回答編集履歴

  追記では収まらないので、別回答にさせていただきます。

 

  やっていることは前の回答と同じなのですが、より具体的かつシンプルになっています。

  そのためまったく汎用的ではありません。

 

  <Window x:Class="Questions355107.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="clr-namespace:Questions355107" Width="{Binding Settings.Window.Width, Mode=TwoWay}"

  Height="{Binding Settings.Window.Height, Mode=TwoWay}" Left="{Binding Settings.Window.Left, Mode=TwoWay}" Top="{Binding Settings.Window.Top, Mode=TwoWay}">

  <Window.DataContext>

  <local:ViewModel />

  </Window.DataContext>

  <Window.Resources>

  <DataTemplate DataType="{x:Type local:ContentModel}">

  <Border x:Name="b" Background="{Binding Brush}" SizeChanged="Border_SizeChanged">

  <Grid>

  <TextBlock>

  <TextBlock.Text>

  <MultiBinding StringFormat="{}{0:f2}, {1:f2}">

  <Binding ElementName="b" Path="ActualWidth" />

  <Binding ElementName="b" Path="ActualHeight" />

  </MultiBinding>

  </TextBlock.Text>

  </TextBlock>

  <TextBlock HorizontalAlignment="Center" VerticalAlignment="Center" FontSize="30" FontWeight="Bold" Text="{Binding Text}" />

  </Grid>

  </Border>

 

  <DataTemplate x:Key="OnePane">

  <ContentControl Content="{Binding Contents[0]}" />

  <DataTemplate x:Key="TwoPane">

  <local:TwoPane />

  <DataTemplate x:Key="ThreePane">

  <local:ThreePane />

  <DataTemplate x:Key="FourPane">

  <local:FourPane />

 

  <Style TargetType="GridSplitter">

  <Setter Property="HorizontalAlignment" Value="Stretch" />

  </Style>

 

  <Style x:Key="PaneStyle" TargetType="{x:Type ContentControl}">

  <Style.Triggers>

  <DataTrigger Binding="{Binding SelPane}" Value="1">

  <Setter Property="ContentTemplate" Value="{StaticResource OnePane}" />

  <DataTrigger Binding="{Binding SelPane}" Value="2">

  <Setter Property="ContentTemplate" Value="{StaticResource TwoPane}" />

  <DataTrigger Binding="{Binding SelPane}" Value="3">

  <Setter Property="ContentTemplate" Value="{StaticResource ThreePane}" />

  <DataTrigger Binding="{Binding SelPane}" Value="4">

  <Setter Property="ContentTemplate" Value="{StaticResource FourPane}" />

  </Style.Triggers>

  </Style>

 

  <Style x:Key="RadioListBoxItem" TargetType="{x:Type ListBoxItem}">

  <Setter Property="Template">

  <Setter.Value>

  <ControlTemplate TargetType="{x:Type ListBoxItem}">

  <RadioButton MinWidth="30" Content="{TemplateBinding Content}" IsChecked="{Binding IsSelected, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource {x:Type ToggleButton}}" />

  </ControlTemplate>

  </Setter.Value>

  </Setter>

  </Style>

  </Window.Resources>

  <DockPanel>

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

  <Button Command="{Binding Save}" Content="Save" />

  <Button Command="{Binding Load}" Content="Load" />

  <ListBox Padding="-1" BorderThickness="0" ItemContainerStyle="{StaticResource RadioListBoxItem}" ItemsSource="{Binding Panes}" SelectedItem="{Binding SelPane}">

  <ListBox.ItemsPanel>

  <ItemsPanelTemplate>

  <StackPanel Orientation="Horizontal" />

  </ItemsPanelTemplate>

  </ListBox.ItemsPanel>

  </ListBox>

  <Button Command="{Binding View}" Content="View" />

  </StackPanel>

  <ContentControl Content="{Binding}" Style="{StaticResource PaneStyle}" />

  </DockPanel>

  </Window>

  using CommunityToolkit.Mvvm.ComponentModel;

  using CommunityToolkit.Mvvm.Input;

  using System.Collections.ObjectModel;

  using System.Diagnostics;

  using System.Text.Json;

  using System.Text.Json.Serialization;

  using System.Windows;

  using System.Windows.Controls;

  using System.Windows.Media;

 

  namespace Questions355107

  {

  public class WindowModel : ObservableObject

  public double Top { get => top; set => SetProperty(ref top, value); }

  private double top = double.NaN;

  public double Left { get => left; set => SetProperty(ref left, value); }

  private double left = double.NaN;

  public double Width { get => width; set => SetProperty(ref width, value); }

  private double width = 800;

  public double Height { get => height; set => SetProperty(ref height, value); }

  private double height = 450;

 

  // 分割割合保存復元用 GridSplitter１本に対し文字列２つ

  // 大元（Settings）から変わるので、SetPropertyしなくてよかった模様

  // ついでに配列化してすっきり

  public class SplitterModel

  public string[] TwoPane { get; set; } = { "1*", "1*", };

  public string[] ThreePane { get; set; } = { "3*", "2*", "1*", "1*" };

  public string[] FourPane { get; set; } = { "1*", "1*", "1*", "1*", };

 

  public class SettingsModel

  public WindowModel Window { get; set; } = new();

  public SplitterModel Splitter { get; set; } = new();

