在ListView的选定项内滚动

Question

在WPF-ListView控件上，所选项必须可视化一些附加细节。如果选择了项，则需要比ListView控件提供更多的空间。

默认情况下，不可能在选定项内滚动。向下滚动，它直接跳到下一项，并且不可能看到所选项的底部部分。

有人知道如何在所选项目中启用滚动吗？

下面的代码演示了这种行为。在实际代码中，所选项更复杂，但举个例子，所选项的大小在被选中时只会被修改：

XAML:

<Window x:Class="ListViewWithLargeSelectedItem.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="MainWindow" Height="300" Width="300">
<Grid>
    <ListView ItemsSource="{Binding Items}" SelectedItem="{Binding SelectedItem}" HorizontalContentAlignment="Stretch">
        <ListView.ItemTemplate>
            <DataTemplate>
                <Border x:Name="border" Padding="10" HorizontalAlignment="Stretch">
                    <TextBlock Text="{Binding Text}" />
                </Border>
                <DataTemplate.Triggers>
                    <DataTrigger Binding="{Binding IsSelected}"
                                             Value="true">
                        <Setter TargetName="border" Property="Padding"
                                        Value="40,200" />
                    </DataTrigger>
                </DataTemplate.Triggers>
            </DataTemplate>
        </ListView.ItemTemplate>
    </ListView>
</Grid>

​

代码背后：

public partial class MainWindow : Window
{
    private CustomItem _selectedItem;
    public CustomItem SelectedItem
    {
        get { return _selectedItem; }
        set
        {
            if (_selectedItem != null)
            {
                _selectedItem.IsSelected = false;
            }
            _selectedItem = value;
            _selectedItem.IsSelected = true;
        }
    }

    public List<CustomItem> Items
    {
        get { return (List<CustomItem>)GetValue(ItemsProperty); }
        set { SetValue(ItemsProperty, value); }
    }

    public static readonly DependencyProperty ItemsProperty =
            DependencyProperty.Register("Items", typeof(List<CustomItem>), typeof(MainWindow), new UIPropertyMetadata(null));

    public MainWindow()
    {
        InitializeComponent();
        Items = new List<CustomItem>();
        for (int i = 0; i < 10; i++)
        {
            Items.Add(new CustomItem() { IsSelected = false, Text = "ITEM " + i });             
        }
        DataContext = this;
    }
}

public class CustomItem : INotifyPropertyChanged
{
    public string Text { get; set; }
    private bool _isSelected;
    public bool IsSelected
    {
        get { return _isSelected; }
        set
        {
            if (_isSelected == value)
            {
                return;
            }

            _isSelected = value;
            NotifyOfPropertyChange("IsSelected");
        }
    }

    private void NotifyOfPropertyChange(string propertyName)
    {
        if (PropertyChanged != null)
        {
            PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
        }
    }


    public event PropertyChangedEventHandler PropertyChanged;
}

Answer 1

您的问题不是很清楚，但是如果您说您的ListView滚动使用整个项，并且希望它使用像素滚动，那么请在MSDN上查看 property页面。如果是这样的话，那么您只需要在您的ListView上将这个附加属性设置为ListView，以便能够顺利滚动：

<ListView ScrollViewer.CanContentScroll="False" ... />