我正在尝试创建与Windows 8 SDK示例中的ScrollViewerSample类似的体验，以便能够在向左和向右滚动时捕捉到ScrollViewer内的项目。样本（有效）的实现是这样的：
<ScrollViewer x:Name="scrollViewer" Width="480" Height="270"
HorizontalAlignment="Left" VerticalAlignment="Top"
VerticalScrollBarVisibility="Disabled" HorizontalScrollBarVisibility="Auto"
ZoomMode="Disabled" HorizontalSnapPointsType="Mandatory">
<StackPanel Orientation="Horizontal">
<Image Width="480" Height="270" AutomationProperties.Name="Image of a cliff" Source="images/cliff.jpg" Stretch="None" HorizontalAlignment="Left" VerticalAlignment="Top"/>
<Image Width="480" Height="270" AutomationProperties.Name="Image of Grapes" Source="images/grapes.jpg" Stretch="None" HorizontalAlignment="Left" VerticalAlignment="Top"/>
<Image Width="480" Height="270" AutomationProperties.Name="Image of Mount Rainier" Source="images/Rainier.jpg" Stretch="None" HorizontalAlignment="Left" VerticalAlignment="Top"/>
<Image Width="480" Height="270" AutomationProperties.Name="Image of a sunset" Source="images/sunset.jpg" Stretch="None" HorizontalAlignment="Left" VerticalAlignment="Top"/>
<Image Width="480" Height="270" AutomationProperties.Name="Image of a valley" Source="images/valley.jpg" Stretch="None" HorizontalAlignment="Left" VerticalAlignment="Top"/>
</StackPanel>
</ScrollViewer>
与我期望的实现的唯一区别在于我不希望StackPanel内部有项目，但我可以绑定它。我试图用ItemsControl完成这个，但由于某种原因，Snap行为没有启动：
<ScrollViewer x:Name="scrollViewer" Width="480" Height="270"
HorizontalAlignment="Left" VerticalAlignment="Top"
VerticalScrollBarVisibility="Disabled" HorizontalScrollBarVisibility="Auto"
ZoomMode="Disabled" HorizontalSnapPointsType="Mandatory">
<ItemsControl>
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<Image Width="480" Height="270" AutomationProperties.Name="Image of a cliff" Source="images/cliff.jpg" Stretch="None" HorizontalAlignment="Left" VerticalAlignment="Top"/>
<Image Width="480" Height="270" AutomationProperties.Name="Image of Grapes" Source="images/grapes.jpg" Stretch="None" HorizontalAlignment="Left" VerticalAlignment="Top"/>
<Image Width="480" Height="270" AutomationProperties.Name="Image of Mount Rainier" Source="images/Rainier.jpg" Stretch="None" HorizontalAlignment="Left" VerticalAlignment="Top"/>
<Image Width="480" Height="270" AutomationProperties.Name="Image of a sunset" Source="images/sunset.jpg" Stretch="None" HorizontalAlignment="Left" VerticalAlignment="Top"/>
<Image Width="480" Height="270" AutomationProperties.Name="Image of a valley" Source="images/valley.jpg" Stretch="None" HorizontalAlignment="Left" VerticalAlignment="Top"/>
</ItemsControl>
</ScrollViewer>
建议将不胜感激！
感谢Denis，我最终在ItemsControl上使用了以下Style，并完全删除了ScrollViewer和内联ItemsPanelTemplate：
<Style x:Key="ItemsControlStyle" TargetType="ItemsControl">
<Setter Property="ItemsPanel">
<Setter.Value>
<ItemsPanelTemplate>
<VirtualizingStackPanel Orientation="Horizontal"/>
</ItemsPanelTemplate>
</Setter.Value>
</Setter>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ItemsControl">
<ScrollViewer Style="{StaticResource HorizontalScrollViewerStyle}" HorizontalSnapPointsType="Mandatory">
<ItemsPresenter />
</ScrollViewer>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
答案 0 :(得分：12)
获取快照点以使用绑定集合可能会非常棘手。对于快照点工作，ScrollViewer的直接子项应该实现IScrollSnapPointsInfo接口。 ItemsControl不实现IScrollSnapPointsInfo，因此您不会看到捕捉行为。
要解决此问题，您可以选择以下几种方法：
我已经实施了以前的方法并且可以确认它有效，但在您的情况下，自定义样式可能是更好的选择。
答案 1 :(得分：1)
好的，这是水平ListView的最简单（和独立）示例，带有绑定项目和正确工作的捕捉（请参阅以下代码中的注释）。
<强> XAML ：
<ListView x:Name="YourListView"
ItemsSource="{x:Bind Path=Items}"
Loaded="YourListView_OnLoaded">
<!--Set items panel to horizontal-->
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<ItemsStackPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<!--Some item template-->
<ListView.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding}"/>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
后台代码：
private void YourListView_OnLoaded(object sender, RoutedEventArgs e)
{
//get ListView
