Windows Phone xaml Listview 隐藏最后一个分隔符答案

【问题标题】：Windows Phone xaml Listview hide last separatorWindows Phone xaml Listview 隐藏最后一个分隔符
【发布时间】：2015-10-09 07:45:54
【问题描述】：

在我的列表视图中，我有一个用户控件和一个行分隔符，我的列表视图绑定在我的可观察集合属性上，我的 xaml 是：

<ListView ItemsSource="{Binding Path=ListaItinerari}" SelectedItem="{Binding ItinerarioSelezionato, Mode=TwoWay}" FontFamily="Global User Interface">
                        <ListView.ItemTemplate>
                            <DataTemplate>
                                <StackPanel>
                                    <UserControls:ItinerarioItemControl DataContext="{Binding}" />                                    
                                    <Line Margin="0,5,0,5" Stretch="Fill" Stroke="{StaticResource LineThemeBrush}" X2="1"/>
                                </StackPanel>
                            </DataTemplate>
                        </ListView.ItemTemplate>
                    </ListView>

我想隐藏最后一行分隔符。我用谷歌搜索了，但我什么也没找到

【问题讨论】：

标签： c# wpf xaml listview windows-phone-8.1

【解决方案1】：

只是一个建议，但最好将分隔符放在顶部（因此在您的用户控件上方）。

然后使用转换器对分隔符的可见性属性进行绑定。您传递项目索引，如果项目索引为 1，则隐藏分隔符，否则显示。

要获取项目的索引，请查看此处的示例：http://www.bendewey.com/index.php/523/alternating-row-color-in-windows-store-listview

【讨论】：

你不明白我的回答...把分隔符放在上面就不再是最后一个了！但还会有第一次。但这更容易被发现和隐藏。
是的，我现在明白了.. 这是个好主意，但是他所要求的也可以使用附加属性来实现..

【解决方案2】：

我已经能够使用 WPF 中的附加属性来做到这一点

 public class IndexItemHelper
{
    #region ListIndexer

    /// <summary>
    /// ListIndexer Attached Dependency Property
    /// </summary>
    public static readonly DependencyProperty ListIndexerProperty =
        DependencyProperty.RegisterAttached("ListIndexer", typeof(List<ListItem>), typeof(IndexItemHelper),
            new FrameworkPropertyMetadata((List<ListItem>)null,
                new PropertyChangedCallback(OnListIndexerChanged)));

    /// <summary>
    /// Gets the ListIndexer property. This dependency property 
    /// indicates ....
    /// </summary>
    public static List<ListItem> GetListIndexer(DependencyObject d)
    {
        return (List<ListItem>)d.GetValue(ListIndexerProperty);
    }

    /// <summary>
    /// Sets the ListIndexer property. This dependency property 
    /// indicates ....
    /// </summary>
    public static void SetListIndexer(DependencyObject d, List<ListItem> value)
    {
        d.SetValue(ListIndexerProperty, value);
    }

    /// <summary>
    /// Handles changes to the ListIndexer property.
    /// </summary>
    private static void OnListIndexerChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        List<ListItem> oldListIndexer = (List<ListItem>)e.OldValue;
        List<ListItem> newListIndexer = (List<ListItem>)d.GetValue(ListIndexerProperty);
        UpdateDependencyObject(d);
    }

    #endregion


    #region ItemIndexOf

    /// <summary>
    /// ItemIndexOf Attached Dependency Property
    /// </summary>
    public static readonly DependencyProperty ItemIndexOfProperty =
        DependencyProperty.RegisterAttached("ItemIndexOf", typeof(object), typeof(IndexItemHelper),
            new FrameworkPropertyMetadata((object)null,
                new PropertyChangedCallback(OnItemIndexOfChanged)));

    /// <summary>
    /// Gets the ItemIndexOf property. This dependency property 
    /// indicates ....
    /// </summary>
    public static object GetItemIndexOf(DependencyObject d)
    {
        return (object)d.GetValue(ItemIndexOfProperty);
    }

    /// <summary>
    /// Sets the ItemIndexOf property. This dependency property 
    /// indicates ....
    /// </summary>
    public static void SetItemIndexOf(DependencyObject d, object value)
    {
        d.SetValue(ItemIndexOfProperty, value);
    }

    /// <summary>
    /// Handles changes to the ItemIndexOf property.
    /// </summary>
    private static void OnItemIndexOfChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        object oldItemIndexOf = (object)e.OldValue;
        object newItemIndexOf = (object)d.GetValue(ItemIndexOfProperty);
        UpdateDependencyObject(d);
    }

    #endregion

    public static void UpdateDependencyObject(DependencyObject d)
    {
        var itemToGetIndexOf = GetItemIndexOf(d) as ListItem;
        var listToGetIndexFrom = GetListIndexer(d);
        if (itemToGetIndexOf == null || (listToGetIndexFrom == null || !listToGetIndexFrom.Any())) return;

        if (listToGetIndexFrom.IndexOf(itemToGetIndexOf) == (listToGetIndexFrom.Count - 1))
        {
            //this is the last line item
            var line = d as Line;
            if(line != null) line.Visibility = Visibility.Collapsed;
        }
        else
        {
            var line = d as Line;
            if (line != null) line.Visibility = Visibility.Visible;
        }
    }
}

附加属性的使用：

<Grid x:Name="Main">
    <ListView ItemsSource="{Binding ListaItinerarie}">
        <ListView.ItemTemplate>
            <DataTemplate>
                <StackPanel>
                    <TextBlock Text="{Binding Name}"></TextBlock>
                    <Line Margin="0,5,0,5" Stretch="Fill" Stroke="Red" X2="1" stackoverflow:IndexItemHelper.ItemIndexOf="{Binding }" stackoverflow:IndexItemHelper.ListIndexer="{Binding DataContext.ListaItinerarie, ElementName=Main}"/>
                </StackPanel>
            </DataTemplate>
        </ListView.ItemTemplate>
    </ListView>
</Grid>

每当列表或项目绑定发生变化时，它都会更新...

更新：在 windows phone 中使用“PropertyMetadata”代替“FrameworkPropertyMetadata”

【讨论】：

抱歉，Windows phone 8.1 xaml 中的 FrameworkPropertyMetadata 类型未找到
改用 PropertyMetadata！