如何在ItemsControl中访问ScrollViewer

Question

我正在尝试在下面的XAML中访问名为“ScrollViewerItems”的ScrollViewer，并在后面的代码中使用它。该名称似乎未被识别，可能是因为它嵌入了ItemsControl中。我不需要命名访问，但是如何在代码后面找到ItemsControl的ScrollViewer？

<ItemsControl x:Name="EnteredItemsView" ItemsSource="{Binding LineItems}"  VirtualizingStackPanel.IsVirtualizing="True" ScrollViewer.CanContentScroll="True" ScrollViewer.HorizontalScrollBarVisibility="Disabled" ScrollViewer.VerticalScrollBarVisibility="Auto">
    <ItemsControl.ItemsPanel>
        <ItemsPanelTemplate>
            <VirtualizingStackPanel />
        </ItemsPanelTemplate>
    </ItemsControl.ItemsPanel>
    <ItemsControl.Template>
        <ControlTemplate>
            <ScrollViewer x:Name="ScrollViewerItems" Focusable="False">
                <ItemsPresenter SnapsToDevicePixels="{TemplateBinding UIElement.SnapsToDevicePixels}" />
            </ScrollViewer>
        </ControlTemplate>
    </ItemsControl.Template>
    <ItemsControl.ItemTemplate>
    ...

Answer 1

ScrollViewer是ItemsControl的可视子级：

var scrollViewer =
    VisualTreeHelper.GetChild(EnteredItemsView, 0) as ScrollViewer;

---

请注意，必须先加载ItemsControl，然后才能访问该子项。

您可以向ItemsControl

添加Loaded处理程序

<ItemsControl Loaded="ItemsControlLoaded" ...>

您访问ScrollViewer的地方

private void ItemsControlLoaded(object sender, EventArgs e)
{
    var itemsControl = sender as DependencyObject;
    var scrollViewer =
        VisualTreeHelper.GetChild(itemsControl, 0) as ScrollViewer;
}