10

我正在尝试将 ListViewItem 的 IsSelected 属性绑定到 ViewModel 中的属性。它在 WPF 中运行良好，但在 Windows RT 中，IsSelected 属性永远不会被设置。

public class Item : INotifyPropertyChanged
{
    private readonly string name;
    private bool isSelected;
    public event PropertyChangedEventHandler PropertyChanged;

    public bool IsSelected
    {
        get { return isSelected; }
        set { isSelected = value; RaisePropertyChanged("IsSelected"); }
    }

    public string Name { get { return name; } }

    public Item(string name)
    {
        this.name = name;
    }

    protected void RaisePropertyChanged(string propertyName)
    {
        var handler = PropertyChanged;
        if (handler != null)
            handler.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }
}

public class ViewModel
{
    private readonly ObservableCollection<Item> items = new ObservableCollection<Item>(Enumerable.Range(0, 10).Select(p => new Item(p.ToString())));
    public ObservableCollection<Item> Items { get { return items; } }
}

public sealed partial class MainPage : Page
{
    public MainPage()
    {
        this.InitializeComponent();
        DataContext = new ViewModel();
    }
}

xml:

<StackPanel Orientation="Horizontal">
    <ListView ItemsSource="{Binding Path=Items}" SelectionMode="Multiple">
        <ListView.ItemContainerStyle>
            <Style TargetType="ListViewItem">
                <Setter Property="IsSelected" Value="{Binding Path=IsSelected, Mode=TwoWay}"/>
            </Style>
        </ListView.ItemContainerStyle>
    </ListView>
    <ListView.ItemTemplate>
        <DataTemplate>
            <TextBlock Text="{Binding Path=Name}"/>
         </DataTemplate>
     </ListView.ItemTemplate>
</StackPanel>

我可以单击屏幕上的项目，但 IsSelected 属性没有传播到 ViewModel。任何想法为什么？

4

2 回答 2

3

从 Windows 8.0 开始，WinRT 根本不支持 setter 中的绑定。必应寻找解决方法。

于 2013-04-13T23:30:26.290 回答
3

一个很好且简单的方法是继承 ListView

public class MyListView : ListView
    {
        protected override void PrepareContainerForItemOverride(Windows.UI.Xaml.DependencyObject element, object item)
        {
            base.PrepareContainerForItemOverride(element, item);
            // ...
            ListViewItem listItem = element as ListViewItem;
            Binding binding = new Binding();
            binding.Mode = BindingMode.TwoWay;
            binding.Source = item;
            binding.Path = new PropertyPath("Selected");
            listItem.SetBinding(ListViewItem.IsSelectedProperty, binding);
        }
    }

或者，您似乎也可以使用WinRT XAML Toolkit来完成。

<ListView
            x:Name="lv"
            Grid.Row="1"
            Grid.Column="1"
            SelectionMode="Multiple"
            HorizontalAlignment="Left"
            Width="500">
            <ListView.ItemTemplate>
                <DataTemplate>
                    <TextBlock
                        Extensions:ListViewItemExtensions.IsSelected="{Binding IsSelected}"
                        Extensions:ListViewItemExtensions.IsEnabled="{Binding IsEnabled}"
                        Text="{Binding Text}"
                        Margin="15,5"
                        FontSize="36" />
                </DataTemplate>
            </ListView.ItemTemplate>
        </ListView>

就个人而言，我使用了第一种方法，因为它更灵活，并且我需要绑定一些自动化属性。

感谢 ForInfo 和 ehuna： http ://social.msdn.microsoft.com/Forums/windowsapps/en-US/9a0adf35-fdad-4419-9a34-a9dac052a2e3/listviewitemisselected-data-binding-in-style-setter-is-不工作

于 2013-07-18T11:12:20.677 回答