C# 有没有办法跳转到LongListSelector的ListHeader?
我正在开发一个Windows Phone 8应用程序,我想实现一个按钮,允许我跳转到C# 有没有办法跳转到LongListSelector的ListHeader?,c#,xaml,windows-phone-8,longlistselector,C#,Xaml,Windows Phone 8,Longlistselector,我正在开发一个Windows Phone 8应用程序,我想实现一个按钮,允许我跳转到LongListSelector的ListHeader顶部(ListHeader包含一些我用来过滤内容的单选按钮)。有什么方法可以做到这一点吗?在按钮处理程序中,使用此方法从LongListSelector的模板中获取视口控件 public static T FindChild<T>(DependencyObject parent, string childName) where T : De
LongListSelector
的ListHeader
顶部(ListHeader
包含一些我用来过滤内容的单选按钮)。有什么方法可以做到这一点吗?在按钮处理程序中,使用此方法从LongListSelector的模板中获取视口控件
public static T FindChild<T>(DependencyObject parent, string childName) where T : DependencyObject
{
// Confirm parent and childName are valid.
if (parent == null)
{
return null;
}
T foundChild = null;
int childrenCount = VisualTreeHelper.GetChildrenCount(parent);
for (int i = 0; i < childrenCount; i++)
{
DependencyObject child = VisualTreeHelper.GetChild(parent, i);
// If the child is not of the request child type child
var childType = child as T;
if (childType == null)
{
// recursively drill down the tree
foundChild = FindChild<T>(child, childName);
// If the child is found, break so we do not overwrite the found child.
if (foundChild != null)
{
break;
}
}
else if (!string.IsNullOrEmpty(childName))
{
var frameworkElement = child as FrameworkElement;
// If the child's name is set for search
if (frameworkElement != null && frameworkElement.Name == childName)
{
// if the child's name is of the request name
foundChild = (T)child;
break;
}
// Need this in case the element we want is nested
// in another element of the same type
foundChild = FindChild<T>(child, childName);
}
else
{
// child element found.
foundChild = (T)child;
break;
}
}
return foundChild;
}
如果您想知道ViewPortControl来自何处,下面是LongListSelector
的样式
<Style x:Key="LongListSelectorStyle1" TargetType="phone:LongListSelector">
<Setter Property="Background" Value="Transparent"/>
<Setter Property="Foreground" Value="{StaticResource PhoneForegroundBrush}"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="phone:LongListSelector">
<Grid Background="{TemplateBinding Background}" d:DesignWidth="480" d:DesignHeight="800">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="ScrollStates">
<VisualStateGroup.Transitions>
<VisualTransition GeneratedDuration="00:00:00.5"/>
</VisualStateGroup.Transitions>
<VisualState x:Name="Scrolling">
<Storyboard>
<DoubleAnimation Duration="0" To="1" Storyboard.TargetProperty="Opacity" Storyboard.TargetName="VerticalScrollBar"/>
</Storyboard>
</VisualState>
<VisualState x:Name="NotScrolling"/>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Grid Margin="{TemplateBinding Padding}">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="auto"/>
</Grid.ColumnDefinitions>
<ViewportControl x:Name="ViewportControl" HorizontalContentAlignment="Stretch" VerticalAlignment="Top"/>
<ScrollBar x:Name="VerticalScrollBar" Grid.Column="1" Margin="4,0,4,0" Opacity="0" Orientation="Vertical"/>
</Grid>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
您是否尝试过使用LongListSelector.ScrollTo()
滚动到第一项?不确定这是否会将标题撞到视图中,但您可以尝试一下。@Pantelis,我有。虽然这确实会滚动到项目列表的顶部,但滚动的幅度不足以显示ListHeader。工作起来像个符咒!不能再奖励3小时,奖励你——这是你应得的!
<Style x:Key="LongListSelectorStyle1" TargetType="phone:LongListSelector">
<Setter Property="Background" Value="Transparent"/>
<Setter Property="Foreground" Value="{StaticResource PhoneForegroundBrush}"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="phone:LongListSelector">
<Grid Background="{TemplateBinding Background}" d:DesignWidth="480" d:DesignHeight="800">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="ScrollStates">
<VisualStateGroup.Transitions>
<VisualTransition GeneratedDuration="00:00:00.5"/>
</VisualStateGroup.Transitions>
<VisualState x:Name="Scrolling">
<Storyboard>
<DoubleAnimation Duration="0" To="1" Storyboard.TargetProperty="Opacity" Storyboard.TargetName="VerticalScrollBar"/>
</Storyboard>
</VisualState>
<VisualState x:Name="NotScrolling"/>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Grid Margin="{TemplateBinding Padding}">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="auto"/>
</Grid.ColumnDefinitions>
<ViewportControl x:Name="ViewportControl" HorizontalContentAlignment="Stretch" VerticalAlignment="Top"/>
<ScrollBar x:Name="VerticalScrollBar" Grid.Column="1" Margin="4,0,4,0" Opacity="0" Orientation="Vertical"/>
</Grid>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>