回答編集履歴

- VBがわからな過ぎて時間がかかってしまったのですが、一通り作ってみました。

- **注意**

- 面倒なのでボタンなんかは全部コードビハインドです^^;

- 筋悪（主に`Implements IEnumerable(Of TreeNode)`）なところもありますが、ほかにスマートな方法が思いつきませんでした。

- 一応動いていますが何かとんでもない間違いがあるかもしれません。

-

-

- ```xaml

- <Window

- x:Class="MainWindow"

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

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

- Width="800"

- Height="450">

- <DockPanel>

- <StackPanel DockPanel.Dock="Top" Orientation="Horizontal">

- <Button

- Margin="5"

- Click="AllCheckButton_Click"

- Content="全チェック" />

- <Button

- Margin="5"

- Click="AllUncheckButton_Click"

- Content="全アンチェック" />

- <Button

- Margin="5"

- Click="AllExpandButton_Click"

- Content="全展開" />

- <Button

- Margin="5"

- Click="AllContractButton_Click"

- Content="全畳む" />

- <Button

- Margin="5"

- Click="AddNodeButton_Click"

- Content="ノード追加" />

- </StackPanel>

- <TreeView x:Name="treeView" ItemsSource="{Binding Root.Children}">

- <TreeView.ItemTemplate>

- <HierarchicalDataTemplate ItemsSource="{Binding Children}">

- <StackPanel Orientation="Horizontal">

- <CheckBox

- Margin="5"

- VerticalContentAlignment="Center"

- IsChecked="{Binding IsChecked}" />

- <TextBlock Margin="5" Text="{Binding Name}" />

- <Button

- Margin="5"

- Click="ShowDetailButton_Click"

- Content="確認" />

- <Button

- Margin="5"

- Click="DeleteNodeButton_Click"

- Content="削除" />

- </StackPanel>

- </HierarchicalDataTemplate>

- </TreeView.ItemTemplate>

- <TreeView.ItemContainerStyle>

- <Style TargetType="{x:Type TreeViewItem}">

- <Setter Property="IsSelected" Value="{Binding IsSelected, Mode=TwoWay}" />

- <Setter Property="IsExpanded" Value="{Binding IsExpanded, Mode=TwoWay}" />

- </Style>

- </TreeView.ItemContainerStyle>

- </TreeView>

- </DockPanel>

- </Window>

