Winrt MVVMLight使用参数在listItemClick上导航

Question

我在Windows 8.1应用程序中使用MVVMlight。我想在单击列表项时导航到新视图，并将单击的项目作为参数传递。

我已经定义了一个附加属性，如：

public static class ItemClickCommand
{
    public static readonly DependencyProperty CommandProperty =
        DependencyProperty.RegisterAttached("Command", typeof(ICommand),
        typeof(ItemClickCommand), new PropertyMetadata(null, OnCommandPropertyChanged));

    public static void SetCommand(DependencyObject d, ICommand value)
    {
        d.SetValue(CommandProperty, value);
    }

    public static ICommand GetCommand(DependencyObject d)
    {
        return (ICommand)d.GetValue(CommandProperty);
    }

    private static void OnCommandPropertyChanged(DependencyObject d,
        DependencyPropertyChangedEventArgs e)
    {
        var control = d as ListViewBase;
        if (control != null)
            control.ItemClick += OnItemClick;
    }

    private static void OnItemClick(object sender, ItemClickEventArgs e)
    {
        var control = sender as ListViewBase;
        var command = GetCommand(control);

        if (command != null && command.CanExecute(e.ClickedItem))
            command.Execute(e.ClickedItem);
    }
}

视图中的xaml如下所示：

<GridView
                        ItemsSource="{Binding Source={StaticResource ItemsSource}}"
                        ItemTemplate="{StaticResource itemsTemplate}"
                        SelectionMode="None"
                        helpers:ItemClickCommand.Command="{Binding ItemClicked}"
                        >
                    </GridView>

视图模型：

private RelayCommand<Item> _ItemClicked;
    public RelayCommand<Item> ItemClicked 
    {
        get 
        {
            if (_ItemClicked == null)
            {
                _ItemClicked = new RelayCommand<Item>(
                    (item) =>
                    {
                        _navigationService.Navigate(typeof(ItemsPage));
                    });
            }

            return _ItemClicked;
        }        
    }

单击网格项时没有任何反应。

Answer 1

我使用了本教程：Laurent Bugnion

http://msdn.microsoft.com/en-us/magazine/dn237302.aspx