如何使用CommandParameter发送列表

Question

我有一个ListView，并且由于它支持多个选择，所以我有一个按钮，用于收集所有SelectedItems并使用CommandParameter传递它们。对此我非常陌生，我真的不知道该如何使用参数。将列表传递给ViewModel后，如何访问该列表？请参见以下代码：

查看

<ListView x:Name="ListView"  ItemsSource="{Binding myModel.myCollection}">
<Button Command="{Binding SelectBtnOnClickCommand}" CommandParameter="{Binding SelectedItems, ElementName=ListView}">

ViewModel

public class SiteListViewModel
{
    public ICommand AddBtnOnClickCommand { get; }
    private ICommand _selectBtnOnClickCommand;
    public ICommand SelectBtnOnClickCommand
    {
        get
        {
            if (_selectBtnOnClickCommand == null)
                _selectBtnOnClickCommand = new RelayCommand(o =>
                {
                    var selectedSites = (o as IList);
                    if (selectedSites != null)
                    {
                        foreach (var model in selectedSites.OfType<SiteUrlsModel>())
                        {
                            //
                        }
                    }
                });
            return _selectBtnOnClickCommand;
        }
    }

    private readonly IWindowService _windowService;
    public static SiteUrlsModel SiteUrlsModel { get; } = new SiteUrlsModel();
    public ObservableCollection<SiteUrlsModel> SelectedSites { get; set; }
    private readonly ClientContext _clientContext = new ClientContext();


    public SiteListViewModel(IWindowService windowService)
    {
        _windowService = windowService;
        AddBtnOnClickCommand = new RelayCommand(AddBtnOnClick);
        //SelectBtnOnClickCommand = new RelayCommand(SelectBtnOnClick);
        RefreshSiteListView();
    }

    public void AddBtnOnClick()
    {
        _addSiteWindow = new AddSite(this);
        _addSiteWindow.Show();
    }

    public void SelectBtnOnClick(ObservableCollection<SiteUrlsModel> checkedList)
    {
        foreach (var site in checkedList)
        {
            site.IsChecked = true;
        }
    }    

    public void RefreshSiteListView()
    {
        var siteUrlsCollection = new ObservableCollection<SiteUrlsModel>(_clientContext.PopulateList());
        SiteUrlsModel.SiteUrlsCollection = siteUrlsCollection;
    }       
}

CommandClass

public class RelayCommand : ICommand
    {

        private readonly Action<object> _actionWithObject;

        public RelayCommand(Action<object> actionWithObject)
        {
            _actionWithObject = actionWithObject;
        }

        public bool CanExecute(object parameter)
        {
            return true;
        }

        public void Execute(object parameter)
        {
            if (parameter != null)
                _actionWithObject(parameter);
            else
                _actionWithObject(parameter);
        }

        public event EventHandler CanExecuteChanged;
    }

Answer 1

ListView.SelectedItems是IList：

private ICommand _selectBtnOnClickCommand;
public ICommand SelectBtnOnClickCommand
{
    get
    {
        if (_selectBtnOnClickCommand == null)
            _selectBtnOnClickCommand = new RelayCommand(o =>
            {
                var selectedSites = (o as IList);
                if (selectedSites != null)
                {
                    foreach (var model in selectedSites.OfType<SiteUrlsModel>())
                    {
                        //
                    }
                }
            });
        return _selectBtnOnClickCommand;
    }
}