コマンド実行すると何かプロパティが変わったりするので、それをメイン側で表示するだけのような。
"コマンドの実行"自体を通知するなら、実行したというプロパティで通知するなど。
FrameのContentプロパティからPageが取れるので、そのDataContextをメイン側ViewにあるContentPresenterかContentControlのContentにバインドして、あとはDataTemplateでViewModelの型ごとに表示を切り替えてやるとか。
これならページ側はメイン側を全く知らなくてもいい。
あるいは面倒だけどFrameのContentをViewModel側にバインドで通知して、MainのViewModelではそのDataContextでコマンド実行されたことを検出する処理を入れてやるとか。
こっちはページ外部に伝える必要があることをページが知っていないといけない。
<Window x:Class="WpfApplication1.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:app="clr-namespace:WpfApplication1"
Title="MainWindow" Height="500" Width="305">
<Window.DataContext>
<app:MainViewVM />
</Window.DataContext>
<UniformGrid Rows="2">
<Frame x:Name="frame1" NavigationUIVisibility="Visible" Source="{Binding Path=Source,Mode=TwoWay}">
<Frame.CommandBindings>
<CommandBinding Command="{x:Static NavigationCommands.GoToPage}"
Executed="CommandBinding_Executed"/>
</Frame.CommandBindings>
<Frame.Content>
<Binding Path="DataContext" Mode="OneWayToSource">
<Binding.Converter>
<app:DataContextConverter />
</Binding.Converter>
</Binding>
</Frame.Content>
</Frame>
<StackPanel Background="Black" TextElement.Foreground="White">
<GroupBox Header="ViewModel経由でごちゃごちゃと" Margin="10">
<StackPanel>
<TextBlock Text="{Binding Path=Source}" Margin="5"/>
<TextBlock Text="{Binding Path=DataContext}" Margin="5"/>
<TextBlock Text="{Binding Path=Message}" Margin="5"/>
</StackPanel>
</GroupBox>
<GroupBox Header="View層で切り替え" BorderBrush="LightGray" Margin="10"
DataContext="{Binding Path=Content.DataContext,ElementName=frame1}">
<StackPanel >
<ItemsControl ItemsSource="{Binding Path=Commands}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Button Command="{Binding Value}" Content="{Binding Path=Key}" Margin="2"/>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
<ContentPresenter Content="{Binding Path=.}">
<ContentPresenter.Resources>
<DataTemplate DataType="{x:Type app:Page1VM}" >
<StackPanel>
<Slider Minimum="0" Maximum="10000" TickFrequency="1" Value="{Binding Path=Value}"/>
<TextBlock Text="{Binding Path=Message}" />
</StackPanel>
</DataTemplate>
<DataTemplate DataType="{x:Type app:Page2VM}" >
<StackPanel>
<TextBlock Text="{Binding Path=Now,StringFormat=HH:mm:ss}" />
</StackPanel>
</DataTemplate>
</ContentPresenter.Resources>
</ContentPresenter>
</StackPanel>
</GroupBox>
</StackPanel>
</UniformGrid>
</Window>
<Page x:Class="WpfApplication1.Page1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:app="clr-namespace:WpfApplication1"
Title="Page1">
<Page.DataContext>
<app:Page1VM />
</Page.DataContext>
<StackPanel>
<Button Command="{x:Static NavigationCommands.BrowseBack}" Content="＜"/>
<TextBlock><Hyperlink NavigateUri="Page2.xaml">Page2</Hyperlink></TextBlock>
<TextBlock Text="{Binding Path=Value}" Margin="20"/>
<Button Command="{Binding Path=TestCommand}" Content="x10"/>
</StackPanel>
</Page>
<Page x:Class="WpfApplication1.Page2" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:app="clr-namespace:WpfApplication1"
Title="Page2">
<Page.DataContext>
<app:Page2VM />
</Page.DataContext>
<StackPanel>
<Button Command="{x:Static NavigationCommands.BrowseBack}" Content="＜"/>
<Button Command="{x:Static NavigationCommands.GoToPage}" CommandParameter="Page3.xaml" Content="Page3"/>
<TextBlock Text="{Binding Path=Now}" Margin="50" Language="ja-jp"/>
</StackPanel>
</Page>
<Page x:Class="WpfApplication1.Page3" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:app="clr-namespace:WpfApplication1"
Title="Page3">
<Page.DataContext>
<app:Page3VM />
</Page.DataContext>
<StackPanel>
<Button Command="{x:Static NavigationCommands.BrowseBack}" Content="＜"/>
<Button Command="{Binding Path=TestCommand}" Content="Test" />
</StackPanel>
</Page>
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Input;
using System.ComponentModel;
using System.Collections.Generic;
using System.Collections.ObjectModel;
namespace WpfApplication1
{
public partial class MainWindow : Window
{
public MainWindow() { InitializeComponent(); }
private void CommandBinding_Executed(object sender, ExecutedRoutedEventArgs e)
{
((Frame)sender).Navigate(e.Parameter as Uri ?? new Uri(e.Parameter.ToString(), UriKind.Relative));
}
}
class ModelBase : INotifyPropertyChanged, ICommandExecuted
{
public ModelBase ()
{
Commands = new Dictionary<string, ICommand>();
}
public event System.ComponentModel.PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged(string name)
{
var pc = PropertyChanged;