var yourList = sender as ListView;
//*** yourList style-based changes ***
//see Style here https://msdn.microsoft.com/en-us/library/windows/apps/mt299137.aspx
//** Change orientation of scrollviewer (name in the Style "ScrollViewer") **
//1. get scrollviewer (child element of yourList)
var sv = GetFirstChildDependencyObjectOfType<ScrollViewer>(yourList);
//2. enable ScrollViewer horizontal scrolling
sv.HorizontalScrollMode =ScrollMode.Auto;
sv.HorizontalScrollBarVisibility = ScrollBarVisibility.Auto;
sv.IsHorizontalRailEnabled = true;
//3. disable ScrollViewer vertical scrolling
sv.VerticalScrollMode = ScrollMode.Disabled;
sv.VerticalScrollBarVisibility = ScrollBarVisibility.Disabled;
sv.IsVerticalRailEnabled = false;
// //no we have horizontally scrolling ListView
//** Enable snapping **
sv.HorizontalSnapPointsType = SnapPointsType.MandatorySingle; //or you can use SnapPointsType.Mandatory
sv.HorizontalSnapPointsAlignment = SnapPointsAlignment.Near; //example works only for Near case, for other there should be some changes
// //no we have horizontally scrolling ListView with snapping and "scroll last item into view" bug (about bug see here http://stackoverflow.com/questions/11084493/snapping-scrollviewer-in-windows-8-metro-in-wide-screens-not-snapping-to-the-las)
//** fix "scroll last item into view" bug **
//1. Get items presenter (child element of yourList)
var ip = GetFirstChildDependencyObjectOfType<ItemsPresenter>(yourList);
// or var ip = GetFirstChildDependencyObjectOfType<ItemsPresenter>(sv); //also will work here
//2. Subscribe to its SizeChanged event
ip.SizeChanged += ip_SizeChanged;
//3. see the continuation in: private void ip_SizeChanged(object sender, SizeChangedEventArgs e)
}
public static T GetFirstChildDependencyObjectOfType<T>(DependencyObject depObj) where T : DependencyObject
{
if (depObj is T) return depObj as T;
for (var i = 0; i < VisualTreeHelper.GetChildrenCount(depObj); i++)
{
var child = VisualTreeHelper.GetChild(depObj, i);
var result = GetFirstChildDependencyObjectOfType<T>(child);
if (result != null) return result;
}
return null;
}
private void ip_SizeChanged(object sender, SizeChangedEventArgs e)
{
//3.0 if rev size is same as new - do nothing
//here should be one more condition added by && but it is a little bit complicated and rare, so it is omitted.
//The condition is: yourList.Items.Last() must be equal to (yourList.Items.Last() used on previous call of ip_SizeChanged)
if (e.PreviousSize.Equals(e.NewSize)) return;
//3.1 get sender as our ItemsPresenter
var ip = sender as ItemsPresenter;
//3.2 get the ItemsPresenter parent to get "viewable" width of ItemsPresenter that is ActualWidth of the Scrollviewer (it is scrollviewer actually, but we need just its ActualWidth so - as FrameworkElement is used)
var sv = ip.Parent as FrameworkElement;
//3.3 get parent ListView to be able to get elements Containers
var yourList = GetParent<ListView>(ip);
//3.4 get last item ActualWidth
var lastItem = yourList.Items.Last();
var lastItemContainerObject = yourList.ContainerFromItem(lastItem);
var lastItemContainer = lastItemContainerObject as FrameworkElement;
if (lastItemContainer == null)
{
//NO lastItemContainer YET, wait for next call
return;
}
var lastItemWidth = lastItemContainer.ActualWidth;
//3.5 get margin fix value
var rightMarginFixValue = sv.ActualWidth - lastItemWidth;
//3.6. fix "scroll last item into view" bug
ip.Margin = new Thickness(ip.Margin.Left,
ip.Margin.Top,
ip.Margin.Right + rightMarginFixValue, //APPLY FIX
ip.Margin.Bottom);
}
public static T GetParent<T>(DependencyObject reference) where T : class
{
var depObj = VisualTreeHelper.GetParent(reference);
if (depObj == null) return (T)null;
while (true)
{
var depClass = depObj as T;
if (depClass != null) return depClass;
depObj = VisualTreeHelper.GetParent(depObj);
if (depObj == null) return (T)null;
}
}
关于这个例子。
大多数检查和错误处理都被省略。
如果您覆盖ListView样式/模板，则必须相应地更改VisualTree搜索部分