，我能够通过重新实例化 m_VariableList 变量来重现您遇到的问题。
When the m_VariableList is given a new instance, or pointed to a new object, it is not reflected in the ListBox because the control has its own reference to the data. This may not be the cause of your problem, but I'd recommend looking over your code-behind to ensure that the variable is not getting re-instantiated.
当 m_VariableList 被赋予一个新实例，或指向一个新对象时，它不会反映在 ListBox 中，因为控件有自己的数据引用。这可能不是您的问题的原因，但我建议您查看您的代码隐藏以确保该变量不会被重新实例化。
回答by Matus Babinsky
i got stuck for more than hour and then simple logic solved this problem just set itemsource to clear list and then set source u need again
我卡住了一个多小时，然后简单的逻辑解决了这个问题，只需将 itemsource 设置为清除列表，然后再次设置您需要的源
lstVariable_Selected.ItemsSource = new List<Object>();
lstVariable_Selected.ItemsSource = m_VariableList;
