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2023/07/23 05:14

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TN8001

スコア10111

answer CHANGED Viewed

@@ -1,143 +1,143 @@
-`DataTemplateSelector`は、`ViewModel`が継承するようなものではありません（通常`View`層に単体で存在します）
-[データ オブジェクトのプロパティに基づく DataTemplate の選択 - WPF | Microsoft Docs](https://docs.microsoft.com/ja-jp/dotnet/framework/wpf/data/data-templating-overview#choosing-a-datatemplate-based-on-properties-of-the-data-object)
-作りがだいぶ違いますが、要は「入力値に対して適当なテンプレートを選択して返す」ってだけです（`IValueConverter`なんかもそう）
-[方法: バインドされたデータを変換する - WPF | Microsoft Docs](https://docs.microsoft.com/ja-jp/dotnet/framework/wpf/data/how-to-convert-bound-data)
-参考サイトのものを`Livet`で作るとすると、こんな感じでしょうか（`namespace`ごとにまとめていますが、別ファイルです）
-ついでに名前を大文字にする~~しょうもない~~コンバーター例（`UppercaseConverter`）も入れました。
-```xaml
-<Window
-  x:Class="Questions289487.Views.MainWindow"
-  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
-  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-  xmlns:behaviors="http://schemas.microsoft.com/xaml/behaviors"
-  xmlns:l="http://schemas.livet-mvvm.net/2011/wpf"
-  xmlns:v="clr-namespace:Questions289487.Views"
-  xmlns:vm="clr-namespace:Questions289487.ViewModels"
-  Width="525"
-  Height="350">
-  <Window.DataContext>
-    <vm:MainWindowViewModel />
-  </Window.DataContext>
-  <behaviors:Interaction.Triggers>
-    <behaviors:EventTrigger EventName="ContentRendered">
-      <l:LivetCallMethodAction MethodName="Initialize" MethodTarget="{Binding}" />
-    </behaviors:EventTrigger>
-    <behaviors:EventTrigger EventName="Closed">
-      <l:DataContextDisposeAction />
-    </behaviors:EventTrigger>
-  </behaviors:Interaction.Triggers>
-  <Window.Resources>
-    <DataTemplate x:Key="MyTemplate1">
-      <TextBlock Background="Aqua" Text="{Binding Name}" />
-    </DataTemplate>
-    <DataTemplate x:Key="MyTemplate2">
-      <TextBlock Background="Gold" Text="{Binding Name}" />
-    </DataTemplate>
-    <v:ComboHeaderTemplateSelector
-      x:Key="MySelector"
-      Template1="{StaticResource MyTemplate1}"
-      Template2="{StaticResource MyTemplate2}" />
-    <v:UppercaseConverter x:Key="UppercaseConverter" />
-  </Window.Resources>
-  <StackPanel Margin="10">
-    <ComboBox ItemsSource="{Binding View}">
-      <ComboBox.GroupStyle>
-        <GroupStyle HeaderTemplateSelector="{StaticResource MySelector}" />
-      </ComboBox.GroupStyle>
-      <ComboBox.ItemTemplate>
-        <DataTemplate>
-          <TextBlock Text="{Binding Title, Converter={StaticResource UppercaseConverter}}" />
-        </DataTemplate>
-      </ComboBox.ItemTemplate>
-    </ComboBox>
-  </StackPanel>
-</Window>
-```
-```C#
-using System.Collections.Generic;
-using System.Windows.Data;
-using Livet;
-namespace Questions289487.ViewModels
-{
-    // これはModelsにあるべきもの？まあ本題ではないので。。
-    public class ComboItem
-    {
-        public string Title { get; set; }
-        public string Category { get; set; }
-    }
-    public class MainWindowViewModel : ViewModel
-    {
-        private ListCollectionView _View;
-        public ListCollectionView View
-        {
-            get => _View;
-            set => RaisePropertyChangedIfSet(ref _View, value);
-        }
-        public void Initialize()
-        {
-            var items = new List<ComboItem>
-            {
-                new ComboItem() { Title = "ichiro", Category = "CategoryA" },
-                new ComboItem() { Title = "jiro", Category = "CategoryA" },
-                new ComboItem() { Title = "saburo", Category = "CategoryA" },
-                new ComboItem() { Title = "momotaro", Category = "CategoryB" },
-                new ComboItem() { Title = "kintaro", Category = "CategoryB" },
-            };
-            View = new ListCollectionView(items);
-            View.GroupDescriptions.Add(new PropertyGroupDescription("Category"));
-        }
-    }
-}
-```
-```C#
-using System;
-using System.Globalization;
-using System.Windows;
-using System.Windows.Controls;
-using System.Windows.Data;
-namespace Questions289487.Views
-{
-    public partial class MainWindow : Window
-    {
-        public MainWindow() => InitializeComponent();
-    }
-    public class ComboHeaderTemplateSelector : DataTemplateSelector
-    {
-        public DataTemplate Template1 { get; set; }
-        public DataTemplate Template2 { get; set; }
-        public override DataTemplate SelectTemplate(object item, DependencyObject container)
-        {
-            var group = (CollectionViewGroup)item;
-            if("CategoryA" == group.Name.ToString()) return Template1;
-            else return Template2;
-        }
-    }
-    public class UppercaseConverter : IValueConverter
-    {
-        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
-        {
-            var s = (string)value;
