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SelectedItem="{Binding Path=CurrentPageViewModel, Mode=TwoWay}"					

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<ItemsControl ItemsSource="{Binding Views}" DockPanel.Dock="Bottom">
    <ItemsControl.ItemTemplate>
        <DataTemplate >
            <Button Content="{Binding DisplayName}" Command="{Binding  DataContext.ChangeViewCommand , RelativeSource={RelativeSource AncestorType={x:Type Window}}}"  />
        </DataTemplate>                             
    </ItemsControl.ItemTemplate>                          
</ItemsControl>					

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public ICommand ChangePageCommand
    {
        get
        {
            if (_changePageCommand == null)
            {
                _changePageCommand = new RelayCommand(
                    p => ChangeViewModel((IPageViewModel)p),
                    p => p is IPageViewModel);
            }
 
            return _changePageCommand;
        }
    }					

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            ChangeViewRelay = new RelayCommand(p => ChangeViewModel((ViewModelBase)p), true);

       }					

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 public RelayCommand ChangeView
        {
            get;
            set;
        }					

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 private void ChangeViewModel(ViewModelBase viewModel)
        {
            if (!Views.Contains(viewModel))
            {
                Views.Add(viewModel);
            }
            CurrentPageView = Views.FirstOrDefault(vm => vm == viewModel);
        }