回答編集履歴

- ちょっと苦労されているようなので、サンプルを書いてみました。

- NuGetで`Prism.Core`を入れてあります。

- ```C#

- using System.Collections.ObjectModel;

- using System.ComponentModel;

- using System.Windows;

- using System.Windows.Data;

- using Prism.Commands;

- using Prism.Mvvm;

-

- namespace Questions222623

- {

- internal class MainViewModel

- {

- public class ItemViewModel : BindableBase

- {

- private bool _Selected;

- public bool Selected { get => _Selected; set => SetProperty(ref _Selected, value); }

-

- private string _Name;

- public string Name { get => _Name; set => SetProperty(ref _Name, value); }

- }

-

- public ObservableCollection<ItemViewModel> Items { get; }

- public ICollectionView LeftView { get; }

- public ICollectionView RightView { get; }

- public DelegateCommand<ItemViewModel> Left2RightCommand { get; }

- public DelegateCommand<ItemViewModel> Right2LeftCommand { get; }

-

- public MainViewModel()

- {

- Items = new ObservableCollection<ItemViewModel>

- {

- new ItemViewModel() { Name = "C1", Selected = true },

- new ItemViewModel() { Name = "C2", Selected = false },

- new ItemViewModel() { Name = "C3", Selected = true },

- new ItemViewModel() { Name = "C4", Selected = true },

- new ItemViewModel() { Name = "C5", Selected = false },

- new ItemViewModel() { Name = "C6", Selected = true },

- };

-

- var cvs = new CollectionViewSource { Source = Items, };

- cvs.IsLiveFilteringRequested = true; // 変更があったときにフィルターを即時反映

- cvs.LiveFilteringProperties.Add(nameof(ItemViewModel.Selected)); // 変更を監視するプロパティ名

- LeftView = cvs.View;

- LeftView.Filter = x => (x as ItemViewModel).Selected == true;

-

- cvs = new CollectionViewSource { Source = Items, };

- cvs.IsLiveFilteringRequested = true;

- cvs.LiveFilteringProperties.Add(nameof(ItemViewModel.Selected));

- RightView = cvs.View;

- RightView.Filter = x => (x as ItemViewModel).Selected == false;

-

- Left2RightCommand = new DelegateCommand<ItemViewModel>(Left2rightCommandExecute);

- Right2LeftCommand = new DelegateCommand<ItemViewModel>((item) => { if(item != null) item.Selected = true; }); // ラムダでもよい

- }

-

- private void Left2rightCommandExecute(ItemViewModel item)

- {

- if(item != null)

- item.Selected = false;

- }

- }

-

- public partial class MainWindow : Window

- {

- public MainWindow() => InitializeComponent();

- }

- }

- ```

- ```xaml

- <Window

- x:Class="Questions222623.MainWindow"

- xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

- xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

- xmlns:local="clr-namespace:Questions222623"

- Title="MainWindow"

- Width="800"

- Height="450">

- <Window.DataContext>

- <local:MainViewModel />

- </Window.DataContext>

- <Grid>

- <Grid.ColumnDefinitions>

- <ColumnDefinition />

- <ColumnDefinition Width="Auto" />

- <ColumnDefinition />

- </Grid.ColumnDefinitions>

- <ListBox

- x:Name="listBox"

- DisplayMemberPath="Name"

- ItemsSource="{Binding LeftView}" />

- <StackPanel Grid.Column="1" VerticalAlignment="Center">

- <Button

- Margin="5"

- Padding="5"

- Command="{Binding Left2RightCommand}"

- CommandParameter="{Binding SelectedItem, ElementName=listBox}"

- Content="→" />

- <Button

- Margin="5"

- Padding="5"

- Command="{Binding Right2LeftCommand}"

- CommandParameter="{Binding SelectedItem, ElementName=listBox1}"

- Content="←" />

- </StackPanel>

- <ListBox

- x:Name="listBox1"

- Grid.Column="2"

- DisplayMemberPath="Name"

- ItemsSource="{Binding RightView}" />

- </Grid>

- </Window>

- ```

- 

- こういうイメージであっていますでしょうか？

-

- ---

-

- 別解としてドラッグ＆ドロップでの移動例も作ってみました。

- NuGetで`Prism.Core` `gong-wpf-dragdrop`を入れてあります。

- ```C#

- using System.Collections;

- using System.Collections.ObjectModel;

- using System.Windows;

- using GongSolutions.Wpf.DragDrop;

- using Prism.Mvvm;

-

- namespace Questions222623

- {

- internal class MainViewModel : IDropTarget

- {

- public class ItemViewModel : BindableBase

- {

- private string _Name;

- public string Name { get => _Name; set => SetProperty(ref _Name, value); }

- }

-

- public ObservableCollection<ItemViewModel> SelectedItems { get; }

- public ObservableCollection<ItemViewModel> UnselectedItems { get; }

-

- private readonly DefaultDropHandler defaultDropHandler = new DefaultDropHandler();

-

- public MainViewModel()

- {

- SelectedItems = new ObservableCollection<ItemViewModel>

- {

- new ItemViewModel() { Name = "C1", },

- new ItemViewModel() { Name = "C3", },

- new ItemViewModel() { Name = "C4", },

- new ItemViewModel() { Name = "C6", },

- };

- UnselectedItems = new ObservableCollection<ItemViewModel>

- {

- new ItemViewModel() { Name = "C2", },

- new ItemViewModel() { Name = "C5", },

- };

- }

-

- void IDropTarget.DragOver(IDropInfo dropInfo)

- {

- if(dropInfo.Data is ItemViewModel)

- {

- dropInfo.DropTargetAdorner = DropTargetAdorners.Insert;

- dropInfo.Effects = DragDropEffects.Move;

- }

- }

- void IDropTarget.Drop(IDropInfo dropInfo)

- {

- if(dropInfo.Data is ItemViewModel item)

- {

- if(dropInfo.DragInfo.SourceCollection != dropInfo.TargetCollection)

- {

- ((IList)dropInfo.DragInfo.SourceCollection).Remove(item);

- ((IList)dropInfo.TargetCollection).Insert(dropInfo.InsertIndex, item);

- }

- else

- {

- defaultDropHandler.Drop(dropInfo);

- }

- }

- }

- }

- public partial class MainWindow : Window

- {

- public MainWindow() => InitializeComponent();

- }

- }

- ```

-

- ```xaml

- <Window

- x:Class="Questions222623.MainWindow"

- xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

- xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

- xmlns:dd="urn:gong-wpf-dragdrop"

- xmlns:local="clr-namespace:Questions222623"

- Title="MainWindow"

- Width="800"

- Height="450">

- <Window.DataContext>

- <local:MainViewModel />

- </Window.DataContext>

- <Grid>

- <Grid.ColumnDefinitions>

- <ColumnDefinition />

- <ColumnDefinition />

- </Grid.ColumnDefinitions>

- <ListBox

- dd:DragDrop.DropHandler="{Binding}"

- dd:DragDrop.IsDragSource="True"

- dd:DragDrop.IsDropTarget="True"

- DisplayMemberPath="Name"

- ItemsSource="{Binding SelectedItems}" />

- <ListBox

- Grid.Column="1"

- dd:DragDrop.DropHandler="{Binding}"

- dd:DragDrop.IsDragSource="True"

- dd:DragDrop.IsDropTarget="True"

- DisplayMemberPath="Name"

- ItemsSource="{Binding UnselectedItems}" />

- </Grid>

- </Window>

- ```

-