 

  public class ContentModel

  public string Text { get; set; }

 

  // 実際に欲しい数値はここ

  // Viewから値が入るのみ コードから値を入れてもViewには反映しないので注意

  public double Width { get; set; }

  public double Height { get; set; }

  public Brush Brush { get; set; }

 

  public class ViewModel : ObservableObject

  public SettingsModel Settings { get => settings; set => SetProperty(ref settings, value); }

  private SettingsModel settings;

 

  public int[] Panes { get; } = { 1, 2, 3, 4, };

  public int SelPane { get => selPane; set => SetProperty(ref selPane, value); }

  private int selPane = 3;

  public ObservableCollection<ContentModel> Contents { get; }

 

  public RelayCommand Save { get; }

  public RelayCommand Load { get; }

  public RelayCommand View { get; }

 

  private string settingsJson;

  private readonly JsonSerializerOptions options = new()

  {

  NumberHandling = JsonNumberHandling.AllowNamedFloatingPointLiterals,

  WriteIndented = true,

  };

 

  public ViewModel()

  {

  Settings = new();

  Contents = new()

  new() { Text = "①", Brush = Brushes.LightCoral, },

  new() { Text = "②", Brush = Brushes.LightGreen, },

  new() { Text = "③", Brush = Brushes.SkyBlue, },

  new() { Text = "④", Brush = Brushes.Pink, },

  };

  Save = new(() =>

  settingsJson = JsonSerializer.Serialize(Settings, options);

  Debug.WriteLine(settingsJson);

  });

  Load = new(() =>

  Settings = null;

  Settings = JsonSerializer.Deserialize<SettingsModel>(settingsJson, options);

  });

  View = new(() =>

  foreach (var c in Contents)

  Debug.WriteLine($"{c.Text}: {c.Width:f2}, {c.Height:f2}");

  });

  Save.Execute(null);

  }

 

  public partial class MainWindow : Window

  public MainWindow() => InitializeComponent();

  private void Border_SizeChanged(object sender, SizeChangedEventArgs e)

  {

  if (sender is Border b && b.DataContext is ContentModel c)

  c.Width = b.ActualWidth;

  c.Height = b.ActualHeight;

  }

  }

  }

  <UserControl x:Class="Questions355107.TwoPane" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">

  <Grid>

  <Grid.ColumnDefinitions>

  <ColumnDefinition Width="{Binding Settings.Splitter.TwoPane[0], Mode=TwoWay}" />

  <ColumnDefinition Width="5" />

  <ColumnDefinition Width="{Binding Settings.Splitter.TwoPane[1], Mode=TwoWay}" />

  </Grid.ColumnDefinitions>

  <ContentControl Content="{Binding Contents[0]}" />

  <GridSplitter Grid.Column="1" />

  <ContentControl Grid.Column="2" Content="{Binding Contents[1]}" />

  </Grid>

  </UserControl>

  <UserControl x:Class="Questions355107.ThreePane" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">

  <Grid>

  <Grid.ColumnDefinitions>

  <ColumnDefinition Width="{Binding Settings.Splitter.ThreePane[0], Mode=TwoWay}" />

  <ColumnDefinition Width="5" />

  <ColumnDefinition Width="{Binding Settings.Splitter.ThreePane[1], Mode=TwoWay}" />

  </Grid.ColumnDefinitions>

  <ContentControl Content="{Binding Contents[0]}" />

  <GridSplitter Grid.Column="1" />

  <Grid Grid.Column="2">

  <Grid.RowDefinitions>

  <RowDefinition Height="{Binding Settings.Splitter.ThreePane[2], Mode=TwoWay}" />

  <RowDefinition Height="5" />

  <RowDefinition Height="{Binding Settings.Splitter.ThreePane[3], Mode=TwoWay}" />

  </Grid.RowDefinitions>

  <ContentControl Content="{Binding Contents[1]}" />

  <GridSplitter Grid.Row="1" />

  <ContentControl Grid.Row="2" Content="{Binding Contents[2]}" />

  </Grid>

  </Grid>

  </UserControl>

  <UserControl x:Class="Questions355107.FourPane" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">

  <Grid>

  <Grid.ColumnDefinitions>

  <ColumnDefinition Width="{Binding Settings.Splitter.FourPane[0], Mode=TwoWay}" />

  <ColumnDefinition Width="5" />

  <ColumnDefinition Width="{Binding Settings.Splitter.FourPane[1], Mode=TwoWay}" />

  </Grid.ColumnDefinitions>

  <Grid.RowDefinitions>

  <RowDefinition Height="{Binding Settings.Splitter.FourPane[2], Mode=TwoWay}" />

  <RowDefinition Height="5" />

  <RowDefinition Height="{Binding Settings.Splitter.FourPane[3], Mode=TwoWay}" />

  </Grid.RowDefinitions>

  <ContentControl Content="{Binding Contents[0]}" />

  <ContentControl Grid.Row="2" Content="{Binding Contents[1]}" />

  <ContentControl Grid.Column="2" Content="{Binding Contents[2]}" />

  <ContentControl Grid.Row="2" Grid.Column="2" Content="{Binding Contents[3]}" />

  <GridSplitter Grid.RowSpan="3" Grid.Column="1" />

  <GridSplitter Grid.Row="1" Grid.ColumnSpan="3" />

  </Grid>

  </UserControl>