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2023/07/17 05:45

投稿

TN8001

スコア9855

test CHANGED Viewed

@@ -1,451 +1,226 @@
 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#
+```cs
 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
+```xml
 <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 />
       <ColumnDefinition Width="Auto" />
-      <ColumnDefinition />
+      <ColumnDefinition />
     </Grid.ColumnDefinitions>
-    <ListBox
+    <ListBox
       x:Name="listBox"
-      DisplayMemberPath="Name"
+      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
+    <ListBox
       x:Name="listBox1"
       Grid.Column="2"
-      DisplayMemberPath="Name"
+      DisplayMemberPath="Name"
       ItemsSource="{Binding RightView}" />
   </Grid>
 </Window>
-```
+```
 ![イメージ説明](2d99cba7cf1f91078346bcf5a4292aa4.png)
 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#
+```cs
 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
+```xml
 <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 />
-      <ColumnDefinition />
+      <ColumnDefinition />
     </Grid.ColumnDefinitions>
-    <ListBox
+    <ListBox
       dd:DragDrop.DropHandler="{Binding}"
       dd:DragDrop.IsDragSource="True"
       dd:DragDrop.IsDropTarget="True"
-      DisplayMemberPath="Name"
+      DisplayMemberPath="Name"
       ItemsSource="{Binding SelectedItems}" />
-    <ListBox
+    <ListBox
       Grid.Column="1"
       dd:DragDrop.DropHandler="{Binding}"
       dd:DragDrop.IsDragSource="True"
       dd:DragDrop.IsDropTarget="True"
-      DisplayMemberPath="Name"
+      DisplayMemberPath="Name"
       ItemsSource="{Binding UnselectedItems}" />
   </Grid>
 </Window>
-```
+```
 ![イメージ説明](dc019f2128de1fbd553a69bfc6e24fb5.png)
 コードが長くなると本質がわかりにくくなるため、`CollectionViewSource`を使わずシンプルに`SelectedItems` `UnselectedItems`と2つに分けましたが、もちろん使っても構いません。