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我有两个 ListView，第一个是启用 MultipleSelection 的 ListView。当用户从第一个 ListView 中单击一个项目时，它会被添加到第二个 ListView 中，当他从第一个 listView 中取消选择一个项目时，它会从第二个 ListView 中删除。

我现在的问题是我希望用户能够从第二个 ListView（已经实现）中删除 ListViewItem，并在第一个 ListView 中取消选择该项目。我可以删除该项目没问题只需要在第一个 ListView 中取消选择该项目的方法

  <ListView.ItemTemplate>
                <DataTemplate >
                    <RelativePanel >
                        <TextBlock Text="{Binding Name}" RelativePanel.LeftOf="MoveButton"/>
                        <Button  Name="MoveButton" Command="{Binding ElementName=NaughtySelectionList, Path=DataContext.MoveCommand}" 
                                 CommandParameter="{Binding Id}"  Content="+"  
                                 Style="{StaticResource ButtonClearStyle}"
                                 RelativePanel.AlignRightWithPanel="True" 
                                 RelativePanel.AlignTopWithPanel="True"/>
                    </RelativePanel>
                </DataTemplate>
            </ListView.ItemTemplate> 

        </ListView>
        <ListView Name="NaughytSelectedList" ItemsSource="{Binding SelectedNaughtyChildren}">
            <ListView.ItemTemplate>
                <DataTemplate >
                    <RelativePanel >
                        <TextBlock Text="{Binding Name}" RelativePanel.LeftOf="MoveBackButton"  />
                        <Button Name="MoveBackButton" 
                                Command="{Binding ElementName=NaughytSelectedList, Path=DataContext.MoveBackCommand}"
                                CommandParameter="{Binding Id}"  Content="✖"  
                                Style="{StaticResource ButtonClearStyle}" 
                                RelativePanel.AlignRightWithPanel="True" RelativePanel.AlignTopWithPanel="True" />
                    </RelativePanel>
                </DataTemplate>
            </ListView.ItemTemplate>
        </ListView>

视图模型

    private Child selectedChild ;
    public Child SelectedChild
    {
        get { return selectedChild; }
        set { selectedChild = value;


            base.RaisePropertyChanged();
        }
    }


    private DelegateCommand<IList<Object>> selectionChangedCommand;
    public DelegateCommand<IList<Object>> SelectionChangedCommand
        => selectionChangedCommand ?? (selectionChangedCommand = new DelegateCommand<IList<object>>(AddToNaughty, CanAddToNaughty));
    private bool CanAddToNaughty(IList<object> arg)
    {
        return true;

    }

    private void AddToNaughty(IList<object> currentSelection)
{

        var currentSelectionCollection= new ObservableCollection<Child>();

        foreach (var child in currentSelection )
        {
            currentSelectionCollection.Add(child as Child);  
        }

        foreach (var child in currentSelectionCollection)
        {
            if (!SelectedNaughtyChildren.Contains(child))
                SelectedNaughtyChildren.Add(child);
        }


        //Check if an item has been deselected.
        var copyOfSelectedNaughtyChildren =  new ObservableCollection<Child>(SelectedNaughtyChildren);
            var deselectedItems = from child in copyOfSelectedNaughtyChildren
                            where !currentSelectionCollection.Contains(child)
                            select child;


        //Remove the DeselectedItem.
        foreach (var child in deselectedItems)
        {
            SelectedNaughtyChildren.Remove(child);
        }       
    }

    private DelegateCommand<int> moveBackCommand;
    public DelegateCommand<int> MoveBackCommand
        => moveBackCommand ?? (moveBackCommand = new DelegateCommand<int>(DeleteChild, CanDeleteChild));



    private bool CanDeleteChild(int arg)
    {
        return true;
    }

    private void DeleteChild(int id)
    {
        var childMatch = from child in SelectedNaughtyChildren
                         where child.Id == id
                         select child;

        var childToRemove = childMatch.First();
        if (childToRemove != null)
            SelectedNaughtyChildren.Remove(childToRemove);
         //Hear I want to deselect the item from the first ListView
         // setting selected item to null deselects all the items.
        SelectedChild = null;

    }
}

编辑：我添加了一些图像来显示我想要的功能。我有这个工作，但只能使用后面的代码。如果可能的话，我想在 ViewModel 中实现这一点。

所以用户选择了一些项目，它们出现在右侧的 ListView 中

当用户从右侧删除和项目时，它会在左侧取消选择

4

1 回答 1

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您必须从SelectedItems列表中删除该项目firstlistview 这是代码

foreach(var item in FirstListView.Items)//or use firstlistview observable collection
{
//Compare item to be deselected
  if(childToRemove  == item)
     FirstListView.SelectedItems.Remove(item);
}
于 2016-05-30T05:04:51.463 回答