- ```

-

- ```VB

- Imports System.Collections.ObjectModel

- Imports System.ComponentModel

- Imports System.Runtime.CompilerServices

-

- Class MainWindow

- Private ReadOnly vm As ViewModel

-

- Public Sub New()

- InitializeComponent()

- vm = New ViewModel

- DataContext = vm

- End Sub

-

- Private Sub AllCheckButton_Click(sender As Object, e As RoutedEventArgs)

- For Each node As TreeNode In AllNodes(vm.Root)

- node.IsChecked = True

- Next

- End Sub

-

- Private Sub AllUncheckButton_Click(sender As Object, e As RoutedEventArgs)

- For Each node As TreeNode In AllNodes(vm.Root)

- node.IsChecked = False

- Next

- End Sub

-

- Private Sub AllExpandButton_Click(sender As Object, e As RoutedEventArgs)

- For Each node As TreeNode In AllNodes(vm.Root)

- node.IsExpanded = True

- Next

- End Sub

-

- Private Sub AllContractButton_Click(sender As Object, e As RoutedEventArgs)

- For Each node As TreeNode In AllNodes(vm.Root)

- node.IsExpanded = False

- Next

- End Sub

-

- Private Sub ShowDetailButton_Click(sender As Object, e As RoutedEventArgs)

- Dim button = CType(sender, Button)

- Dim node = CType(button.DataContext, TreeNode)

-

- MessageBox.Show($"Name:{node.Name}{vbCrLf}IsSelected:{node.IsSelected}{vbCrLf}IsExpanded:{node.IsExpanded}{vbCrLf}IsChecked:{node.IsChecked}")

- End Sub

-

- Private Sub DeleteNodeButton_Click(sender As Object, e As RoutedEventArgs)

- Dim button = CType(sender, Button)

- Dim node = CType(button.DataContext, TreeNode)

-

- node.Parent.Remove(node)

- End Sub

-

- Private Sub AddNodeButton_Click(sender As Object, e As RoutedEventArgs)

- Dim node = TryCast(treeView.SelectedItem, TreeNode)

- If node Is Nothing Then

- vm.Root.Add(New TreeNode("NewNode"))

- Else

- node.Add(New TreeNode("NewNode"))

- End If

- End Sub

-

- '子孫を全列挙

- Private Function AllNodes(node As TreeNode) As IEnumerable(Of TreeNode)

- If node Is Nothing Then

- Return Enumerable.Empty(Of TreeNode)

- End If

- Return node.Concat(node.SelectMany(Function(x) AllNodes(x)))

- End Function

- End Class

-

- Class ViewModel

- Public Property Root As TreeNode 'Rootは表示せず子供から表示（追加・削除の簡便さのため）

-

- Public Sub New()

- Root = New TreeNode("Root") From {

- New TreeNode("Node1") From {

- New TreeNode("Node1-1"),

- New TreeNode("Node1-2") From {

- New TreeNode("Node1-2-1"),

- New TreeNode("Node1-2-2")

- }

- },

- New TreeNode("Node2") From {

- New TreeNode("Node2-1") From {

- New TreeNode("Node2-1-1"),

- New TreeNode("Node2-1-2")

- }

- }

- }

- End Sub

- End Class

-

-

- Public Class TreeNode

- Inherits Observable 'INotifyPropertyChangedのベース実装

- Implements IEnumerable(Of TreeNode) 'コレクション初期化子を使いたいので

-

- Public Property Name As String

- Get

- Return _Name

- End Get

- Set(value As String)

- [Set](_Name, value)

- End Set

- End Property

- Private _Name As String

-

- Public ReadOnly Property Children As ObservableCollection(Of TreeNode) = New ObservableCollection(Of TreeNode)

-

- Public Property IsSelected As Boolean

- Get

- Return _IsSelected

- End Get

- Set(value As Boolean)

- [Set](_IsSelected, value)

- End Set

- End Property

- Private _IsSelected As Boolean

-

- Public Property IsExpanded As Boolean

- Get

- Return _IsExpanded

- End Get

- Set(value As Boolean)

- [Set](_IsExpanded, value)

- End Set

- End Property

- Private _IsExpanded As Boolean

-

- Public Property IsChecked As Boolean

- Get

- Return _IsChecked

- End Get

- Set(value As Boolean)

- [Set](_IsChecked, value)

- End Set

- End Property

- Private _IsChecked As Boolean

-

-

- Friend Parent As TreeNode '追加・削除の簡便さのため親ノードが欲しい

-

-

- Sub New(name As String)

- _Name = name

- End Sub

-

- Public Sub Add(child As TreeNode)

- child.Parent = Me

- Children.Add(child)

- End Sub

-

- Public Sub Remove(child As TreeNode)

- Children.Remove(child)

- child.Parent = Nothing

- End Sub

-

- #Region "IEnumerable"

- Public Function GetEnumerator() As IEnumerator(Of TreeNode) Implements IEnumerable(Of TreeNode).GetEnumerator

- Return Children.GetEnumerator()

- End Function

-

- Private Function IEnumerable_GetEnumerator() As IEnumerator Implements IEnumerable.GetEnumerator

- Return GetEnumerator()

- End Function

- #End Region

- End Class

-

-

- 'INotifyPropertyChanged 定番実装

- 'https://github.com/microsoft/WindowsTemplateStudio/blob/dev/templates/Uwp/_comp/MVVMBasic/Project._VB/Helpers/Observable.vb

- Public Class Observable

- Implements INotifyPropertyChanged

- Public Event PropertyChanged As PropertyChangedEventHandler Implements INotifyPropertyChanged.PropertyChanged

- Friend Sub [Set](Of T)(ByRef storage As T, newValue As T, <CallerMemberName> Optional propertyName As String = Nothing)

- If Equals(storage, newValue) Then

- Return

- End If

- storage = newValue

- OnPropertyChanged(propertyName)

- End Sub

- Protected Sub OnPropertyChanged(propertyName As String)

- RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(propertyName))

- End Sub