if (pc != null) { pc(this, new System.ComponentModel.PropertyChangedEventArgs(name)); }
}
public event EventHandler<CommandExecutedEventArgs> CommandExecuted;
protected void OnCommandExecuted(string commandName)
{
var ce = CommandExecuted;
if (ce != null) { ce(this, new CommandExecutedEventArgs(commandName)); }
}
public Dictionary<string,ICommand> Commands{get;private set;}
}
class MainViewVM : ModelBase
{
/// <summary>Frameに表示されている(させたい)ページのUri</summary>
public Uri Source
{
get { return _Source; }
set { if (_Source != value) { _Source = value; OnPropertyChanged("Source"); } }
}
private Uri _Source = new Uri("Page1.xaml", UriKind.Relative);
/// <summary>Converter経由でFrameに表示されているページのDataContextを受け取る</summary>
public object DataContext
{
get { return _DataContext; }
set
{
if (_DataContext != value)
{
var npc = _DataContext as INotifyPropertyChanged;
if (npc != null) { npc.PropertyChanged -= OnFrameDataContextChanged; }
var ce = _DataContext as ICommandExecuted;
if (ce != null) { ce.CommandExecuted -= OnFrameCommandExecuted; }
_DataContext = value;
npc = _DataContext as INotifyPropertyChanged;
if (npc != null) { npc.PropertyChanged += OnFrameDataContextChanged; }
ce = _DataContext as ICommandExecuted;
if (ce != null) { ce.CommandExecuted += OnFrameCommandExecuted; }
Message = "";
OnPropertyChanged("DataContext");
}
}
}
private object _DataContext;
/// <summary>
/// FrameのDataContextが何か変化したら呼ばれる
/// コマンドを実行すれば何かプロパティが変化するならこっちだけで済む
/// </summary>
private void OnFrameDataContextChanged(object sender, PropertyChangedEventArgs e)
{
var value = sender.GetType().GetProperty(e.PropertyName).GetValue(sender, null);
Message = string.Format("{0}:{1}={2}", sender, e.PropertyName, value);
}
/// <summary>コマンドを実行したけど何もプロパティが変化しない場合でも"実行した"ことを知りたい場合</summary>
void OnFrameCommandExecuted(object sender, CommandExecutedEventArgs e)
{
Message = string.Format("{0}:{1} Executed!", sender, e.CommandName);
}
public string Message
{
get { return _Message; }
set { if (_Message != value) { _Message = value; OnPropertyChanged("Message"); } }
}
private string _Message;
}
class Page1VM : ModelBase
{
public Page1VM()
{
TestCommand = new DelegateCommand((o) => { Value *= 10; Message = "Valueを10倍にしました"; });
base.Commands.Add("x10", TestCommand);
base.Commands.Add("/10",new DelegateCommand((o) => { Value /= 10; Message = "Valueを1/10倍にしました"; }));
}
public int Value
{
get { return _Value; }
set { if (_Value != value) { _Value = value; OnPropertyChanged("Value"); } }
}
private int _Value=10;
public ICommand TestCommand { get; private set; }
public string Message
{
get { return _Message; }
set { if (_Message != value) { _Message = value; OnPropertyChanged("Message"); } }
}
private string _Message;
}
class Page2VM : ModelBase
{
private System.Windows.Threading.DispatcherTimer timer;
public Page2VM()
{
timer = new System.Windows.Threading.DispatcherTimer();
timer.Interval = TimeSpan.FromSeconds(1);
timer.Tick += (s, e) => { OnPropertyChanged("Now"); };
timer.Start();
}
public DateTime Now { get { return DateTime.Now; } }
}
class Page3VM : ModelBase
{
public Page3VM()
{
TestCommand = new DelegateCommand((o) =>{ OnCommandExecuted("TestCommand"); });
base.Commands.Add("Test",TestCommand);
}
public ICommand TestCommand { get; private set; }
}
/// <summary>FrameworkElementに設定されているDataContextをソース側に伝えるコンバーター</summary>
/// <author></author>
/// <remarks></remarks>
/// <date>2015/11/29</date>
[ValueConversion(typeof(FrameworkElement), typeof(object))]
class DataContextConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
return value;
}
public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
if (value is FrameworkElement)
{
return ((FrameworkElement)value).DataContext;
}
return null;
}
}
#region コマンドを"実行した"ことをViewModel層で伝えるためのインターフェース</summary>
public interface ICommandExecuted
{
event EventHandler<CommandExecutedEventArgs> CommandExecuted;
}
public class CommandExecutedEventArgs : EventArgs
{
public CommandExecutedEventArgs(string commandName) { this.CommandName = commandName; }
public string CommandName { get; private set; }
}
public class DelegateCommand : ICommand
{
public DelegateCommand(Action<object> a)
{
this._Action = a;
}
private Action<object> _Action;
public event EventHandler CanExecuteChanged;
public bool CanExecute(object parameter)
{
return true;
}
public void Execute(object parameter) { _Action(parameter); }
}
#endregion
}
個別に明示されていない限りgekkaがフォーラムに投稿したコードにはフォーラム使用条件に基づき「MICROSOFT LIMITED PUBLIC LICENSE」が適用されます。(かなり自由に使ってOK!)