-            return s.ToUpper();
-        }
-        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) => throw new NotImplementedException();
-    }
-}
+`DataTemplateSelector`は、`ViewModel`が継承するようなものではありません（通常`View`層に単体で存在します）
+[データ オブジェクトのプロパティに基づく DataTemplate の選択 - WPF | Microsoft Docs](https://docs.microsoft.com/ja-jp/dotnet/framework/wpf/data/data-templating-overview#choosing-a-datatemplate-based-on-properties-of-the-data-object)
+作りがだいぶ違いますが、要は「入力値に対して適当なテンプレートを選択して返す」ってだけです（`IValueConverter`なんかもそう）
+[方法: バインドされたデータを変換する - WPF | Microsoft Docs](https://docs.microsoft.com/ja-jp/dotnet/framework/wpf/data/how-to-convert-bound-data)
+参考サイトのものを`Livet`で作るとすると、こんな感じでしょうか（`namespace`ごとにまとめていますが、別ファイルです）
+ついでに名前を大文字にする~~しょうもない~~コンバーター例（`UppercaseConverter`）も入れました。
+```xml
+<Window
+  x:Class="Questions289487.Views.MainWindow"
+  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+  xmlns:behaviors="http://schemas.microsoft.com/xaml/behaviors"
+  xmlns:l="http://schemas.livet-mvvm.net/2011/wpf"
+  xmlns:v="clr-namespace:Questions289487.Views"
+  xmlns:vm="clr-namespace:Questions289487.ViewModels"
+  Width="525"
+  Height="350">
+  <Window.DataContext>
+    <vm:MainWindowViewModel />
+  </Window.DataContext>
+  <behaviors:Interaction.Triggers>
+    <behaviors:EventTrigger EventName="ContentRendered">
+      <l:LivetCallMethodAction MethodName="Initialize" MethodTarget="{Binding}" />
+    </behaviors:EventTrigger>
+    <behaviors:EventTrigger EventName="Closed">
+      <l:DataContextDisposeAction />
+    </behaviors:EventTrigger>
+  </behaviors:Interaction.Triggers>
+  <Window.Resources>
+    <DataTemplate x:Key="MyTemplate1">
+      <TextBlock Background="Aqua" Text="{Binding Name}" />
+    </DataTemplate>
+    <DataTemplate x:Key="MyTemplate2">
+      <TextBlock Background="Gold" Text="{Binding Name}" />
+    </DataTemplate>
+    <v:ComboHeaderTemplateSelector
+      x:Key="MySelector"
+      Template1="{StaticResource MyTemplate1}"
+      Template2="{StaticResource MyTemplate2}" />
+    <v:UppercaseConverter x:Key="UppercaseConverter" />
+  </Window.Resources>
+  <StackPanel Margin="10">
+    <ComboBox ItemsSource="{Binding View}">
+      <ComboBox.GroupStyle>
+        <GroupStyle HeaderTemplateSelector="{StaticResource MySelector}" />
+      </ComboBox.GroupStyle>
+      <ComboBox.ItemTemplate>
+        <DataTemplate>
+          <TextBlock Text="{Binding Title, Converter={StaticResource UppercaseConverter}}" />
+        </DataTemplate>
+      </ComboBox.ItemTemplate>
+    </ComboBox>
+  </StackPanel>
+</Window>
+```
+```cs
+using System.Collections.Generic;
+using System.Windows.Data;
+using Livet;
+namespace Questions289487.ViewModels
+{
+    // これはModelsにあるべきもの？まあ本題ではないので。。
+    public class ComboItem
+    {
+        public string Title { get; set; }
+        public string Category { get; set; }
+    }
+    public class MainWindowViewModel : ViewModel
+    {
+        private ListCollectionView _View;
+        public ListCollectionView View
+        {
+            get => _View;
+            set => RaisePropertyChangedIfSet(ref _View, value);
+        }
+        public void Initialize()
+        {
+            var items = new List<ComboItem>
+            {
+                new ComboItem() { Title = "ichiro", Category = "CategoryA" },
+                new ComboItem() { Title = "jiro", Category = "CategoryA" },
+                new ComboItem() { Title = "saburo", Category = "CategoryA" },
+                new ComboItem() { Title = "momotaro", Category = "CategoryB" },
+                new ComboItem() { Title = "kintaro", Category = "CategoryB" },
+            };
+            View = new ListCollectionView(items);
+            View.GroupDescriptions.Add(new PropertyGroupDescription("Category"));
+        }
+    }
+}
+```
+```cs
+using System;
+using System.Globalization;
+using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Data;
+namespace Questions289487.Views
+{
+    public partial class MainWindow : Window
+    {
+        public MainWindow() => InitializeComponent();
+    }
+    public class ComboHeaderTemplateSelector : DataTemplateSelector
+    {
+        public DataTemplate Template1 { get; set; }
+        public DataTemplate Template2 { get; set; }
+        public override DataTemplate SelectTemplate(object item, DependencyObject container)
+        {
+            var group = (CollectionViewGroup)item;
+            if("CategoryA" == group.Name.ToString()) return Template1;
+            else return Template2;
+        }
+    }
+    public class UppercaseConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            var s = (string)value;
+            return s.ToUpper();
+        }
+        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) => throw new NotImplementedException();
+    }
+}
 ```